1
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Pizzochero M, Tepliakov NV, Lischner J, Mostofi AA, Kaxiras E. One-Dimensional Magnetic Conduction Channels across Zigzag Graphene Nanoribbon/Hexagonal Boron Nitride Heterojunctions. NANO LETTERS 2024. [PMID: 38788172 DOI: 10.1021/acs.nanolett.4c00920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
We examine the electronic structure of recently fabricated in-plane heterojunctions of zigzag graphene nanoribbons embedded in hexagonal boron nitride. We focus on hitherto unexplored interface configurations in which both edges of the nanoribbon are bonded to the same chemical species, either boron or nitrogen atoms. Using ab initio and mean-field Hubbard model calculations, we reveal the emergence of one-dimensional magnetic conducting channels at these interfaces. These channels originate from the energy shift of the magnetic interface states that is induced by charge transfer between the nanoribbon and hexagonal boron nitride. We further address the response of these heterojunctions to external electric and magnetic fields, demonstrating the tunability of energy and spin splittings in the electronic structure. Our findings establish that zigzag graphene nanoribbon/hexagonal boron nitride heterojunctions are a suitable platform for exploring and engineering spin transport in the atomically thin limit, with potential applications in integrated spintronic devices.
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Affiliation(s)
- Michele Pizzochero
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Nikita V Tepliakov
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Johannes Lischner
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Arash A Mostofi
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Efthimios Kaxiras
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
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2
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Logrado AL, Cassiano TDSA, da Cunha WF, Gargano R, E Silva GM, de Oliveira Neto PH. Width effects on bilayer graphene nanoribbon polarons. Phys Chem Chem Phys 2024; 26:14948-14959. [PMID: 38739011 DOI: 10.1039/d4cp00760c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Recent progress in nanoelectronics suggests that stacking armchair graphene nanoribbons (AGNRs) into bilayer systems can generate materials with emergent quasiparticle properties. In this context, the impact of width changes is especially relevant. However, its effect on charged carriers remains elusive. In this work, we investigate the effect of width and interlayer interaction changes on polaron states via a hybrid Hamiltonian that couples the electronic and lattice interactions. Results show the rising of two interlayer polarons: the non-symmetric and the symmetric. The coupling strength needed to induce the transition between states depends on the nanoribbon width, being at the most extreme case of ≈174 meV. Electronic properties such as the coupling strength threshold, carrier size, and gap are shown to respect the AGNR width family 3p, 3p + 1, and 3p + 2 rule. The findings demonstrate that strong interlayer interaction simultaneously delocalizes the carriers and reduces the gap up to 0.6 eV. Additionally, it is found that some layers are more prone to share charge, indicating a potential heterogeneous stacking where a particular electronic pathway is favored. The results present an encouraging prospect for integrating AGNR bilayers in future flexible electronics.
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Affiliation(s)
- André Lima Logrado
- Institute of Physics, University of Brasília, 70919-970, Brasília, Brazil.
| | | | | | - Ricardo Gargano
- Institute of Physics, University of Brasília, 70919-970, Brasília, Brazil.
| | | | - Pedro Henrique de Oliveira Neto
- Institute of Physics, University of Brasília, 70919-970, Brasília, Brazil.
- International Center of Physics, University of Brasília, 70919-970, Brazil
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3
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Šćepanović S, Kimouche A, Mirković J, Sadiek G, Klamroth T, Hassanien A. Delocalized spin states at zigzag termini of armchair graphene nanoribbon. Sci Rep 2024; 14:11641. [PMID: 38773311 PMCID: PMC11109170 DOI: 10.1038/s41598-024-62624-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/20/2024] [Indexed: 05/23/2024] Open
Abstract
Using scanning tunneling microscopy and spectroscopy we demonstrate a revival of magnetism in 7-armchair nanoribbon by unpassivated atoms at the termini. Namely, a pair of intense Kondo resonances emerges at the peripheries of zigzag terminus revealing the many-body screening effects of local magnetic moments. Although Kondo resonance originates from a missing local orbital, it extends to a distance of 2.5 nm along the edge of the ribbon. The results are complemented by density functional theory calculations which suggest a possible coupling between Kondo states despite screening effects of substrate electrons. These findings indicate a possibility to restore intrinsic magnetic ordering in graphene nanoribbon without major structural modifications.
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Affiliation(s)
- Stefan Šćepanović
- Jozef Stefan Institute, 39 Jamova, 1000, Ljubljana, Slovenia
- Faculty of Sciences, University of Montenegro, 81000, Podgorica, Montenegro
| | - Amina Kimouche
- Institute of Physics and Astronomy, University of Potsdam, 14476, Potsdam, Germany
| | - Jovan Mirković
- Faculty of Sciences, University of Montenegro, 81000, Podgorica, Montenegro
| | - Gehad Sadiek
- Department of Applied Physics and Astronomy, University of Sharjah, 27272, Sharjah, UAE
| | - Tillmann Klamroth
- Institute of Chemistry, University of Potsdam, 14476, Potsdam, Germany
| | - Abdou Hassanien
- Jozef Stefan Institute, 39 Jamova, 1000, Ljubljana, Slovenia.
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4
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Dong W, Li X, Lu S, Li J, Wang Y, Zhong M, Dong X, Xu Z, Shen Q, Gao S, Wu K, Peng LM, Hou S, Zhang Z, Zhang Y, Wang Y. Unzipping Carbon Nanotubes to Sub-5-nm Graphene Nanoribbons on Cu(111) by Surface Catalysis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2308430. [PMID: 38126626 DOI: 10.1002/smll.202308430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/23/2023] [Indexed: 12/23/2023]
Abstract
Graphene nanoribbons (GNRs) are promising in nanoelectronics for their quasi-1D structures with tunable bandgaps. The methods for controllable fabrication of high-quality GNRs are still limited. Here a way to generate sub-5-nm GNRs by annealing single-walled carbon nanotubes (SWCNTs) on Cu(111) is demonstrated. The structural evolution process is characterized by low-temperature scanning tunneling microscopy. Substrate-dependent measurements on Au(111) and Ru(0001) reveal that the intermediate strong SWCNT-surface interaction plays a pivotal role in the formation of GNRs.
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Affiliation(s)
- Wenjie Dong
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Xin Li
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Shuai Lu
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Jie Li
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yansong Wang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Mingjun Zhong
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Xu Dong
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Zhen Xu
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Qian Shen
- Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Nanjing Tech University, Nanjing, 211816, China
| | - Song Gao
- Institute of Spin Science and Technology, South China University of Technology, Guangzhou, 511442, China
| | - Kai Wu
- BNLMS, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Lian-Mao Peng
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Shimin Hou
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Zhiyong Zhang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yajie Zhang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
| | - Yongfeng Wang
- Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing, 100871, China
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5
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Slicker K, Delgado A, Jiang J, Tang W, Cronin A, Blackwell RE, Louie SG, Fischer FR. Engineering Small HOMO-LUMO Gaps in Polycyclic Aromatic Hydrocarbons with Topologically Protected States. NANO LETTERS 2024; 24:5387-5392. [PMID: 38629638 PMCID: PMC11066967 DOI: 10.1021/acs.nanolett.4c01476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 05/02/2024]
Abstract
Topological phases in laterally confined low-dimensional nanographenes have emerged as versatile design tools that can imbue otherwise unremarkable materials with exotic band structures ranging from topological semiconductors and quantum dots to intrinsically metallic bands. The periodic boundary conditions that define the topology of a given lattice have thus far prevented the translation of this technology to the quasi-zero-dimensional (0D) domain of small molecular structures. Here, we describe the synthesis of a polycyclic aromatic hydrocarbon (PAH) featuring two localized zero modes (ZMs) formed by the topological junction interface between a trivial and nontrivial phase within a single molecule. First-principles density functional theory calculations predict a strong hybridization between adjacent ZMs that gives rise to an exceptionally small HOMO-LUMO gap. Scanning tunneling microscopy and spectroscopy corroborate the molecular structure of 9/7/9-double quantum dots and reveal an experimental quasiparticle gap of 0.16 eV, corresponding to a carbon-based small molecule long-wavelength infrared (LWIR) absorber.
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Affiliation(s)
- Kaitlin Slicker
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Aidan Delgado
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Jingwei Jiang
- Department
of Physics, University of California, Berkeley, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Weichen Tang
- Department
of Physics, University of California, Berkeley, Berkeley, California 94720, United States
| | - Adam Cronin
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Raymond E. Blackwell
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Steven G. Louie
- Department
of Physics, University of California, Berkeley, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Felix R. Fischer
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley,
and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bakar
Institute of Digital Materials for the Planet, Division of Computing,
Data Science, and Society, University of
California, Berkeley, Berkeley, California 94720, United States
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6
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Louis E, Chiappe G, Vergés JA, San-Fabián E. Long-Range Effects in Topologically Defective Arm-Chair Graphene Nanoribbons. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:778. [PMID: 38727373 PMCID: PMC11085075 DOI: 10.3390/nano14090778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/26/2024] [Accepted: 04/27/2024] [Indexed: 05/13/2024]
Abstract
The electronic structure of 7/9-AGNR superlattices with up to eight unit cells has been studied by means of state-of-the-art Density Functional Theory (DFT) and also by two model Hamiltonians, the first one including only local interactions (Hubbard model, Hu) while the second one is extended to allow long-range Coulomb interactions (Pariser, Parr and Pople model, PPP). Both are solved within mean field approximation. At this approximation level, our calculations show that 7/9 interfaces are better described by spin non-polarized solutions than by spin-polarized wavefunctions. Consequently, both Hu and PPP Hamiltonians lead to electronic structures characterized by a gap at the Fermi level that diminishes as the size of the system increases. DFT results show similar trends although a detailed analysis of the density of states around the Fermi level shows quantitative differences with both Hu and PPP models. Before improving model Hamiltonians, we interpret the electronic structure obtained by DFT in terms of bands of topological states: topological states localized at the system edges and extended bulk topological states that interact between them due to the long-range Coulomb terms of Hamiltonian. After careful analysis of the interaction among topological states, we find that the discrepancy between ab initio and model Hamiltonians can be resolved considering a screened long-range interaction that is implemented by adding an exponential cutoff to the interaction term of the PPP model. In this way, an adjusted cutoff distance λ=2 allows a good recovery of DFT results. In view of this, we conclude that the correct description of the density of states around the Fermi level (Dirac point) needs the inclusion of long-range interactions well beyond the Hubbard model but not completely unscreened as is the case for the PPP model.
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Affiliation(s)
- Enrique Louis
- Departamento de Física Aplicada, Instituto Universitario de Materiales de Alicante (IUMA), Universidad de Alicante, 03080 Alicante, Spain;
| | - Guillermo Chiappe
- Departamento de Física Aplicada, Instituto Universitario de Materiales de Alicante (IUMA), Universidad de Alicante, 03080 Alicante, Spain;
| | - José A. Vergés
- Departamento de Teoría y Simulación de Materiales, Instituto de Ciencia de Materiales de Madrid (CSIC), Cantoblanco, 28049 Madrid, Spain;
| | - Emilio San-Fabián
- Departamento de Química Física, Instituto Universitario de Materiales de Alicante (IUMA), Universidad de Alicante, 03080 Alicante, Spain
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7
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Palumbo G. Topological phase transitions with zero indirect band gaps. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:26LT01. [PMID: 38572591 DOI: 10.1088/1361-648x/ad3872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 03/27/2024] [Indexed: 04/05/2024]
Abstract
Topological phase transitions in band models are usually associated to the gap closing between the highest valance band and the lowest conduction band, which can give rise to different types of nodal structures, such as Dirac/Weyl points, lines and surfaces. In this work, we show the existence of a different kind of topological phase transitions in one-dimensional systems, which are instead characterized by the presence of a robust zero indirect gap, which occurs when the top of the valence band coincides with the bottom of the conduction band in energy but not in momentum. More specifically, we consider an one-dimensional model on a trimer chain that is protected by both particle-hole and chiral-inversion symmetries. At the critical point, the system supports a Dirac-like point. After introducing a deforming parameter that breaks both inversion and chiral symmetries but preserves their combination, we observe the emergence of a zero indirect band gap, which results to be related to thepersymmetryof our Hamiltonian. Importantly, the zero indirect gap holds for a range of values of the deforming parameter. We finally discuss the implementation of the deforming parameter in our tight-binding model through time-periodic (Floquet) driving.
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Affiliation(s)
- Giandomenico Palumbo
- School of Theoretical Physics, Dublin Institute for Advanced Studies, 10 Burlington Road, Dublin 4, Ireland
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8
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Zhu X, Li K, Liu J, Wang Z, Ding Z, Su Y, Yang B, Yan K, Li G, Yu P. Topological Structure Realized in Cove-Edged Graphene Nanoribbons via Incorporation of Periodic Pentagon Rings. J Am Chem Soc 2024; 146:7152-7158. [PMID: 38421279 DOI: 10.1021/jacs.4c00270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Cove-edged zigzag graphene nanoribbons are predicted to show metallic, topological, or trivial semiconducting band structures, which are precisely determined by their cove offset positions at both edges as well as the ribbon width. However, due to the challenge of introducing coves into zigzag-edged graphene nanoribbons, only a few cove-edged graphene nanoribbons with trivial semiconducting bandgaps have been realized experimentally. Here, we report that the topological band structure can be realized in cove-edged graphene nanoribbons by embedding periodic pentagon rings on the cove edges through on-surface synthesis. Upon noncontact atomic force microscopy and scanning tunneling spectroscopy measurements, the chemical and electronic structures of cove-edged graphene nanoribbons with periodic pentagon rings have been characterized for different lengths. Combined with theoretical calculations, we find that upon inducing periodic pentagon rings the cove-edged graphene nanoribbons exhibit nontrivial topological structures. Our results provide insights for the design and understanding of the topological character in cove-edged graphene nanoribbons.
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Affiliation(s)
- Xujie Zhu
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Kezhen Li
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Jian Liu
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Zhou Wang
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Zhihao Ding
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Yunlong Su
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Bo Yang
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - KaKing Yan
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Gang Li
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, 201210 Shanghai, China
| | - Ping Yu
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
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9
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Fang T, Zhang T, Hu T, Wang Z. Atomic-Limit Mott Insulator in [4]Triangulene Frameworks. NANO LETTERS 2024; 24:3059-3066. [PMID: 38426713 DOI: 10.1021/acs.nanolett.3c04675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Triangulene, one unique class of zigzag-edged triangular graphene molecules, has attracted tremendous research interest. In this work, as an ultimate phase of the Mott insulator, we present the realization of the atomic-limit Mott insulator in experimentally synthesized [4]triangulene frameworks ([4]-TGFs) from first-principles calculations. The frontier molecular orbitals of the nonmagnetic [4]triangulene consist of three coupled corner modes. After the isolated [4]triangulene is assembled into [4]-TGF, one special enantiomorphic flat band is created through the coupling of these corner modes, which is identified to be a second-order topological insulator with half-filled topological corner states at the Fermi level. Moreover, [4]-TGF prefers an antiferromagnetic ground state under Hubbard interactions, which further splits these metallic zero-energy states into an atomic-limit Mott insulator with spin-polarized corners. Since the fractional filling of topological corner states is a smoking-gun signature of higher-order topology, our results demonstrate a universal approach to explore the atomic-limit Mott insulators in higher-order topological materials.
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Affiliation(s)
- Tiancheng Fang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Tingfeng Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Tianyi Hu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Zhengfei Wang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, People's Republic of China
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10
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Jacobse PH, Sarker M, Saxena A, Zahl P, Wang Z, Berger E, Aluru NR, Sinitskii A, Crommie MF. Tunable Magnetic Coupling in Graphene Nanoribbon Quantum Dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2400473. [PMID: 38412424 DOI: 10.1002/smll.202400473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Indexed: 02/29/2024]
Abstract
Carbon-based quantum dots (QDs) enable flexible manipulation of electronic behavior at the nanoscale, but controlling their magnetic properties requires atomically precise structural control. While magnetism is observed in organic molecules and graphene nanoribbons (GNRs), GNR precursors enabling bottom-up fabrication of QDs with various spin ground states have not yet been reported. Here the development of a new GNR precursor that results in magnetic QD structures embedded in semiconducting GNRs is reported. Inserting one such molecule into the GNR backbone and graphitizing it results in a QD region hosting one unpaired electron. QDs composed of two precursor molecules exhibit nonmagnetic, antiferromagnetic, or antiferromagnetic ground states, depending on the structural details that determine the coupling behavior of the spins originating from each molecule. The synthesis of these QDs and the emergence of localized states are demonstrated through high-resolution atomic force microscopy (HR-AFM), scanning tunneling microscopy (STM) imaging, and spectroscopy, and the relationship between QD atomic structure and magnetic properties is uncovered. GNR QDs provide a useful platform for controlling the spin-degree of freedom in carbon-based nanostructures.
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Affiliation(s)
- Peter H Jacobse
- Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Mamun Sarker
- Department of Chemistry, University of Nebraska, Lincoln, NE, 68588, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Anshul Saxena
- Walker Department of Mechanical Engineering, University of Texas, Austin, TX, 78712, USA
- Oden Institute for Computational Engineering and Sciences, University of Texas at Austin, Austin, TX, 78712, USA
| | - Percy Zahl
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Ziyi Wang
- Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Kavli Energy NanoSciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Emma Berger
- Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Narayana R Aluru
- Walker Department of Mechanical Engineering, University of Texas, Austin, TX, 78712, USA
- Oden Institute for Computational Engineering and Sciences, University of Texas at Austin, Austin, TX, 78712, USA
| | - Alexander Sinitskii
- Department of Chemistry, University of Nebraska, Lincoln, NE, 68588, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Michael F Crommie
- Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Kavli Energy NanoSciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
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11
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Alcón I, Cummings AW, Roche S. Tailoring giant quantum transport anisotropy in nanoporous graphenes under electrostatic disorder. NANOSCALE HORIZONS 2024; 9:407-415. [PMID: 38275013 DOI: 10.1039/d3nh00416c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
During the last 15 years bottom-up on-surface synthesis has been demonstrated as an efficient way to synthesize carbon nanostructures with atomic precision, opening the door to unprecedented electronic control at the nanoscale. Nanoporous graphenes (NPGs) fabricated as two-dimensional arrays of graphene nanoribbons (GNRs) represent one of the key recent breakthroughs in the field. NPGs interestingly display in-plane transport anisotropy of charge carriers, and such anisotropy was shown to be tunable by modulating quantum interference. Herein, using large-scale quantum transport simulations, we show that electrical anisotropy in NPGs is not only resilient to disorder but can further be massively enhanced by its presence. This outcome paves the way to systematic engineering of quantum transport in NPGs as a novel concept for efficient quantum devices and architectures.
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Affiliation(s)
- Isaac Alcón
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Aron W Cummings
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
| | - Stephan Roche
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
- ICREA, Institució Catalana de Recerca i Estudis Avançats, 08070 Barcelona, Spain
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12
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Jiang YC, Kariyado T, Hu X. Topological electronic states in holey graphyne. NANOTECHNOLOGY 2024; 35:195201. [PMID: 38295413 DOI: 10.1088/1361-6528/ad2483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 01/31/2024] [Indexed: 02/02/2024]
Abstract
We unveil that the holey graphyne (HGY), a two-dimensional carbon allotrope where benzene rings are connected by two -C≡C- bonds fabricated recently in a bottom-up way, exhibits topological electronic states. Using first-principles calculations and Wannier tight-binding modeling, we discover a higher-order topological invariant associated withC2symmetry of the material, and show that the resultant corner modes appear in nanoflakes matching to the structure of precursor reported previously, which are ready for direct experimental observations. In addition, we find that a band inversion between emergentg-like andh-like orbitals gives rise to a nontrivial topology characterized byZ2invariant protected by an energy gap as large as 0.52 eV, manifesting helical edge states mimicking those in the prominent quantum spin Hall effect, which can be accessed experimentally after hydrogenation in HGY. We hope these findings trigger interests towards exploring the topological electronic states in HGY and related future electronics applications.
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Affiliation(s)
- Yong-Cheng Jiang
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan
- Graduate School of Science and Technology, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Toshikaze Kariyado
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan
| | - Xiao Hu
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan
- Graduate School of Science and Technology, University of Tsukuba, Tsukuba 305-8571, Japan
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13
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Piquero-Zulaica I, Corral-Rascón E, Diaz de Cerio X, Riss A, Yang B, Garcia-Lekue A, Kher-Elden MA, Abd El-Fattah ZM, Nobusue S, Kojima T, Seufert K, Sakaguchi H, Auwärter W, Barth JV. Deceptive orbital confinement at edges and pores of carbon-based 1D and 2D nanoarchitectures. Nat Commun 2024; 15:1062. [PMID: 38316774 PMCID: PMC10844643 DOI: 10.1038/s41467-024-45138-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 01/15/2024] [Indexed: 02/07/2024] Open
Abstract
The electronic structure defines the properties of graphene-based nanomaterials. Scanning tunneling microscopy/spectroscopy (STM/STS) experiments on graphene nanoribbons (GNRs), nanographenes, and nanoporous graphene (NPG) often determine an apparent electronic orbital confinement into the edges and nanopores, leading to dubious interpretations such as image potential states or super-atom molecular orbitals. We show that these measurements are subject to a wave function decay into the vacuum that masks the undisturbed electronic orbital shape. We use Au(111)-supported semiconducting gulf-type GNRs and NPGs as model systems fostering frontier orbitals that appear confined along the edges and nanopores in STS measurements. DFT calculations confirm that these states originate from valence and conduction bands. The deceptive electronic orbital confinement observed is caused by a loss of Fourier components, corresponding to states of high momentum. This effect can be generalized to other 1D and 2D carbon-based nanoarchitectures and is important for their use in catalysis and sensing applications.
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Affiliation(s)
- Ignacio Piquero-Zulaica
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany.
| | - Eduardo Corral-Rascón
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany
| | - Xabier Diaz de Cerio
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018, Donostia-San Sebastian, Spain
| | - Alexander Riss
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany.
| | - Biao Yang
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany
| | - Aran Garcia-Lekue
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018, Donostia-San Sebastian, Spain.
- Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain.
| | - Mohammad A Kher-Elden
- Physics Department, Faculty of Science, Al-Azhar University, Nasr City, E-11884, Cairo, Egypt
| | - Zakaria M Abd El-Fattah
- Physics Department, Faculty of Science, Al-Azhar University, Nasr City, E-11884, Cairo, Egypt
| | - Shunpei Nobusue
- Institute of Advanced Energy, Kyoto University, Uji, 611-0011, Kyoto, Japan
| | - Takahiro Kojima
- Institute of Advanced Energy, Kyoto University, Uji, 611-0011, Kyoto, Japan
| | - Knud Seufert
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany
| | - Hiroshi Sakaguchi
- Institute of Advanced Energy, Kyoto University, Uji, 611-0011, Kyoto, Japan.
| | - Willi Auwärter
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany
| | - Johannes V Barth
- Physics Department E20, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, D-85748, Garching, Germany
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14
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Zhong Q, Jung J, Kohrs D, Kaczmarek LA, Ebeling D, Mollenhauer D, Wegner HA, Schirmeisen A. Deciphering the Mechanism of On-Surface Dehydrogenative C-C Coupling Reactions. J Am Chem Soc 2024; 146:1849-1859. [PMID: 38226612 DOI: 10.1021/jacs.3c05233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
On-surface synthesis has proven to be a powerful approach for fabricating various low-dimensional covalent nanostructures with atomic precision that could be challenging for conventional solution chemistry. Dehydrogenative Caryl-Caryl coupling is one of the most popular on-surface reactions, of which the mechanisms, however, have not been well understood due to the lack of microscopic insights into the intermediates that are fleetingly existing under harsh reaction conditions. Here, we bypass the most energy-demanding initiation step to generate and capture some of the intermediates at room temperature (RT) via the cyclodehydrobromination of 1-bromo-8-phenylnaphthalene on a Cu(111) surface. Bond-level scanning probe imaging and manipulation in combination with DFT calculations allow for the identification of chemisorbed radicals, cyclized intermediates, and dehydrogenated products. These intermediates correspond to three main reaction steps, namely, debromination, cyclization (radical addition), and H elimination. H elimination is the rate-determining step as evidenced by the predominant cyclized intermediates. Furthermore, we reveal a long-overlooked pathway of dehydrogenation, namely, atomic hydrogen-catalyzed H shift and elimination, based on the observation of intermediates for H shift and superhydrogenation and the proof of a self-amplifying effect of the reaction. This pathway is further corroborated by comprehensive theoretical analysis on the reaction thermodynamics and kinetics.
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Affiliation(s)
- Qigang Zhong
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen 35392, Germany
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Functional Nano & Soft Materials, Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, P. R. China
| | - Jannis Jung
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Physical Chemistry, Justus Liebig University Giessen, Giessen 35392, Germany
| | - Daniel Kohrs
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen 35392, Germany
| | - L Alix Kaczmarek
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Physical Chemistry, Justus Liebig University Giessen, Giessen 35392, Germany
| | - Daniel Ebeling
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen 35392, Germany
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
| | - Doreen Mollenhauer
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Physical Chemistry, Justus Liebig University Giessen, Giessen 35392, Germany
| | - Hermann A Wegner
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
- Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen 35392, Germany
| | - André Schirmeisen
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen 35392, Germany
- Center for Materials Research (LaMa), Justus Liebig University Giessen, Giessen 35392, Germany
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15
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Li Q, Wang L, Li H, Chan MKY, Hersam MC. Synthesis of Quantum-Confined Borophene Nanoribbons. ACS NANO 2024; 18:483-491. [PMID: 37939213 DOI: 10.1021/acsnano.3c08089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Borophene nanoribbons (BNRs) are one-dimensional strips of atomically thin boron expected to exhibit quantum-confined electronic properties that are not present in extended two-dimensional borophene. While the parent material borophene has been experimentally shown to possess anisotropic metallicity and diverse polymorphic structures, the atomically precise synthesis of nanometer-wide BNRs has not yet been achieved. Here, we demonstrate the synthesis of multiple BNR polymorphs with well-defined edge configurations within the nanometer-scale terraces of vicinal Ag(977). Through atomic-scale imaging, spectroscopy, and first-principles calculations, the synthesized BNR polymorphs are characterized and found to possess distinct edge structures and electronic properties. For single-phase BNRs, v1/6-BNRs and v1/5-BNRs adopt reconstructed armchair edges and sawtooth edges, respectively. In addition, the electronic properties of single-phase v1/6-BNRs and v1/5-BNRs are dominated by Friedel oscillations and striped moiré patterns, respectively. On the other hand, mixed-phase BNRs possess quantum-confined states with increasing nodes in the electronic density of states at elevated biases. Overall, the high degree of polymorphism and diverse edge topologies in borophene nanoribbons provide a rich quantum platform for studying one-dimensional electronic states.
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Affiliation(s)
- Qiucheng Li
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
| | - Luqing Wang
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
- Northwestern-Argonne Institute of Science and Engineering, 2205 Tech Drive, Evanston, Illinois 60208, United States
| | - Hui Li
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
| | - Maria K Y Chan
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
- Northwestern-Argonne Institute of Science and Engineering, 2205 Tech Drive, Evanston, Illinois 60208, United States
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Department of Electrical and Computer Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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16
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Jacobse P, Daugherty MC, Čerņevičs K, Wang Z, McCurdy RD, Yazyev OV, Fischer FR, Crommie MF. Five-Membered Rings Create Off-Zero Modes in Nanographene. ACS NANO 2023; 17:24901-24909. [PMID: 38051766 PMCID: PMC10753889 DOI: 10.1021/acsnano.3c06006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 11/18/2023] [Accepted: 12/01/2023] [Indexed: 12/07/2023]
Abstract
The low-energy electronic structure of nanographenes can be tuned through zero-energy π-electron states, typically referred to as zero-modes. Customizable electronic and magnetic structures have been engineered by coupling zero-modes through exchange and hybridization interactions. Manipulation of the energy of such states, however, has not yet received significant attention. We find that attaching a five-membered ring to a zigzag edge hosting a zero-mode perturbs the energy of that mode and turns it into an off-zero mode: a localized state with a distinctive electron-accepting character. Whereas the end states of typical 7-atom-wide armchair graphene nanoribbons (7-AGNRs) lose their electrons when physisorbed on Au(111) (due to its high work function), converting them into off-zero modes by introducing cyclopentadienyl five-membered rings allows them to retain their single-electron occupation. This approach enables the magnetic properties of 7-AGNR end states to be explored using scanning tunneling microscopy (STM) on a gold substrate. We find a gradual decrease of the magnetic coupling between off-zero mode end states as a function of GNR length, and evolution from a more closed-shell to a more open-shell ground state.
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Affiliation(s)
- Peter
H. Jacobse
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Michael C. Daugherty
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kristia̅ns Čerņevičs
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ziyi Wang
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Ryan D. McCurdy
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Oleg V. Yazyev
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Felix R. Fischer
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bakar
Institute
of Digital Materials for the Planet, Division of Computing, Data Science,
and Society, University of California, Berkeley, California 94720, United States
| | - Michael F. Crommie
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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17
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Zhang W, Xie W, Shao B, Zuo X. Electrically induced net magnetization in FePSe 3 nanoribbons: the role of edge reconstructions. NANOSCALE 2023. [PMID: 38018324 DOI: 10.1039/d3nr04656g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Magnetized edge states of nanoribbon systems open a new path for designing functional spintronic devices. Here, we introduce a general mechanism for electrically generating nonzero net magnetization in antiferromagnetic (AFM) semiconducting nanoribbons. In the proposed spin configuration, in which the empty and occupied edge states of one side close to the Fermi energy are in the same spin channel, the Zeeman-type spin splitting between the states of opposite edges arising from the electric field allow the system to be tuned from the AFM semiconducting phase to the ferromagnetic (FM) metallic phase, yielding nonzero net magnetization. Our ab initio calculations show that this strategy is realizable in the example of the FePSe3 nanoribbon, in which self-passivation-driven reconstruction at the Se termination edge gives rise to the key spin configuration. Moreover, we demonstrate that an electric field could trigger a series of electronic phase transitions among AFM semiconductor, AFM half-metal, and FM metal phases, based on which we were able to design an electronically controllable versatile spintronics device.
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Affiliation(s)
- Wenqi Zhang
- College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China.
| | - Weifeng Xie
- School of Physics and Electronics, Central South University, Changsha 410083, China
| | - Bin Shao
- College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China.
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Nankai University, Tianjin 300350, China
| | - Xu Zuo
- College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China.
- Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin, Nankai University, Tianjin 300350, China
- Engineering Research Center of Thin Film Optoelectronics Technology, Ministry of Education, Nankai University, Tianjin 300350, China
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18
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Dyck O, Almutlaq J, Lingerfelt D, Swett JL, Oxley MP, Huang B, Lupini AR, Englund D, Jesse S. Direct imaging of electron density with a scanning transmission electron microscope. Nat Commun 2023; 14:7550. [PMID: 37985658 PMCID: PMC10662251 DOI: 10.1038/s41467-023-42256-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 07/27/2023] [Indexed: 11/22/2023] Open
Abstract
Recent studies of secondary electron (SE) emission in scanning transmission electron microscopes suggest that material's properties such as electrical conductivity, connectivity, and work function can be probed with atomic scale resolution using a technique known as secondary electron e-beam-induced current (SEEBIC). Here, we apply the SEEBIC imaging technique to a stacked 2D heterostructure device to reveal the spatially resolved electron density of an encapsulated WSe2 layer. We find that the double Se lattice site shows higher emission than the W site, which is at odds with first-principles modelling of valence ionization of an isolated WSe2 cluster. These results illustrate that atomic level SEEBIC contrast within a single material is possible and that an enhanced understanding of atomic scale SE emission is required to account for the observed contrast. In turn, this suggests that, in the future, subtle information about interlayer bonding and the effect on electron orbitals could be directly revealed with this technique.
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Affiliation(s)
- Ondrej Dyck
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | | | - David Lingerfelt
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jacob L Swett
- Biodesign Institute, Arizona State University, Tempe, 87287, AZ, USA
| | - Mark P Oxley
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Bevin Huang
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Andrew R Lupini
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Dirk Englund
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Stephen Jesse
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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19
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Yao X, Zhang H, Kong F, Hinaut A, Pawlak R, Okuno M, Graf R, Horton PN, Coles SJ, Meyer E, Bogani L, Bonn M, Wang HI, Müllen K, Narita A. N=8 Armchair Graphene Nanoribbons: Solution Synthesis and High Charge Carrier Mobility. Angew Chem Int Ed Engl 2023; 62:e202312610. [PMID: 37750665 DOI: 10.1002/anie.202312610] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 09/27/2023]
Abstract
Structurally defined graphene nanoribbons (GNRs) have emerged as promising candidates for nanoelectronic devices. Low band gap (<1 eV) GNRs are particularly important when considering the Schottky barrier in device performance. Here, we demonstrate the first solution synthesis of 8-AGNRs through a carefully designed arylated polynaphthalene precursor. The efficiency of the oxidative cyclodehydrogenation of the tailor-made polymer precursor into 8-AGNRs was validated by FT-IR, Raman, and UV/Vis-near-infrared (NIR) absorption spectroscopy, and further supported by the synthesis of naphtho[1,2,3,4-ghi]perylene derivatives (1 and 2) as subunits of 8-AGNR, with a width of 0.86 nm as suggested by the X-ray single crystal analysis. Low-temperature scanning tunneling microscopy (STM) and solid-state NMR analyses provided further structural support for 8-AGNR. The resulting 8-AGNR exhibited a remarkable NIR absorption extending up to ∼2400 nm, corresponding to an optical band gap as low as ∼0.52 eV. Moreover, optical-pump TeraHertz-probe spectroscopy revealed charge-carrier mobility in the dc limit of ∼270 cm2 V-1 s-1 for the 8-AGNR.
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Affiliation(s)
- Xuelin Yao
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Heng Zhang
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Fanmiao Kong
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Antoine Hinaut
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Rémy Pawlak
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Masanari Okuno
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, 153-8902, Tokyo, Japan
| | - Robert Graf
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Peter N Horton
- National Crystallography Service, School of Chemistry, University of Southampton, SO17 1BJ, Southampton, United Kingdom
| | - Simon J Coles
- National Crystallography Service, School of Chemistry, University of Southampton, SO17 1BJ, Southampton, United Kingdom
| | - Ernst Meyer
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056, Basel, Switzerland
| | - Lapo Bogani
- Department of Materials, University of Oxford, OX1 3PH, Oxford, United Kingdom
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Hai I Wang
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Nanophotonics, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 1, 3584 CC, Utrecht, The Netherlands
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, Ackermannweg10, 55128, Mainz, Germany
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 904-0495, Okinawa, Japan
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20
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Hu T, Zhong W, Zhang T, Wang W, Wang ZF. Identifying topological corner states in two-dimensional metal-organic frameworks. Nat Commun 2023; 14:7092. [PMID: 37925474 PMCID: PMC10625601 DOI: 10.1038/s41467-023-42884-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 10/24/2023] [Indexed: 11/06/2023] Open
Abstract
Due to the diversity of molecular building blocks, the two-dimensional (2D) metal-organic frameworks (MOFs) are ideal platforms to realize exotic lattice models in condensed matter theory. In this work, we demonstrate the universal existence of topological corner states in 2D MOFs with a star lattice configuration, and confirm the intriguing higher-order nontrivial topology in the energy window between two Kagome-bands, or between Dirac-band and four-band. Furthermore, combining first-principles calculations and scanning tunneling microscopy measurements, the unique topological corner state is directly identified in monolayer Ni3(HITP)2 (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) grown on the Au(111) substrate. Our results not only illustrate the first organic topological state in the experiments, but also offer an exciting opportunity to study higher-order topology in 2D MOFs with the large insulating band gap.
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Affiliation(s)
- Tianyi Hu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Weiliang Zhong
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Tingfeng Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Weihua Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Z F Wang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China.
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui, 230088, China.
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21
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Kinikar A, Xu X, Giovannantonio MD, Gröning O, Eimre K, Pignedoli CA, Müllen K, Narita A, Ruffieux P, Fasel R. On-Surface Synthesis of Edge-Extended Zigzag Graphene Nanoribbons. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2306311. [PMID: 37795919 DOI: 10.1002/adma.202306311] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/06/2023] [Indexed: 10/06/2023]
Abstract
Graphene nanoribbons (GNRs) have gained significant attention in nanoelectronics due to their potential for precise tuning of electronic properties through variations in edge structure and ribbon width. However, the synthesis of GNRs with highly sought-after zigzag edges (ZGNRs), critical for spintronics and quantum information technologies, remains challenging. In this study, a design motif for synthesizing a novel class of GNRs termed edge-extended ZGNRs is presented. This motif enables the controlled incorporation of edge extensions along the zigzag edges at regular intervals. The synthesis of a specific GNR instance-a 3-zigzag-rows-wide ZGNR-with bisanthene units fused to the zigzag edges on alternating sides of the ribbon axis is successfully demonstrated. The resulting edge-extended 3-ZGNR is comprehensively characterized for its chemical structure and electronic properties using scanning probe techniques, complemented by density functional theory calculations. The design motif showcased here opens up new possibilities for synthesizing a diverse range of edge-extended ZGNRs, expanding the structural landscape of GNRs and facilitating the exploration of their structure-dependent electronic properties.
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Affiliation(s)
- Amogh Kinikar
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Xiushang Xu
- Okinawa Institute of Science and Technology Graduate University, Organic and Carbon Nanomaterials Unit, 1919-1 Tancha, Onnason, Kunigamigun, Okinawa, 904-0495, Japan
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Marco Di Giovannantonio
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Oliver Gröning
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Kristjan Eimre
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Carlo A Pignedoli
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
- Johannes Gutenberg University Mainz, Institute of Physical Chemistry, Duesbergweg 10-14, 55128, Mainz, Germany
| | - Akimitsu Narita
- Okinawa Institute of Science and Technology Graduate University, Organic and Carbon Nanomaterials Unit, 1919-1 Tancha, Onnason, Kunigamigun, Okinawa, 904-0495, Japan
- Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Pascal Ruffieux
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
| | - Roman Fasel
- Empa, Swiss Federal Laboratories for Materials Science and Technology, nanotech@surfaces Laboratory, Dübendorf, 8600, Switzerland
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern, 3012, Switzerland
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22
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Borin Barin G, Di Giovannantonio M, Lohr TG, Mishra S, Kinikar A, Perrin ML, Overbeck J, Calame M, Feng X, Fasel R, Ruffieux P. On-surface synthesis and characterization of teranthene and hexanthene: ultrashort graphene nanoribbons with mixed armchair and zigzag edges. NANOSCALE 2023; 15:16766-16774. [PMID: 37818609 DOI: 10.1039/d3nr03736c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
Graphene nanoribbons (GNRs) exhibit a broad range of physicochemical properties that critically depend on their width and edge topology. GNRs with armchair edges (AGNRs) are usually more stable than their counterparts with zigzag edges (ZGNRs) where the low-energy spin-polarized edge states render the ribbons prone to being altered by undesired chemical reactions. On the other hand, such edge-localized states make ZGNRs highly appealing for applications in spintronic and quantum technologies. For GNRs fabricated via on-surface synthesis under ultrahigh vacuum conditions on metal substrates, the expected reactivity of zigzag edges is a serious concern in view of substrate transfer and device integration under ambient conditions, but corresponding investigations are scarce. Using 10-bromo-9,9':10',9''-teranthracene as a precursor, we have thus synthesized hexanthene (HA) and teranthene (TA) as model compounds for ultrashort GNRs with mixed armchair and zigzag edges, characterized their chemical and electronic structure by means of scanning probe methods, and studied their chemical reactivity upon air exposure by Raman spectroscopy. We present a detailed identification of molecular orbitals and vibrational modes, assign their origin to armchair or zigzag edges, and discuss the chemical reactivity of these edges based on characteristic Raman spectral features.
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Affiliation(s)
- Gabriela Borin Barin
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
| | - Marco Di Giovannantonio
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
| | - Thorsten G Lohr
- Center for Advancing Electronics Dresden, Department of Chemistry and Food Chemistry, TU Dresden, Dresden 01062, Germany
| | - Shantanu Mishra
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
| | - Amogh Kinikar
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
| | - Mickael L Perrin
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Jan Overbeck
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Michel Calame
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
- Swiss Nanoscience Institute, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Xinliang Feng
- Center for Advancing Electronics Dresden, Department of Chemistry and Food Chemistry, TU Dresden, Dresden 01062, Germany
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - Roman Fasel
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Pascal Ruffieux
- Nanotech@Surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
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23
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Biswas S, Wong J, Pokawanvit S, Yang WCD, Zhang H, Akbari H, Watanabe K, Taniguchi T, Davydov AV, da Jornada FH, Atwater HA. Edge-Confined Excitons in Monolayer Black Phosphorus. ACS NANO 2023. [PMID: 37861986 DOI: 10.1021/acsnano.3c07337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Quantum confinement of two-dimensional excitons in van der Waals materials via electrostatic trapping, lithographic patterning, Moiré potentials, and chemical implantation has enabled significant advances in tailoring light emission from nanostructures. While such approaches rely on complex preparation of materials, natural edges are a ubiquitous feature in layered materials and provide a different approach for investigating quantum-confined excitons. Here, we observe that certain edge sites of monolayer black phosphorus (BP) strongly localize the intrinsic quasi-one-dimensional excitons, yielding sharp spectral lines in photoluminescence, with nearly an order of magnitude line width reduction. Through structural characterization of BP edges using transmission electron microscopy and first-principles GW plus Bethe-Salpeter equation (GW-BSE) calculations of exemplary BP nanoribbons, we find that certain atomic reconstructions can strongly quantum-confine excitons resulting in distinct emission features, mediated by local strain and screening. We observe linearly polarized luminescence emission from edge reconstructions that preserve the mirror symmetry of the parent BP lattice, in agreement with calculations. Furthermore, we demonstrate efficient electrical switching of localized edge excitonic luminescence, whose sites act as excitonic transistors for emission. Localized emission from BP edges motivates exploration of nanoribbons and quantum dots as hosts for tunable narrowband light generation, with future potential to create atomic-like structures for quantum information processing applications as well as exploration of exotic phases that may reside in atomic edge structures.
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Affiliation(s)
- Souvik Biswas
- Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Joeson Wong
- Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Supavit Pokawanvit
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Wei-Chang David Yang
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Huairuo Zhang
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
- Thesis Research, Inc., La Jolla, California 92037, United States
| | - Hamidreza Akbari
- Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute of Materials Science, Tsukuba 305-044, Japan
| | - Takashi Taniguchi
- International Center for Materials, Nanoarchitectonics, National Institute of Materials Science, Tsukuba 305-044, Japan
| | - Albert V Davydov
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Felipe H da Jornada
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Harry A Atwater
- Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125, United States
- Kavli Nanoscience Institute, Pasadena, California 91125, United States
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24
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Porto JAS, Beserra DJP, de Vasconcelos FM, Silva PV, Girão EC. Electronic properties and carrier mobilities of nanocarbons formed by non-benzoidal building blocks. Phys Chem Chem Phys 2023; 25:27053-27064. [PMID: 37791620 DOI: 10.1039/d3cp01436c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Exotic 1D and 2D carbon nanostructures have been grown in the laboratory in the last few years by means of surface-assisted chemical routes. In these processes, the strategical choice of a molecular precursor plays a dominant role in the determination of the synthesized nanocarbon. Further variations of these techniques are able to produce non-benzoidal carbon quantum-dots (QDs). Considering this experimental scenario as motivation, we propose a series of nanoribbon systems based on concatenating recently synthesized carbon QDs containing pentagonal, hexagonal, and heptagonal rings. We use density functional theory (DFT) simulations to reveal their properties can range from metallic to semiconducting depending on the concatenation hierarchy used to form the nanoribbons. This DFT implementation is based on a LCAO approach to describe valence wavefunctions and most of the simulations employ the PBE-GGA functional. Since this functional is known to underestimate band gaps, we also use the B3LYP functional in a plane-wave DFT approach for a selected case for comparison purposes. These systems show a different gap versus width relationship compared to conventional graphene nanoribbons setups and a particular set of carrier mobility values. We further discuss the interplay between the QD's frontier states and the electronic properties of the nanoribbons in light of their structural details.
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Affiliation(s)
- João Alberto Santos Porto
- Programa de Pós-Graduacão em Ciência e Engenharia dos Materiais, Universidade Federal do Piauí, CEP 64049-550, Teresina, PI, Brazil.
- Universidade Estadual do Maranhão - UEMA, Departamento de Matemática e Física - Campus Caxias, CEP 65604-380, Caxias, Maranhão, Brazil
| | - David Joseph Pereira Beserra
- Instituto Federal de Educação, Ciência e Tecnologia do Maranhão - Campus Buriticupu, CEP 65393-000, Buriticupu, Maranhão, Brazil
| | - Fabrício Morais de Vasconcelos
- Instituto Federal de Educação, Ciência e Tecnologia do Piauí - Campus São João do PI, CEP 64760-000, São João do PI, Piauí, Brazil
| | - Paloma Vieira Silva
- Coordenação do Curso de Licenciatura em Educação do Campo/Ciências da Natureza, Universidade Federal do Piauí, CEP 64808-605, Floriano, Piauí, Brazil
| | - Eduardo Costa Girão
- Programa de Pós-Graduacão em Ciência e Engenharia dos Materiais, Universidade Federal do Piauí, CEP 64049-550, Teresina, PI, Brazil.
- Departamento de Física, Universidade Federal do Piauí, CEP 64049-550, Teresina, Piauí, Brazil
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25
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Huang W, Braun O, Indolese DI, Barin GB, Gandus G, Stiefel M, Olziersky A, Müllen K, Luisier M, Passerone D, Ruffieux P, Schönenberger C, Watanabe K, Taniguchi T, Fasel R, Zhang J, Calame M, Perrin ML. Edge Contacts to Atomically Precise Graphene Nanoribbons. ACS NANO 2023; 17:18706-18715. [PMID: 37578964 PMCID: PMC10569104 DOI: 10.1021/acsnano.3c00782] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 08/08/2023] [Indexed: 08/16/2023]
Abstract
Bottom-up-synthesized graphene nanoribbons (GNRs) are an emerging class of designer quantum materials that possess superior properties, including atomically controlled uniformity and chemically tunable electronic properties. GNR-based devices are promising candidates for next-generation electronic, spintronic, and thermoelectric applications. However, due to their extremely small size, making electrical contact with GNRs remains a major challenge. Currently, the most commonly used methods are top metallic electrodes and bottom graphene electrodes, but for both, the contact resistance is expected to scale with overlap area. Here, we develop metallic edge contacts to contact nine-atom-wide armchair GNRs (9-AGNRs) after encapsulation in hexagonal boron-nitride (h-BN), resulting in ultrashort contact lengths. We find that charge transport in our devices occurs via two different mechanisms: at low temperatures (9 K), charges flow through single GNRs, resulting in quantum dot (QD) behavior with well-defined Coulomb diamonds (CDs), with addition energies in the range of 16 to 400 meV. For temperatures above 100 K, a combination of temperature-activated hopping and polaron-assisted tunneling takes over, with charges being able to flow through a network of 9-AGNRs across distances significantly exceeding the length of individual GNRs. At room temperature, our short-channel field-effect transistor devices exhibit on/off ratios as high as 3 × 105 with on-state current up to 50 nA at 0.2 V. Moreover, we find that the contact performance of our edge-contact devices is comparable to that of top/bottom contact geometries but with a significantly reduced footprint. Overall, our work demonstrates that 9-AGNRs can be contacted at their ends in ultra-short-channel FET devices while being encapsulated in h-BN.
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Affiliation(s)
- Wenhao Huang
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Physics, University of Basel, 4056 Basel, Switzerland
| | - Oliver Braun
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Physics, University of Basel, 4056 Basel, Switzerland
| | | | - Gabriela Borin Barin
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Guido Gandus
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Michael Stiefel
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | | | - Klaus Müllen
- Max Planck
Institute for Polymer Research, 55128 Mainz, Germany
| | - Mathieu Luisier
- Department
of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
- Quantum Center, ETH Zürich, 8093 Zürich, Switzerland
| | - Daniele Passerone
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Pascal Ruffieux
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | | | - Kenji Watanabe
- Research
Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- Research
Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Roman Fasel
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Chemistry, Biochemistry and Pharmaceutical Science, University of Bern, 3012 Bern, Switzerland
| | - Jian Zhang
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Michel Calame
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Physics, University of Basel, 4056 Basel, Switzerland
- Swiss Nanoscience
Institute, University of Basel, 4056 Basel, Switzerland
| | - Mickael L. Perrin
- Transport
at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
- Quantum Center, ETH Zürich, 8093 Zürich, Switzerland
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26
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Zhang JJ, Liu K, Xiao Y, Yu X, Huang L, Gao HJ, Ma J, Feng X. Precision Graphene Nanoribbon Heterojunctions by Chain-Growth Polymerization. Angew Chem Int Ed Engl 2023; 62:e202310880. [PMID: 37594477 DOI: 10.1002/anie.202310880] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/19/2023]
Abstract
Graphene nanoribbons (GNRs) are considered promising candidates for next-generation nanoelectronics. In particular, GNR heterojunctions have received considerable attention due to their exotic topological electronic phases at the heterointerface. However, strategies for their precision synthesis remain at a nascent stage. Here, we report a novel chain-growth polymerization strategy that allows for constructing GNR heterojunction with N=9 armchair and chevron GNRs segments (9-AGNR/cGNR). The synthesis involves a controlled Suzuki-Miyaura catalyst-transfer polymerization (SCTP) between 2-(6'-bromo-4,4''-ditetradecyl-[1,1':2',1''-terphenyl]-3'-yl) boronic ester (M1) and 2-(7-bromo-9,12-diphenyl-10,11-bis(4-tetradecylphenyl)-triphenylene-2-yl) boronic ester (M2), followed by the Scholl reaction of the obtained block copolymer (poly-M1/M2) with controlled Mn (18 kDa) and narrow Đ (1.45). NMR and SEC analysis of poly-M1/M2 confirm the successful block copolymerization. The solution-mediated cyclodehydrogenation of poly-M1/M2 toward 9-AGNR/cGNR is unambiguously validated by FT-IR, Raman, and UV/Vis spectroscopies. Moreover, we also demonstrate the on-surface formation of pristine 9-AGNR/cGNR from the unsubstituted copolymer precursor, which is unambiguously characterized by scanning tunneling microscopy (STM).
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Affiliation(s)
- Jin-Jiang Zhang
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120, Halle, Germany
| | - Kun Liu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstrasse 4, 01062, Dresden, Germany
| | - Yao Xiao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Xiuling Yu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstrasse 4, 01062, Dresden, Germany
| | - Li Huang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Hong-Jun Gao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, 100190, Beijing, China
| | - Ji Ma
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120, Halle, Germany
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstrasse 4, 01062, Dresden, Germany
| | - Xinliang Feng
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120, Halle, Germany
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstrasse 4, 01062, Dresden, Germany
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27
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Dyck O, Lupini AR, Jesse S. A Platform for Atomic Fabrication and In Situ Synthesis in a Scanning Transmission Electron Microscope. SMALL METHODS 2023; 7:e2300401. [PMID: 37415539 DOI: 10.1002/smtd.202300401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/30/2023] [Indexed: 07/08/2023]
Abstract
The engineering of quantum materials requires the development of tools able to address various synthesis and characterization challenges. These include the establishment and refinement of growth methods, material manipulation, and defect engineering. Atomic-scale modification will be a key enabling factor for engineering quantum materials where desired phenomena are critically determined by atomic structures. Successful use of scanning transmission electron microscopes (STEMs) for atomic scale material manipulation has opened the door for a transformed view of what can be accomplished using electron-beam-based strategies. However, serious obstacles exist on the pathway from possibility to practical reality. One such obstacle is the in situ delivery of atomized material in the STEM to the region of interest for further fabrication processes. Here, progress on this front is presented with a view toward performing synthesis (deposition and growth) processes in a scanning transmission electron microscope in combination with top-down control over the reaction region. An in situ thermal deposition platform is presented, tested, and deposition and growth processes are demonstrated. In particular, it is shown that isolated Sn atoms can be evaporated from a filament and caught on the nearby sample, demonstrating atomized material delivery. This platform is envisioned to facilitate real-time atomic resolution imaging of growth processes and open new pathways toward atomic fabrication.
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Affiliation(s)
- Ondrej Dyck
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN, 37830, USA
| | - Andrew R Lupini
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN, 37830, USA
| | - Stephen Jesse
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN, 37830, USA
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28
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Kuo DMT. Thermal rectification through the topological states of asymmetrical length armchair graphene nanoribbons heterostructures with vacancies. NANOTECHNOLOGY 2023; 34:505401. [PMID: 37703858 DOI: 10.1088/1361-6528/acf93a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 09/12/2023] [Indexed: 09/15/2023]
Abstract
We present a theoretical investigation of electron heat current in asymmetrical length armchair graphene nanoribbon (AGNR) heterostructures with vacancies, focusing on the topological states (TSs). In particular, we examine the 9-7-9 AGNR heterostructures where the TSs are well-isolated from the conduction and valence subbands. This isolation effectively mitigates thermal noise of subbands arising from temperature fluctuations during charge transport. Moreover, when the TSs exhibit an orbital off-set, intriguing electron heat rectification phenomena are observed, primarily attributed to inter-TS electron Coulomb interactions. To enhance the heat rectification ratio (ηQ), we manipulate the coupling strengths between the heat sources and the TSs by introducing asymmetrical lengths in the 9-AGNRs. This approach offers control over the rectification properties, enabling significant enhancements. Additionally, we introduce vacancies strategically positioned between the heat sources and the TSs to suppress phonon heat current. This arrangement effectively reduces the overall phonon heat current, while leaving the TSs unaffected. Our findings provide valuable insights into the behavior of electron heat current in AGNR heterostructures, highlighting the role of topological states, inter-TS electron Coulomb interactions, and the impact of structural modifications such as asymmetrical lengths and vacancy positioning. These results pave the way for the design and optimization of graphene-based devices with improved thermal management and efficient control of electron heat transport.
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Affiliation(s)
- David M T Kuo
- Department of Electrical Engineering and Department of Physics, National Central University, Chungli, 320, Taiwan
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29
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Zhang J, Barin GB, Furrer R, Du CZ, Wang XY, Müllen K, Ruffieux P, Fasel R, Calame M, Perrin ML. Determining the Number of Graphene Nanoribbons in Dual-Gate Field-Effect Transistors. NANO LETTERS 2023; 23:8474-8480. [PMID: 37671914 PMCID: PMC10540264 DOI: 10.1021/acs.nanolett.3c01931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/29/2023] [Indexed: 09/07/2023]
Abstract
Bottom-up synthesized graphene nanoribbons (GNRs) are increasingly attracting interest due to their atomically controlled structure and customizable physical properties. In recent years, a range of GNR-based field-effect transistors (FETs) has been fabricated, with several demonstrating quantum-dot (QD) behavior at cryogenic temperatures. However, understanding the relationship between the cryogenic charge-transport characteristics and the number of the GNRs in the device is challenging, as the length and location of the GNRs in the junction are not precisely controlled. Here, we present a methodology based on a dual-gate FET that allows us to identify different scenarios, such as single GNRs, double or multiple GNRs in parallel, and a single GNR interacting with charge traps. Our dual-gate FET architecture therefore offers a quantitative approach for comprehending charge transport in atomically precise GNRs.
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Affiliation(s)
- Jian Zhang
- Transport
at Nanoscale Interfaces Laboratory, Empa
Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Gabriela Borin Barin
- nanotech@surfaces
Laboratory, Empa Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Roman Furrer
- Transport
at Nanoscale Interfaces Laboratory, Empa
Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Cheng-Zhuo Du
- State
Key Laboratory of Elemento-Organic Chemistry College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Xiao-Ye Wang
- State
Key Laboratory of Elemento-Organic Chemistry College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Klaus Müllen
- Max
Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Pascal Ruffieux
- nanotech@surfaces
Laboratory, Empa Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Roman Fasel
- nanotech@surfaces
Laboratory, Empa Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Chemistry Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Michel Calame
- Transport
at Nanoscale Interfaces Laboratory, Empa
Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Physics, University of Basel, 4056 Basel, Switzerland
- Swiss
Nanoscience Institute, University of Basel, 4056 Basel, Switzerland
| | - Mickael L. Perrin
- Transport
at Nanoscale Interfaces Laboratory, Empa
Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
- Quantum
Center, ETH Zürich, 8093 Zürich, Switzerland
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30
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Yin R, Wang Z, Tan S, Ma C, Wang B. On-Surface Synthesis of Graphene Nanoribbons with Atomically Precise Structural Heterogeneities and On-Site Characterizations. ACS NANO 2023; 17:17610-17623. [PMID: 37666005 DOI: 10.1021/acsnano.3c06128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Graphene nanoribbons (GNRs) are strips of graphene, with widths of a few nanometers, that are promising candidates for future applications in nanodevices and quantum information processing due to their highly tunable structure-dependent electronic, spintronic, topological, and optical properties. Implantation of periodic structural heterogeneities, such as heteroatoms, nanopores, and non-hexagonal rings, has become a powerful manner for tailoring the designer properties of GNRs. The bottom-up synthesis approach, by combining on-surface chemical reactions based on rationally designed molecular precursors and in situ tip-based microscopic and spectroscopic techniques, promotes the construction of atomically precise GNRs with periodic structural modulations. However, there are still obstacles and challenges lying on the way toward the understanding of the intrinsic structure-property relations, such as the strong screening and Fermi level pinning effect of the normally used transition metal substrates and the lack of collective tip-based techniques that can cover multi-internal degrees of freedom of the GNRs. In this Perspective, we briefly review the recent progress in the on-surface synthesis of GNRs with diverse structural heterogeneities and highlight the structure-property relations as characterized by the noncontact atomic force microscopy and scanning tunneling microscopy/spectroscopy. We furthermore motivate to deliver the need for developing strategies to achieve quasi-freestanding GNRs and for exploiting multifunctional tip-based techniques to collectively probe the intrinsic properties.
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Affiliation(s)
- Ruoting Yin
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhengya Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Shijing Tan
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Chuanxu Ma
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Bing Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, New Cornerstone Science Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
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31
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Seibel J, Fittolani G, Mirhosseini H, Wu X, Rauschenbach S, Anggara K, Seeberger PH, Delbianco M, Kühne TD, Schlickum U, Kern K. Visualizing Chiral Interactions in Carbohydrates Adsorbed on Au(111) by High-Resolution STM Imaging. Angew Chem Int Ed Engl 2023; 62:e202305733. [PMID: 37522820 DOI: 10.1002/anie.202305733] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/03/2023] [Accepted: 07/31/2023] [Indexed: 08/01/2023]
Abstract
Carbohydrates are the most abundant organic material on Earth and the structural "material of choice" in many living systems. Nevertheless, design and engineering of synthetic carbohydrate materials presently lag behind that for protein and nucleic acids. Bottom-up engineering of carbohydrate materials demands an atomic-level understanding of their molecular structures and interactions in condensed phases. Here, high-resolution scanning tunneling microscopy (STM) is used to visualize at submolecular resolution the three-dimensional structure of cellulose oligomers assembled on Au(1111) and the interactions that drive their assembly. The STM imaging, supported by ab initio calculations, reveals the orientation of all glycosidic bonds and pyranose rings in the oligomers, as well as details of intermolecular interactions between the oligomers. By comparing the assembly of D- and L-oligomers, these interactions are shown to be enantioselective, capable of driving spontaneous enantioseparation of cellulose chains from its unnatural enantiomer and promoting the formation of engineered carbohydrate assemblies in the condensed phases.
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Affiliation(s)
- Johannes Seibel
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
- Institute of Applied Physics and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, 38104, Braunschweig, Germany
- Current address: Institute of Physical Chemistry, Karlsruhe Institute of Technology (KIT), 76131, Karlsruhe, Germany
| | - Giulio Fittolani
- Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Free University Berlin, 14195, Berlin, Germany
| | - Hossein Mirhosseini
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Chair of Theoretical Chemistry, University of Paderborn, 33098, Paderborn, Germany
| | - Xu Wu
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
| | - Stephan Rauschenbach
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
- Department of Chemistry, University of Oxford, OX13TA, Oxford, UK
| | - Kelvin Anggara
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
| | - Peter H Seeberger
- Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Free University Berlin, 14195, Berlin, Germany
| | - Martina Delbianco
- Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
| | - Thomas D Kühne
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Chair of Theoretical Chemistry, University of Paderborn, 33098, Paderborn, Germany
- Center for Advanced Systems Understanding (CASUS) and Helmholtz Zentrum Dresden-Rossendorf, 02826, Görlitz, Germany
| | - Uta Schlickum
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
- Institute of Applied Physics and Laboratory for Emerging Nanometrology, Technische Universität Braunschweig, 38104, Braunschweig, Germany
| | - Klaus Kern
- Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany
- Institut de Physique, École Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
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32
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Fu W, John M, Maddumapatabandi TD, Bussolotti F, Yau YS, Lin M, Johnson Goh KE. Toward Edge Engineering of Two-Dimensional Layered Transition-Metal Dichalcogenides by Chemical Vapor Deposition. ACS NANO 2023; 17:16348-16368. [PMID: 37646426 DOI: 10.1021/acsnano.3c04581] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The manipulation of edge configurations and structures in atomically-thin transition metal dichalcogenides (TMDs) for versatile functionalization has attracted intensive interest in recent years. The chemical vapor deposition (CVD) approach has shown promise for TMD edge engineering of atomic edge configurations (1H, 1T or 1T'-zigzag or armchair edges) as well as diverse edge morphologies (1D nanoribbons, 2D dendrites, 3D spirals, etc.). These edge-rich TMD layers offer versatile candidates for probing the physical and chemical properties and exploring potential applications in electronics, optoelectronics, catalysis, sensing, and quantum technologies. In this Review, we present an overview of the current state-of-the-art in the manipulation of TMD atomic edges and edge-rich structures using CVD. We highlight the vast range of distinct properties associated with these edge configurations and structures and provide insights into the opportunities afforded by such edge-functionalized crystals. The objective of this Review is to motivate further research and development efforts to use CVD as a scalable approach to harness the benefits of such crystal-edge engineering.
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Affiliation(s)
- Wei Fu
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
| | - Mark John
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
- Department of Physics, National University of Singapore, 2 Science Drive 3 117551, Singapore
| | - Thathsara D Maddumapatabandi
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
| | - Fabio Bussolotti
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
| | - Yong Sean Yau
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
| | - Ming Lin
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
| | - Kuan Eng Johnson Goh
- Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03 138634, Singapore
- Department of Physics, National University of Singapore, 2 Science Drive 3 117551, Singapore
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue 639798, Singapore
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33
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Wen EH, Jacobse PH, Jiang J, Wang Z, Louie SG, Crommie MF, Fischer FR. Fermi-Level Engineering of Nitrogen Core-Doped Armchair Graphene Nanoribbons. J Am Chem Soc 2023; 145:19338-19346. [PMID: 37611208 PMCID: PMC10485924 DOI: 10.1021/jacs.3c05755] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Indexed: 08/25/2023]
Abstract
Substitutional heteroatom doping of bottom-up engineered 1D graphene nanoribbons (GNRs) is a versatile tool for realizing low-dimensional functional materials for nanoelectronics and sensing. Previous efforts have largely relied on replacing C-H groups lining the edges of GNRs with trigonal planar N atoms. This type of atomically precise doping, however, only results in a modest realignment of the valence band (VB) and conduction band (CB) energies. Here, we report the design, bottom-up synthesis, and spectroscopic characterization of nitrogen core-doped 5-atom-wide armchair GNRs (N2-5-AGNRs) that yield much greater energy-level shifting of the GNR electronic structure. Here, the substitution of C atoms with N atoms along the backbone of the GNR introduces a single surplus π-electron per dopant that populates the electronic states associated with previously unoccupied bands. First-principles DFT-LDA calculations confirm that a sizable shift in Fermi energy (∼1.0 eV) is accompanied by a broad reconfiguration of the band structure, including the opening of a new band gap and the transition from a direct to an indirect semiconducting band gap. Scanning tunneling spectroscopy (STS) lift-off charge transport experiments corroborate the theoretical results and reveal the relationship among substitutional heteroatom doping, Fermi-level shifting, electronic band structure, and topological engineering for this new N-doped GNR.
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Affiliation(s)
- Ethan
Chi Ho Wen
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Peter H. Jacobse
- Department
of Physics, University of California, Berkeley, California 94720, United States
| | - Jingwei Jiang
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Ziyi Wang
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Steven G. Louie
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Michael F. Crommie
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California Berkeley
and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Felix R. Fischer
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kavli
Energy NanoSciences Institute at the University of California Berkeley
and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bakar
Institute of Digital Materials for the Planet, Division of Computing,
Data Science, and Society, University of
California, Berkeley, California 94720, United States
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34
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Li L, Prindle CR, Shi W, Nuckolls C, Venkataraman L. Radical Single-Molecule Junctions. J Am Chem Soc 2023; 145:18182-18204. [PMID: 37555594 DOI: 10.1021/jacs.3c04487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Radicals are unique molecular systems for applications in electronic devices due to their open-shell electronic structures. Radicals can function as good electrical conductors and switches in molecular circuits while also holding great promise in the field of molecular spintronics. However, it is both challenging to create stable, persistent radicals and to understand their properties in molecular junctions. The goal of this Perspective is to address this dual challenge by providing design principles for the synthesis of stable radicals relevant to molecular junctions, as well as offering current insight into the electronic properties of radicals in single-molecule devices. By exploring both the chemical and physical properties of established radical systems, we will facilitate increased exploration and development of radical-based molecular systems.
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Affiliation(s)
- Liang Li
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Claudia R Prindle
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Wanzhuo Shi
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York 10027, United States
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
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35
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Obermann S, Zheng W, Melidonie J, Böckmann S, Osella S, Arisnabarreta N, Guerrero-León LA, Hennersdorf F, Beljonne D, Weigand JJ, Bonn M, De Feyter S, Hansen MR, Wang HI, Ma J, Feng X. Curved graphene nanoribbons derived from tetrahydropyrene-based polyphenylenes via one-pot K-region oxidation and Scholl cyclization. Chem Sci 2023; 14:8607-8614. [PMID: 37592977 PMCID: PMC10430550 DOI: 10.1039/d3sc02824k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 06/19/2023] [Indexed: 08/19/2023] Open
Abstract
Precise synthesis of graphene nanoribbons (GNRs) is of great interest to chemists and materials scientists because of their unique opto-electronic properties and potential applications in carbon-based nanoelectronics and spintronics. In addition to the tunable edge structure and width, introducing curvature in GNRs is a powerful structural feature for their chemi-physical property modification. Here, we report an efficient solution synthesis of the first pyrene-based GNR (PyGNR) with curved geometry via one-pot K-region oxidation and Scholl cyclization of its corresponding well-soluble tetrahydropyrene-based polyphenylene precursor. The efficient A2B2-type Suzuki polymerization and subsequent Scholl reaction furnishes up to ∼35 nm long curved GNRs bearing cove- and armchair-edges. The construction of model compound 1, as a cutout of PyGNR, from a tetrahydropyrene-based oligophenylene precursor proves the concept and efficiency of the one-pot K-region oxidation and Scholl cyclization, which is clearly revealed by single crystal X-ray diffraction analysis. The structure and optical properties of PyGNR are investigated by Raman, FT-IR, solid-state NMR, STM and UV-Vis analysis with the support of DFT calculations. PyGNR exhibits a narrow optical bandgap of ∼1.4 eV derived from a Tauc plot, qualifying as a low-bandgap GNR. Moreover, THz spectroscopy on PyGNR estimates its macroscopic charge mobility μ as ∼3.6 cm2 V-1 s-1, outperforming several other curved GNRs reported via conventional Scholl reaction.
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Affiliation(s)
- Sebastian Obermann
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden D-01069 Dresden Germany
| | - Wenhao Zheng
- Max-Planck-Institute for Polymer Research D-55128 Mainz Germany
| | - Jason Melidonie
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden D-01069 Dresden Germany
| | - Steffen Böckmann
- Institute of Physical Chemistry, Westfählische Wilhelms-Universität (WWU) Münster D-48149 Münster Germany
| | - Silvio Osella
- Chemical and Biological Systems Simulation Lab, Centre of New Technologies University of Warsaw Banacha 2C Warsaw 02-097 Poland
| | - Nicolás Arisnabarreta
- Department of Chemistry, Division of Molecular Imaging and Photonics, KU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - L Andrés Guerrero-León
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden D-01069 Dresden Germany
| | - Felix Hennersdorf
- Chair of Inorganic Molecular Chemistry, Technische Universität Dresden Dresden Germany
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, Materials Research Institute, University of Mons Mons 7000 Belgium
| | - Jan J Weigand
- Chair of Inorganic Molecular Chemistry, Technische Universität Dresden Dresden Germany
| | - Mischa Bonn
- Max-Planck-Institute for Polymer Research D-55128 Mainz Germany
| | - Steven De Feyter
- Department of Chemistry, Division of Molecular Imaging and Photonics, KU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Michael Ryan Hansen
- Institute of Physical Chemistry, Westfählische Wilhelms-Universität (WWU) Münster D-48149 Münster Germany
| | - Hai I Wang
- Max-Planck-Institute for Polymer Research D-55128 Mainz Germany
| | - Ji Ma
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden D-01069 Dresden Germany
- Max Planck Institute of Microstructure Physics Weinberg 2 06120 Halle Germany
| | - Xinliang Feng
- Center for Advancing Electronics Dresden (cfaed), Faculty of Chemistry and Food Chemistry, Technische Universität Dresden D-01069 Dresden Germany
- Max Planck Institute of Microstructure Physics Weinberg 2 06120 Halle Germany
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36
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Zhang J, Qian L, Barin GB, Daaoub AHS, Chen P, Müllen K, Sangtarash S, Ruffieux P, Fasel R, Sadeghi H, Zhang J, Calame M, Perrin ML. Contacting individual graphene nanoribbons using carbon nanotube electrodes. NATURE ELECTRONICS 2023; 6:572-581. [PMID: 37636241 PMCID: PMC10449622 DOI: 10.1038/s41928-023-00991-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 06/09/2023] [Indexed: 08/29/2023]
Abstract
Graphene nanoribbons synthesized using bottom-up approaches can be structured with atomic precision, allowing their physical properties to be precisely controlled. For applications in quantum technology, the manipulation of single charges, spins or photons is required. However, achieving this at the level of single graphene nanoribbons is experimentally challenging due to the difficulty of contacting individual nanoribbons, particularly on-surface synthesized ones. Here we report the contacting and electrical characterization of on-surface synthesized graphene nanoribbons in a multigate device architecture using single-walled carbon nanotubes as the electrodes. The approach relies on the self-aligned nature of both nanotubes, which have diameters as small as 1 nm, and the nanoribbon growth on their respective growth substrates. The resulting nanoribbon-nanotube devices exhibit quantum transport phenomena-including Coulomb blockade, excited states of vibrational origin and Franck-Condon blockade-that indicate the contacting of individual graphene nanoribbons.
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Affiliation(s)
- Jian Zhang
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | - Liu Qian
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Gabriela Borin Barin
- nanotech@surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | | | - Peipei Chen
- Nanofabrication Laboratory, National Center for Nanoscience and Technology, Beijing, China
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Mainz, Germany
| | | | - Pascal Ruffieux
- nanotech@surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | - Roman Fasel
- nanotech@surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Hatef Sadeghi
- School of Engineering, University of Warwick, Coventry, UK
| | - Jin Zhang
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Michel Calame
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Department of Physics, University of Basel, Basel, Switzerland
- Swiss Nanoscience Institute, University of Basel, Basel, Switzerland
| | - Mickael L. Perrin
- Transport at Nanoscale Interfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland
- Quantum Center, ETH Zurich, Zurich, Switzerland
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37
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Bouwmeester D, Ghiasi TS, Borin Barin G, Müllen K, Ruffieux P, Fasel R, van der Zant HSJ. MoRe Electrodes with 10 nm Nanogaps for Electrical Contact to Atomically Precise Graphene Nanoribbons. ACS APPLIED NANO MATERIALS 2023; 6:13935-13944. [PMID: 37588262 PMCID: PMC10425920 DOI: 10.1021/acsanm.3c01630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/28/2023] [Indexed: 08/18/2023]
Abstract
Atomically precise graphene nanoribbons (GNRs) are predicted to exhibit exceptional edge-related properties, such as localized edge states, spin polarization, and half-metallicity. However, the absence of low-resistance nanoscale electrical contacts to the GNRs hinders harnessing their properties in field-effect transistors. In this paper, we make electrical contact with nine-atom-wide armchair GNRs using superconducting alloy MoRe as well as Pd (as a reference), which are two of the metals providing low-resistance contacts to carbon nanotubes. We take a step toward contacting a single GNR by fabricating electrodes with needlelike geometry, with about 20 nm tip diameter and 10 nm separation. To preserve the nanoscale geometry of the contacts, we develop a PMMA-assisted technique to transfer the GNRs onto the prepatterned electrodes. Our device characterizations as a function of bias voltage and temperature show thermally activated gate-tunable conductance in GNR-MoRe-based transistors.
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Affiliation(s)
- Damian Bouwmeester
- Kavli
Institute of Nanoscience, Delft University
of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Talieh S. Ghiasi
- Kavli
Institute of Nanoscience, Delft University
of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Gabriela Borin Barin
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Klaus Müllen
- Max
Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Pascal Ruffieux
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Roman Fasel
- nanotech@surfaces
Laboratory, Empa, Swiss Federal Laboratories
for Materials Science and Technology, 8600 Dübendorf, Switzerland
- Department
of Chemistry, Biochemistry and Pharmaceutical Chemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Herre S. J. van der Zant
- Kavli
Institute of Nanoscience, Delft University
of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
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38
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Du Q, Su X, Liu Y, Jiang Y, Li C, Yan K, Ortiz R, Frederiksen T, Wang S, Yu P. Orbital-symmetry effects on magnetic exchange in open-shell nanographenes. Nat Commun 2023; 14:4802. [PMID: 37558678 PMCID: PMC10412602 DOI: 10.1038/s41467-023-40542-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 08/01/2023] [Indexed: 08/11/2023] Open
Abstract
Open-shell nanographenes appear as promising candidates for future applications in spintronics and quantum technologies. A critical aspect to realize this potential is to design and control the magnetic exchange. Here, we reveal the effects of frontier orbital symmetries on the magnetic coupling in diradical nanographenes through scanning probe microscope measurements and different levels of theoretical calculations. In these open-shell nanographenes, the exchange energy exhibits a remarkable variation between 20 and 160 meV. Theoretical calculations reveal that frontier orbital symmetries play a key role in affecting the magnetic coupling on such a large scale. Moreover, a triradical nanographene is demonstrated for investigating the magnetic interaction among three unpaired electrons with unequal magnetic exchange, in agreement with Heisenberg spin model calculations. Our results provide insights into both theoretical design and experimental realization of nanographene materials with different exchange interactions through tuning the orbital symmetry, potentially useful for realizing magnetically operable graphene-based nanomaterials.
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Affiliation(s)
- Qingyang Du
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Xuelei Su
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Yufeng Liu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yashi Jiang
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Can Li
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - KaKing Yan
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Ricardo Ortiz
- Donostia International Physics Center (DIPC) - UPV/EHU, 20018, San Sebastián, Spain.
| | - Thomas Frederiksen
- Donostia International Physics Center (DIPC) - UPV/EHU, 20018, San Sebastián, Spain.
- IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain.
| | - Shiyong Wang
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Ping Yu
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China.
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Tepliakov NV, Ma R, Lischner J, Kaxiras E, Mostofi AA, Pizzochero M. Dirac Half-Semimetallicity and Antiferromagnetism in Graphene Nanoribbon/Hexagonal Boron Nitride Heterojunctions. NANO LETTERS 2023; 23:6698-6704. [PMID: 37459271 DOI: 10.1021/acs.nanolett.3c01940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Half-metals have been envisioned as active components in spintronic devices by virtue of their completely spin-polarized electrical currents. Actual materials hosting half-metallic phases, however, remain scarce. Here, we predict that recently fabricated heterojunctions of zigzag nanoribbons embedded in two-dimensional hexagonal boron nitride are half-semimetallic, featuring fully spin-polarized Dirac points at the Fermi level. The half-semimetallicity originates from the transfer of charges from hexagonal boron nitride to the embedded graphene nanoribbon. These charges give rise to opposite energy shifts of the states residing at the two edges, while preserving their intrinsic antiferromagnetic exchange coupling. Upon doping, an antiferromagnetic-to-ferrimagnetic phase transition occurs in these heterojunctions, with the sign of the excess charge controlling the spatial localization of the net magnetic moments. Our findings demonstrate that such heterojunctions realize tunable one-dimensional conducting channels of spin-polarized Dirac fermions seamlessly integrated into a two-dimensional insulator, thus holding promise for the development of carbon-based spintronics.
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Affiliation(s)
- Nikita V Tepliakov
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Ruize Ma
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
- Department of Physics, University of Oxford, Oxford OX1 2JD, United Kingdom
| | - Johannes Lischner
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Efthimios Kaxiras
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Arash A Mostofi
- Departments of Materials and Physics, Imperial College London, London SW7 2AZ, United Kingdom
- The Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Michele Pizzochero
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
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40
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Paudel RK, Ren CY, Chang YC. Semi-Empirical Pseudopotential Method for Graphene and Graphene Nanoribbons. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2066. [PMID: 37513077 PMCID: PMC10383570 DOI: 10.3390/nano13142066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/06/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023]
Abstract
We implemented a semi-empirical pseudopotential (SEP) method for calculating the band structures of graphene and graphene nanoribbons. The basis functions adopted are two-dimensional plane waves multiplied by several B-spline functions along the perpendicular direction. The SEP includes both local and non-local terms, which were parametrized to fit relevant quantities obtained from the first-principles calculations based on the density-functional theory (DFT). With only a handful of parameters, we were able to reproduce the full band structure of graphene obtained by DFT with a negligible difference. Our method is simple to use and much more efficient than the DFT calculation. We then applied this SEP method to calculate the band structures of graphene nanoribbons. By adding a simple correction term to the local pseudopotentials on the edges of the nanoribbon (which mimics the effect caused by edge creation), we again obtained band structures of the armchair nanoribbon fairly close to the results obtained by DFT. Our approach allows the simulation of optical and transport properties of realistic nanodevices made of graphene nanoribbons with very little computation effort.
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Affiliation(s)
- Raj Kumar Paudel
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
- Molecular Science and Technology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
- Department of Physics, National Central University, Chungli 320, Taiwan
| | - Chung-Yuan Ren
- Department of Physics, National Kaohsiung Normal University, Kaohsiung 824, Taiwan
| | - Yia-Chung Chang
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
- Department of Physics, National Cheng-Kung University, Tainan 701, Taiwan
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41
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McCurdy RD, Delgado A, Jiang J, Zhu J, Wen ECH, Blackwell RE, Veber GC, Wang S, Louie SG, Fischer FR. Engineering Robust Metallic Zero-Mode States in Olympicene Graphene Nanoribbons. J Am Chem Soc 2023. [PMID: 37428750 PMCID: PMC10360063 DOI: 10.1021/jacs.3c01576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
Metallic graphene nanoribbons (GNRs) represent a critical component in the toolbox of low-dimensional functional materials technology serving as 1D interconnects capable of both electronic and quantum information transport. The structural constraints imposed by on-surface bottom-up GNR synthesis protocols along with the limited control over orientation and sequence of asymmetric monomer building blocks during the radical step-growth polymerization have plagued the design and assembly of metallic GNRs. Here, we report the regioregular synthesis of GNRs hosting robust metallic states by embedding a symmetric zero-mode (ZM) superlattice along the backbone of a GNR. Tight-binding electronic structure models predict a strong nearest-neighbor electron hopping interaction between adjacent ZM states, resulting in a dispersive metallic band. First-principles density functional theory-local density approximation calculations confirm this prediction, and the robust, metallic ZM band of olympicene GNRs is experimentally corroborated by scanning tunneling spectroscopy.
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Affiliation(s)
- Ryan D McCurdy
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Aidan Delgado
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Jingwei Jiang
- Department of Physics, University of California, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Junmian Zhu
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Ethan Chi Ho Wen
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Raymond E Blackwell
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Gregory C Veber
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Shenkai Wang
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Steven G Louie
- Department of Physics, University of California, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Felix R Fischer
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoSciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Bakar Institute of Digital Materials for the Planet, Division of Computing, Data Science, and Society, University of California, Berkeley, California 94720, United States
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42
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Lee J, Ryu H, Park S, Cho M, Choi TL. Living Suzuki-Miyaura Catalyst-Transfer Polymerization for Precision Synthesis of Length-Controlled Armchair Graphene Nanoribbons and Their Block Copolymers. J Am Chem Soc 2023. [PMID: 37376993 DOI: 10.1021/jacs.3c04130] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
The bottom-up synthesis of graphene nanoribbons (GNRs) offers a promising approach for designing atomically precise GNRs with tuneable photophysical properties, but controlling their length remains a challenge. Herein, we report an efficient synthetic protocol for producing length-controlled armchair GNRs (AGNRs) through living Suzuki-Miyaura catalyst-transfer polymerization (SCTP) using RuPhos-Pd catalyst and mild graphitization methods. Initially, SCTP of a dialkynylphenylene monomer was optimized by modifying boronates and halide moieties on the monomers, affording poly(2,5-dialkynyl-p-phenylene) (PDAPP) with controlled molecular weight (Mn up to 29.8k) and narrow dispersity (Đ = 1.14-1.39) in excellent yield (>85%). Subsequently, we successfully obtained N = 5 AGNRs by employing a mild alkyne benzannulation reaction on the PDAPP precursor and confirmed their length retention by size-exclusion chromatography. In addition, photophysical characterization revealed that a molar absorptivity was directly proportional to the length of the AGNR, while its highest occupied molecular orbital (HOMO) energy level remained constant within the given AGNR length. Furthermore, we prepared, for the very first time, N = 5 AGNR block copolymers with widely used donor or acceptor-conjugated polymers by taking advantage of the living SCTP. Finally, we achieved the lateral extension of AGNRs from N = 5 to 11 by oxidative cyclodehydrogenation in solution and confirmed their chemical structure and low band gap by various spectroscopic analyses.
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Affiliation(s)
- Jaeho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Hanseul Ryu
- Department of Materials, ETH Zürich, Zurich 8093, Switzerland
| | - Songyee Park
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Minyoung Cho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae-Lim Choi
- Department of Materials, ETH Zürich, Zurich 8093, Switzerland
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43
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Kuo DMT. Effects of Coulomb Blockade on the Charge Transport through the Topological States of Finite Armchair Graphene Nanoribbons and Heterostructures. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13111757. [PMID: 37299660 DOI: 10.3390/nano13111757] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023]
Abstract
In this study, we investigate the charge transport properties of semiconducting armchair graphene nanoribbons (AGNRs) and heterostructures through their topological states (TSs), with a specific focus on the Coulomb blockade region. Our approach employs a two-site Hubbard model that takes into account both intra- and inter-site Coulomb interactions. Using this model, we calculate the electron thermoelectric coefficients and tunneling currents of serially coupled TSs (SCTSs). In the linear response regime, we analyze the electrical conductance (Ge), Seebeck coefficient (S), and electron thermal conductance (κe) of finite AGNRs. Our results reveal that at low temperatures, the Seebeck coefficient is more sensitive to many-body spectra than electrical conductance. Furthermore, we observe that the optimized S at high temperatures is less sensitive to electron Coulomb interactions than Ge and κe. In the nonlinear response regime, we observe a tunneling current with negative differential conductance through the SCTSs of finite AGNRs. This current is generated by electron inter-site Coulomb interactions rather than intra-site Coulomb interactions. Additionally, we observe current rectification behavior in asymmetrical junction systems of SCTSs of AGNRs. Notably, we also uncover the remarkable current rectification behavior of SCTSs of 9-7-9 AGNR heterostructure in the Pauli spin blockade configuration. Overall, our study provides valuable insights into the charge transport properties of TSs in finite AGNRs and heterostructures. We emphasize the importance of considering electron-electron interactions in understanding the behavior of these materials.
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Affiliation(s)
- David M T Kuo
- Department of Electrical Engineering, National Central University, Chungli 320, Taiwan, China
- Department of Physics, National Central University, Chungli 320, Taiwan, China
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44
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Xing GY, Zhu YC, Li DY, Liu PN. On-Surface Cross-Coupling Reactions. J Phys Chem Lett 2023; 14:4462-4470. [PMID: 37154541 DOI: 10.1021/acs.jpclett.3c00344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
On-surface synthesis, as a bottom-up synthetic method, has been proven to be a powerful tool for atomically precise fabrication of low-dimensional carbon nanomaterials over the past 15 years. This method relies on covalent coupling reactions that occur on solid substrates such as metal or metal oxide surfaces under ultra-high-vacuum conditions, and the achievements with this method have greatly enriched fundamental science and technology. However, due to the complicated reactivity of organic groups, distinct diffusion of reactants and intermediates, and irreversibility of covalent bonds, achieving the high selectivity of covalent coupling reactions on surfaces remains a great challenge. As a result, only a few on-surface covalent coupling reactions, mainly involving dehalogenation and dehydrogenation homocoupling, are frequently used in the synthesis of low-dimensional carbon nanosystems. In this Perspective, we focus on the development and synthetic applications of on-surface cross-coupling reactions, mainly Ullmann, Sonogashira, Heck, and divergent cross-coupling reactions.
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Affiliation(s)
- Guang-Yan Xing
- Shanghai Key Laboratory of Functional Materials Chemistry, Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Ya-Cheng Zhu
- Shanghai Key Laboratory of Functional Materials Chemistry, Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Deng-Yuan Li
- Shanghai Key Laboratory of Functional Materials Chemistry, Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Pei-Nian Liu
- Shanghai Key Laboratory of Functional Materials Chemistry, Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
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45
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Kuo DMT. Effects of metallic electrodes on the thermoelectric properties of zigzag graphene nanoribbons with periodic vacancies. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:305301. [PMID: 37068484 DOI: 10.1088/1361-648x/accdac] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 04/17/2023] [Indexed: 06/19/2023]
Abstract
We theoretically analyze the thermoelectric properties of graphene quantum dot arrays (GQDAs) with line- or surface-contacted metal electrodes. Such GQDAs are realized as zigzag graphene nanoribbons (ZGNRs) with periodic vacancies. Gaps and minibands are formed in these GQDAs, which can have metallic and semiconducting phases. The electronic states of the first conduction (valence) miniband with nonlinear dispersion may have long coherent lengths along the zigzag edge direction. With line-contacted metal electrodes, the GQDAs have the characteristics of serially coupled quantum dots (SCQDs) if the armchair edge atoms of the ZGNRs are coupled to the electrodes. By contrast, the GQDAs have the characteristics of parallel quantum dots if the zigzag edge atoms are coupled to the electrodes. The maximum thermoelectric power factors of SCQDs with line-contacted electrodes of Cu, Au, Pt, Pd, or Ti at room temperature were similar or greater than 0.186 nW K-1; their figures of merit were greater than three. GQDAs with line-contacted metal electrodes have much better thermoelectric performance than surface contacted metal electrodes.
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Affiliation(s)
- David M T Kuo
- Department of Electrical Engineering and Department of Physics, National Central University, Chungli 320, Taiwan
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46
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Ma C, Wang J, Ma H, Yin R, Zhao XJ, Du H, Meng X, Ke Y, Hu W, Li B, Tan S, Tan YZ, Yang J, Wang B. Remote-Triggered Domino-like Cyclodehydrogenation in Second-Layer Topological Graphene Nanoribbons. J Am Chem Soc 2023; 145:10126-10135. [PMID: 37097709 DOI: 10.1021/jacs.3c00563] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
Cyclodehydrogenation reactions in the on-surface synthesis of graphene nanoribbons (GNRs) usually involve a series of Csp2-Csp2 and/or Csp2-Csp3 couplings and just happen on uncovered metal or metal oxide surfaces. It is still a big challenge to extend the growth of second-layer GNRs in the absence of necessary catalytic sites. Here, we demonstrate the direct growth of topologically nontrivial GNRs via multistep Csp2-Csp2 and Csp2-Csp3 couplings in the second layer by annealing designed bowtie-shaped precursor molecules over one monolayer on the Au(111) surface. After annealing at 700 K, most of the polymerized chains that appear in the second layer covalently link to the first-layer GNRs that have partially undergone graphitization. Following annealing at 780 K, the second-layer GNRs are formed and linked to the first-layer GNRs. Benefiting from the minimized local steric hindrance of the precursors, we suggest that the second-layer GNRs undergo domino-like cyclodehydrogenation reactions that are remotely triggered at the link. We confirm the quasi-freestanding behaviors in the second-layer GNRs by measuring the quasiparticle energy gap of topological bands and the tunable Kondo resonance from topological end spins using scanning tunneling microscopy/spectroscopy combined with first-principles calculations. Our findings pave the avenue to diverse multilayer graphene nanostructures with designer quantum spins and topological states for quantum information science.
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Affiliation(s)
- Chuanxu Ma
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Jufeng Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Huanhuan Ma
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Ruoting Yin
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xin-Jing Zhao
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Hongjian Du
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Xinyong Meng
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yifan Ke
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Wei Hu
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Bin Li
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Shijing Tan
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Yuan-Zhi Tan
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Jinlong Yang
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Bing Wang
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
- New Cornerstone Science Laboratory, Shenzhen 518054, China
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47
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Liu JC, Pawlak R, Wang X, Chen H, D’Astolfo P, Drechsel C, Zhou P, Häner R, Decurtins S, Aschauer U, Liu SX, Wulfhekel W, Meyer E. Proximity-Induced Superconductivity in Atomically Precise Nanographene on Ag/Nb(110). ACS MATERIALS LETTERS 2023; 5:1083-1090. [PMID: 37034384 PMCID: PMC10074385 DOI: 10.1021/acsmaterialslett.2c00955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 02/16/2023] [Indexed: 06/19/2023]
Abstract
Obtaining a robust superconducting state in atomically precise nanographene (NG) structures by proximity to a superconductor could foster the discovery of topological superconductivity in graphene. On-surface synthesis of such NGs has been achieved on noble metals and metal oxides; however, it is still absent on superconductors. Here, we present a synthetic method to induce superconductivity of polymeric chains and NGs adsorbed on the superconducting Nb(110) substrate covered by thin Ag films. Using atomic force microscopy at low temperature, we characterize the chemical structure of each subproduct formed on the superconducting Ag layer. Scanning tunneling spectroscopy further allows us to elucidate the electronic properties of these nanostructures, which consistently show a superconducting gap.
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Affiliation(s)
- Jung-Ching Liu
- Department
of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Rémy Pawlak
- Department
of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Xing Wang
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Hongyan Chen
- Physikalisches
Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, Karlsruhe 76131, Germany
| | - Philipp D’Astolfo
- Department
of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Carl Drechsel
- Department
of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Ping Zhou
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Robert Häner
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Silvio Decurtins
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Ulrich Aschauer
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Shi-Xia Liu
- Department
of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, Bern 3012, Switzerland
| | - Wulf Wulfhekel
- Physikalisches
Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, Karlsruhe 76131, Germany
| | - Ernst Meyer
- Department
of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
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48
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Cassiano TDSA, Júnior LAR, Silva GME, Neto PHDO. Regulating Polaron Transport Regime via Heterojunction Engineering in Cove‐Type Graphene Nanoribbons. ADVANCED THEORY AND SIMULATIONS 2023. [DOI: 10.1002/adts.202200877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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49
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Ma Y, Sugawara K, Ishigaki Y, Sun K, Suzuki T, Kawai S. Strain-Sensitive On-Surface Ladderization by Non-Dehydrogenative Heterocyclization. Chemistry 2023; 29:e202203622. [PMID: 36539358 DOI: 10.1002/chem.202203622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022]
Abstract
On-surface cyclodehydrogenation recently became an important reaction to planarize π-conjugated molecules and oligomers. However, the high-activation barrier to cleave the C-H bond often requires high-temperature annealing, consequently restricting structures of precursor molecules and/or leading to random fusion at their edges. Here, we present a synthesis of pyrrolopyrrole-bridged ladder oligomers from 11,11,12,12-tetrabromo-1,4,5,8-tetraaza-9,10-anthraquinodimethane molecules on Ag(111) with bond-resolved scanning tunnelling microscopy. This non-dehydrogenative cyclization between pyrazine and ethynylene/cumulene groups has a low-activation barrier for forming intermediary dimeric oligomer containing dipyrazinopyrrolopyrrolopyrazine units, thus giving new insight into the strain-sensitive in ladder-oligomer formation.
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Affiliation(s)
- Yujing Ma
- Research Center for Advanced Measurement and Characterization, National Institute for Materials Science, Sengen 1-2-1, Tsukuba, Ibaraki, 305-0047, Japan
| | - Kazuma Sugawara
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Yusuke Ishigaki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Kewei Sun
- Research Center for Advanced Measurement and Characterization, National Institute for Materials Science, Sengen 1-2-1, Tsukuba, Ibaraki, 305-0047, Japan
| | - Takanori Suzuki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Shigeki Kawai
- Research Center for Advanced Measurement and Characterization, National Institute for Materials Science, Sengen 1-2-1, Tsukuba, Ibaraki, 305-0047, Japan.,Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, 305-8571, Japan
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50
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Wang T, Fan Q, Zhu J. Steering On-Surface Reactions by Kinetic and Thermodynamic Strategies. J Phys Chem Lett 2023; 14:2251-2262. [PMID: 36821589 DOI: 10.1021/acs.jpclett.3c00001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
On-surface synthesis has emerged as a powerful tool to fabricate various functional low-dimensional nanostructures with atomic precision, thus becoming a promising platform for the preparation of next-generation semiconductive, magnetic, and topological nanodevices. With the aid of scanning tunneling microscopy/spectroscopy and noncontact atomic force microscopy, both the chemical structures and physical properties of the obtained products can be well characterized. A major challenge in this field is how to efficiently steer reaction pathways and improve the yield/quality of products. To address this problem, in recent years various kinetic and thermodynamic strategies have been successfully employed to control on-surface reactions. In this Perspective, we discuss these strategies in view of basic reaction steps on surfaces, including molecular adsorption, diffusion, and reaction. We hope this Perspective will help readers to deepen the understanding of the mechanisms of on-surface reactions and rationally design reaction procedures for the fabrication of high-quality functional nanomaterials on surfaces.
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Affiliation(s)
- Tao Wang
- Department of Pharmacy, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, and National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China
- Donostia International Physics Center, San Sebastián 20018, Spain
| | - Qitang Fan
- Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Junfa Zhu
- Department of Pharmacy, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, and National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China
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