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Xie G, Liu X, Guo B, Tan T, Gong JR. Porous 2D Catalyst Covers Improve Photoelectrochemical Water-Oxidation Performance. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2211008. [PMID: 37120723 DOI: 10.1002/adma.202211008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/26/2023] [Indexed: 06/19/2023]
Abstract
Confined catalysis under the cover of 2D materials has emerged as a promising approach for achieving highly effective catalysts in various essential reactions. In this work, a porous cover structure is designed to boost the interfacial charge and mass transfer kinetics of 2D-covered catalysts. The improvement in catalytic performance is confirmed by the photoelectrochemical oxidation evolution reaction (OER) on a photoanode based on an n-Si substrate modified with a NiOx thin-film model electrocatalyst covered with a porous graphene (pGr) monolayer. Experimental results demonstrate that the pGr cover enhances the OER kinetics by balancing the charge and mass transfer at the photoanode and electrolyte interface compared to the intrinsic graphene cover and cover-free control samples. Theoretical investigations further corroborate that the pore edges of the pGr cover boost the intrinsic catalytic activity of active sites on NiOx by reducing the reaction overpotential. Furthermore, the optimized pores, which can be easily controlled by plasma bombardment, allow oxygen molecules produced in the OER to pass through without peeling off the pGr cover, thus ensuring the structural stability of the catalyst. This study highlights the significant role of the porous cover structure in 2D-covered catalysts and provides new insight into the design of high-performance catalysts.
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Affiliation(s)
- Guancai Xie
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, CAS Key Laboratory for Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Xiaolong Liu
- Laboratory of Theoretical and Computational Nanoscience, CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Beidou Guo
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, CAS Key Laboratory for Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Ting Tan
- Laboratory of Theoretical and Computational Nanoscience, CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology, Beijing, 100190, China
- University of CAS, Beijing, 100049, China
| | - Jian Ru Gong
- Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience, CAS Key Laboratory for Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, China
- University of CAS, Beijing, 100049, China
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2
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Tian H, Yao Z, Li Z, Guo J, Liu L. Unlocking More Potentials in Two-Dimensional Space: Disorder Engineering in Two-Dimensional Amorphous Carbon. ACS NANO 2023; 17:24468-24478. [PMID: 38015075 DOI: 10.1021/acsnano.3c09593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The theory of the nature of glass has been described as the deepest but unsolved problem in solid state theory. The fundamental understanding of the structural characteristics of glassy materials and disorder-property correspondence remains incomplete due to difficulties in fully characterizing disordered structures in three-dimensional materials. Recently, two-dimensional amorphous materials were treated as an atomic-level playground to uncover previously unknown structure-property relationships in vitreous materials. Here, we summarize recent research on one prototypical material, two-dimensional amorphous carbon, including atomic structural characterizations, controllable synthesis, exotic properties, and application potentials. Fundamental discrepancies only induced by the amorphous nature, when compared with crystalline materials, will be highlighted. Finally, we discuss the restricted definition of two-dimensional amorphous carbon, existing challenges, and future research directions.
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Affiliation(s)
- Huifeng Tian
- School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Zhixin Yao
- School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, People's Republic of China
| | - Zhenjiang Li
- School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Junjie Guo
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, People's Republic of China
| | - Lei Liu
- School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China
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3
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Yerlanuly Y, Zhumadilov RY, Danko IV, Janseitov DM, Nemkayeva RR, Kireyev AV, Arystan AB, Akhtanova G, Vollbrecht J, Schopp N, Nurmukhanbetova A, Ramazanov TS, Jumabekov AN, Oreshkin PA, Zholdybayev TK, Gabdullin MT, Brus VV. Effect of Electron and Proton Irradiation on Structural and Electronic Properties of Carbon Nanowalls. ACS OMEGA 2022; 7:48467-48475. [PMID: 36591155 PMCID: PMC9798766 DOI: 10.1021/acsomega.2c06735] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
In this work, a complex experimental study of the effect of electron and proton ionizing radiation on the properties of carbon nanowalls (CNWs) is carried out using various state-of-the-art materials characterization techniques. CNW layers on quartz substrates were exposed to 5 MeV electron and 1.8 MeV proton irradiation with accumulated fluences of 7 × 1013 e/cm2 and 1012 p/cm2, respectively. It is found that depending on the type of irradiation (electron or proton), the morphology and structural properties of CNWs change; in particular, the wall density decreases, and the sp2 hybridization component increases. The morphological and structural changes in turn lead to changes in the electronic, optical, and electrical characteristics of the material, in particular, change in the work function, improvement in optical transmission, an increase in the surface resistance, and a decrease in the specific conductivity of the CNW films. Lastly, this study highlights the potential of CNWs as nanostructured functional materials for novel high-performance radiation-resistant electronic and optoelectronic devices.
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Affiliation(s)
- Yerassyl Yerlanuly
- Kazakh-British
Technical University, Almaty 050000, Kazakhstan
- Al-Farabi
Kazakh National University, Almaty 050040, Kazakhstan
- Department
of Physics, Nazarbayev University, Nur-Sultan City 010000, Kazakhstan
| | - Rakhymzhan Ye Zhumadilov
- Kazakh-British
Technical University, Almaty 050000, Kazakhstan
- Al-Farabi
Kazakh National University, Almaty 050040, Kazakhstan
| | - Igor V. Danko
- Institute
of Nuclear Physics, Almaty 050032, Kazakhstan
| | | | - Renata R. Nemkayeva
- Kazakh-British
Technical University, Almaty 050000, Kazakhstan
- Al-Farabi
Kazakh National University, Almaty 050040, Kazakhstan
| | | | | | - Gulnur Akhtanova
- Department
of Physics, Nazarbayev University, Nur-Sultan City 010000, Kazakhstan
| | | | - Nora Schopp
- University
of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Aliya Nurmukhanbetova
- Energetic
Cosmos Laboratory, Nazarbayev University, Nur-Sultan City 010000, Kazakhstan
| | | | - Askhat N. Jumabekov
- Department
of Physics, Nazarbayev University, Nur-Sultan City 010000, Kazakhstan
| | | | | | | | - Viktor V. Brus
- Department
of Physics, Nazarbayev University, Nur-Sultan City 010000, Kazakhstan
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4
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Shiryaev AA, Trigub AL, Voronina EN, Kvashnina KO, Bukhovets VL. Behavior of implanted Xe, Kr and Ar in nanodiamonds and thin graphene stacks: experiment and modeling. Phys Chem Chem Phys 2021; 23:21729-21737. [PMID: 34550143 DOI: 10.1039/d1cp02600c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Implantation and subsequent behaviour of heavy noble gases (Ar, Kr, and Xe) in few-layer graphene sheets and in nanodiamonds are studied both using computational methods and experimentally using X-ray absorption spectroscopy. X-ray absorption spectroscopy provides substantial support for Xe-vacancy (Xe-V) defects as main sites for Xe in nanodiamonds. It is shown that noble gases in thin graphene stacks distort the layers, forming bulges. The energy of an ion placed in between flat graphene sheets is notably lower than that in domains with high curvature. However, if the ion is trapped in the curved domain, considerable additional energy is required to displace it. This phenomenon is likely responsible for strong binding of noble gases implanted into disordered carbonaceous phase in meteorites (the Q-component).
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Affiliation(s)
- Andrey A Shiryaev
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky pr. 31 korp. 4, 119071, Moscow, Russia.
| | - Alexander L Trigub
- National Research Center «Kurchatov Institute», Moscow, Russia.,Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | | | - Kristina O Kvashnina
- The Rossendorf Beamline at ESRF - The European Synchrotron, CS40220, 38043 Grenoble Cedex 9, France.,Helmholtz Zentrum Dresden-Rossendorf (HZDR), Institute of Resource Ecology, PO Box 510119, 01314 Dresden, Germany.,Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Valentin L Bukhovets
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninsky pr. 31 korp. 4, 119071, Moscow, Russia.
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5
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Fujisawa K, Carvalho BR, Zhang T, Perea-López N, Lin Z, Carozo V, Ramos SLLM, Kahn E, Bolotsky A, Liu H, Elías AL, Terrones M. Quantification and Healing of Defects in Atomically Thin Molybdenum Disulfide: Beyond the Controlled Creation of Atomic Defects. ACS NANO 2021; 15:9658-9669. [PMID: 33754710 DOI: 10.1021/acsnano.0c10897] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Atomically thin 2D materials provide an opportunity to investigate the atomic-scale details of defects introduced by particle irradiation. Once the atomic configuration of defects and their spatial distribution are revealed, the details of the mesoscopic phenomena can be unveiled. In this work, we created atomically small defects by controlled irradiation of gallium ions with doses ranging from 4.94 × 1012 to 4.00 × 1014 ions/cm2 on monolayer molybdenum disulfide (MoS2) crystals. The optical signatures of defects, such as the evolution of defect-activated LA-bands and a broadening of the first-order (E' and A'1) modes, can be studied by Raman spectroscopy. High-resolution scanning transmission electron microscopy (HR-STEM) analysis revealed that most defects are vacancies of few-molybdenum atoms with surrounding sulfur atoms (VxMo+yS) at a low ion dose. When increasing the ion dose, the atomic vacancies merge and form nanometer-sized holes. Utilizing HR-STEM and image analysis, we propose the estimation of the finite crystal length (Lfc) via the careful quantification of 0D defects in 2D systems through the formula Lfc = 4.41/ηion, where ηion corresponds to the ion dose. Combining HR-STEM and Raman spectroscopy, the formula to calculate Lfc from Raman features, I(LA)/I(A'1) = 5.09/Lfc2, is obtained. We have also demonstrated an effective route to healing the ion irradiation-induced atomic vacancies by annealing defective MoS2 in a hydrogen disulfide (H2S) atmosphere. The H2S annealing improved the crystal quality of MoS2 with Lfc greater than the calculated size of the A exciton wave function, which leads to a partial recovery of the photoluminescence signal after its quenching by ion irradiation.
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Affiliation(s)
- Kazunori Fujisawa
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Research Initiative for Supra Materials, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
| | - Bruno R Carvalho
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Departamento de Física, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59078-970, Brazil
| | - Tianyi Zhang
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Néstor Perea-López
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Zhong Lin
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Victor Carozo
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Physics, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro 22451900, Brazil
| | - Sérgio L L M Ramos
- Centro de Tecnologia em Nanomateriais (CT Nano), Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 30161-970, Brazil
| | - Ethan Kahn
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Adam Bolotsky
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - He Liu
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ana Laura Elías
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Physics, Binghamton University, Binghamton, New York 13902, United States
| | - Mauricio Terrones
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Research Initiative for Supra Materials, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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6
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Deng Y, Wang G, Qiu Y, He D, Lin J, He J. Nano-patterning of a monolayer molybdenum disulfide with sub-nanometer helium ion beam: considering its shape, size and damage. NANOTECHNOLOGY 2020; 31:345302. [PMID: 32375133 DOI: 10.1088/1361-6528/ab90b5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We have studied nano-patterning of a two-dimensional (2D) material with an ultrafine helium ion beam considering shape-, size- and damage-control. The study reveals that the crystalline structure plays an important role in shape-control. Instead of commonly circular-shaped nanopores, spot irradiation onto a single layer of molybdenum disulfide (MoS2) gives rise to a rhombus-shaped nanopore, which is well explained by the sub-rhombus crystalline structure of MoS2. Helium ion beams also show promising capability to precisely control size using a delivered dose. However, the size of the nanopores is not linear with the delivered dose, due to the Gaussian distributed intensity profile of the helium ion beam. The intensity profiles are further estimated by considering aperture size, those results could be taken as a significant reference for size-control. In addition, we clarify that most of the damage is a result of re-deposition, thus controlling re-deposition might be a useful way to alleviate the damage.
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Affiliation(s)
- Yunsheng Deng
- Pico Center and SUSTech Core Research Facilities, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China
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7
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Coquand O, Essafi K, Kownacki JP, Mouhanna D. Universal behaviors in the wrinkling transition of disordered membranes. Phys Rev E 2020; 101:042602. [PMID: 32422798 DOI: 10.1103/physreve.101.042602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 02/24/2020] [Indexed: 06/11/2023]
Abstract
The wrinkling transition experimentally identified by Mutz et al. [Phys. Rev. Lett. 67, 923 (1991)PRLTAO0031-900710.1103/PhysRevLett.67.923] and then thoroughly studied by Chaieb et al. [Phys. Rev. Lett. 96, 078101 (2006)]PRLTAO0031-900710.1103/PhysRevLett.96.078101 in partially polymerized lipid membranes is reconsidered. One shows that the features associated with this transition, notably the various scaling behaviors of the height-height correlation functions that have been observed, are qualitatively and quantitatively well described by a recent nonperturbative renormalization group approach to quenched disordered membranes by Coquand et al. [Phys. Rev E 97, 030102(R) (2018)]2470-004510.1103/PhysRevE.97.030102. As these behaviors are associated with fixed points of renormalization group transformations they are universal and should also be observed in, e.g., defective graphene and graphene-like materials.
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Affiliation(s)
- O Coquand
- Sorbonne Université, CNRS, Laboratoire de Physique Théorique de la Matière Condensée, LPTMC, F-75005 Paris, France
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, Linder Höhe, 51147 Köln, Germany
| | - K Essafi
- Sorbonne Université, CNRS, Laboratoire de Physique Théorique de la Matière Condensée, LPTMC, F-75005 Paris, France
| | - J-P Kownacki
- LPTM, CNRS UMR 8089-Université de Cergy-Pontoise, 2 avenue Adolphe Chauvin, 95302 Cergy-Pontoise Cedex, France
| | - D Mouhanna
- Sorbonne Université, CNRS, Laboratoire de Physique Théorique de la Matière Condensée, LPTMC, F-75005 Paris, France
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8
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Feng Y, Wu J, Chi Q, Li W, Yu Y, Fei W. Defects and Aliovalent Doping Engineering in Electroceramics. Chem Rev 2020; 120:1710-1787. [DOI: 10.1021/acs.chemrev.9b00507] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Yu Feng
- Key Laboratory of Engineering Dielectrics and Its Application, Ministry of Education, Harbin University of Science and Technology, Harbin 150080, P. R. China
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, P. R. China
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Jiagang Wu
- Department of Materials Science, Sichuan University, Chengdu 610064, P. R. China
| | - Qingguo Chi
- Key Laboratory of Engineering Dielectrics and Its Application, Ministry of Education, Harbin University of Science and Technology, Harbin 150080, P. R. China
| | - Weili Li
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Yang Yu
- Key Laboratory of Engineering Dielectrics and Its Application, Ministry of Education, Harbin University of Science and Technology, Harbin 150080, P. R. China
| | - Weidong Fei
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, P. R. China
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9
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Cai Y, Chen S, Gao J, Zhang G, Zhang YW. Evolution of intrinsic vacancies and prolonged lifetimes of vacancy clusters in black phosphorene. NANOSCALE 2019; 11:20987-20995. [PMID: 31660564 DOI: 10.1039/c9nr06608j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Due to the relatively low formation energies and highly mobile characteristics of atomic vacancies in phosphorene, understanding their evolution becomes crucial for its structural integrity, chemical activities and applications. Herein, by combining first-principles calculations and kinetic Monte Carlo simulation, we investigate the time evolution and formation of atomic vacancy clusters from isolated monovacancies (MVs), aiming to uncover the mechanisms of diffusion, annihilation, and reaction of these atomic vacancies. We find that while isolated MVs possess a highly mobile characteristic, they react and form MV pairs which possess much lower mobility and high stability under ambient conditions. We also show that the disappearance of MVs at the edge is quite slow due to the relatively high energy barrier, and as a result, around 80% of MVs remain even after two years under ambient conditions. Our findings on one hand provide useful information for the structural repairing of phosphorene through chemical functionalization of these vacancy clusters, and on the other hand, suggest that these rather stable vacancy clusters may be used as activated catalysts.
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Affiliation(s)
- Yongqing Cai
- Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Taipa, Macau, China and Institute of High Performance Computing, A*STAR, Singapore 138732.
| | - Shuai Chen
- Institute of High Performance Computing, A*STAR, Singapore 138732.
| | - Junfeng Gao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian, 116024, China
| | - Gang Zhang
- Institute of High Performance Computing, A*STAR, Singapore 138732.
| | - Yong-Wei Zhang
- Institute of High Performance Computing, A*STAR, Singapore 138732.
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10
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Chaturvedi P, Vlassiouk IV, Cullen DA, Rondinone AJ, Lavrik NV, Smirnov SN. Ionic Conductance through Graphene: Assessing Its Applicability as a Proton Selective Membrane. ACS NANO 2019; 13:12109-12119. [PMID: 31592639 DOI: 10.1021/acsnano.9b06505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Inspired by recent reports on possible proton conductance through graphene, we have investigated the behavior of pristine graphene and defect engineered graphene membranes for ionic conductance and selectivity with the goal of evaluating a possibility of its application as a proton selective membrane. The averaged conductance for pristine chemical vapor deposited (CVD) graphene at pH1 is ∼4 mS/cm2 but varies strongly due to contributions from the unavoidable defects in our CVD graphene. From the variations in the conductance with electrolyte strength and pH, we can conclude that pristine graphene is fairly selective and the conductance is mainly due to protons. Engineering of the defects with ion beam (He+, Ga+) irradiation and plasma (N2 and H2) treatment showed improved areal conductance with high proton selectivity mostly for He-ion beam and H2 plasma treatments, which agrees with primarily vacancy-free type of defects produced in these cases confirmed by Raman analysis.
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Affiliation(s)
- Pavan Chaturvedi
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
| | - Ivan V Vlassiouk
- Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - David A Cullen
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Adam J Rondinone
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Nickolay V Lavrik
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Sergei N Smirnov
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
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11
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Evidence of a two-dimensional glass transition in graphene: Insights from molecular simulations. Sci Rep 2019; 9:4517. [PMID: 30872750 PMCID: PMC6418284 DOI: 10.1038/s41598-019-41231-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 03/05/2019] [Indexed: 11/23/2022] Open
Abstract
Liquids exhibit a sudden increase in viscosity when cooled fast enough, avoiding thermodynamically predicted route of crystallization. This phenomenon, known as glass transition, leads to the formation of non-periodic structures known as glasses. Extensive studies have been conducted on model materials to understand glass transition in two dimensions. However, despite the synthesis of disordered/amorphous single-atom thick structures of carbon, little attention has been given to glass transition in realistic two-dimensional materials such as graphene. Herein, using molecular dynamics simulation, we demonstrate the existence of glass transition in graphene leading to a realistic two-dimensional glassy structure, namely glassy graphene. We show that the resulting glassy structure exhibits excellent agreement with experimentally realized disordered graphene. Interestingly, this glassy graphene exhibits a wrinkled but stable structure, with reduced thermal vibration in comparison to its crystalline counterpart. We suggest that the topological disorder induced by glass transition governs the unique properties of this structure.
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12
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Valerius P, Herman A, Michely T. Suppression of wrinkle formation in graphene on Ir(111) by high-temperature, low-energy ion irradiation. NANOTECHNOLOGY 2019; 30:085304. [PMID: 30523818 DOI: 10.1088/1361-6528/aaf534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Graphene on Ir(111) is irradiated with small fluences of 500 eV He ions at temperatures close to its chemical vapor deposition growth temperature. The ion irradiation experiments explore whether it is possible to suppress the formation of wrinkles in Gr during growth. It is found that the release of thermal mismatch strain by wrinkle formation can be entirely suppressed for an irradiation temperature of 880 °C. A model for the ion beam induced suppression of wrinkle formation in supported Gr is presented, and underpinned by experiments varying the irradiation temperature or involving intercalation subsequent to irradiation.
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13
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Study of Implantation Defects in CVD Graphene by Optical and Electrical Methods. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9030544] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A Chemical Vapor Deposition graphene monolayer grown on 6H–SiC (0001) substrates was used for implantation experiments. The graphene samples were irradiated by He+ and N+ ions. The Raman spectra and electrical transport parameters were measured as a function of increasing implantation fluence. The defect concentration was determined from intensity ratio of the Raman D and G peaks, while the carrier’s concentration was determined from the relations between G and 2D Raman modes energies. It was found that the number of defects generated by one ion is 0.0025 and 0.045 and the mean defect radius about 1.5 and 1.34 nm for He+ and N+, respectively. Hole concentration and mobility were determined from van der Pauw measurements. It was found that mobility decreases nearly by three orders of magnitude with increase of defect concentration. The inverse of mobility versus defect concentration is a linear function, which indicates that the main scattering mechanism is related to defects generated by ion implantation. The slope of inverse mobility versus defect concentration provides the value of defect radius responsible for scattering carriers at about 0.75 nm. This estimated defect radius indicates that the scattering centres most likely consist of reconstructed divacancies or larger vacancy complexes.
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14
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Eswara S, Audinot JN, El Adib B, Guennou M, Wirtz T, Philipp P. Defect formation in multiwalled carbon nanotubes under low-energy He and Ne ion irradiation. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:1951-1963. [PMID: 30116687 PMCID: PMC6071685 DOI: 10.3762/bjnano.9.186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/27/2018] [Indexed: 06/01/2023]
Abstract
The mechanical, structural, electronic and magnetic properties of carbon nanotubes can be modified by electron or ion irradiation. In this work we used 25 keV He+ and Ne+ ion irradiation to study the influence of fluence and sample thickness on the irradiation-induced damage of multiwalled carbon nanotubes (MWCNTs). The irradiated areas have been characterised by correlative Raman spectroscopy and TEM imaging. In order to preclude the Raman contribution coming from the amorphous carbon support of typical TEM grids, a new methodology involving Raman inactive Au TEM grids was developed. The experimental results have been compared to SDTRIMSP simulations. Due to the small thickness of the MWCNTs, sputtering has been observed for the top and bottom side of the samples. Depending on thickness and ion species, the sputter yield is significantly higher for the bottom than the top side. For He+ and Ne+ irradiation, damage formation evolves differently, with a change in the trend of the ratio of D to G peak in the Raman spectra being observed for He+ but not for Ne+. This can be attributed to differences in stopping power and sputter behaviour.
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Affiliation(s)
- Santhana Eswara
- Advanced Instrumentation for Ion Nano-Analytics (AINA), MRT Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, L-4422 Belvaux, Luxembourg
| | - Jean-Nicolas Audinot
- Advanced Instrumentation for Ion Nano-Analytics (AINA), MRT Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, L-4422 Belvaux, Luxembourg
| | - Brahime El Adib
- Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 41 rue du Brill, L-4422 Belvaux, Luxembourg
| | - Maël Guennou
- Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 41 rue du Brill, L-4422 Belvaux, Luxembourg
| | - Tom Wirtz
- Advanced Instrumentation for Ion Nano-Analytics (AINA), MRT Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, L-4422 Belvaux, Luxembourg
| | - Patrick Philipp
- Advanced Instrumentation for Ion Nano-Analytics (AINA), MRT Department, Luxembourg Institute of Science and Technology (LIST), 41 rue du Brill, L-4422 Belvaux, Luxembourg
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15
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Joo WJ, Lee JH, Jang Y, Kang SG, Kwon YN, Chung J, Lee S, Kim C, Kim TH, Yang CW, Kim UJ, Choi BL, Whang D, Hwang SW. Realization of continuous Zachariasen carbon monolayer. SCIENCE ADVANCES 2017; 3:e1601821. [PMID: 28246635 PMCID: PMC5302873 DOI: 10.1126/sciadv.1601821] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/22/2016] [Indexed: 05/14/2023]
Abstract
Rapid progress in two-dimensional (2D) crystalline materials has recently enabled a range of device possibilities. These possibilities may be further expanded through the development of advanced 2D glass materials. Zachariasen carbon monolayer, a novel amorphous 2D carbon allotrope, was successfully synthesized on germanium surface. The one-atom-thick continuous amorphous layer, in which the in-plane carbon network was fully sp2-hybridized, was achieved at high temperatures (>900°C) and a controlled growth rate. We verified that the charge carriers within the Zachariasen carbon monolayer are strongly localized to display Anderson insulating behavior and a large negative magnetoresistance. This new 2D glass also exhibited a unique ability as an atom-thick interface layer, allowing the deposition of an atomically flat dielectric film. It can be adopted in conventional semiconductor and display processing or used in the fabrication of flexible devices consisting of thin inorganic layers.
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Affiliation(s)
- Won-Jae Joo
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Jae-Hyun Lee
- SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 16419, Korea
- National Graphene Institute, University of Manchester, Manchester M13 9PL, U.K
| | - Yamujin Jang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Seog-Gyun Kang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Young-Nam Kwon
- Analytical Science Group, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Jaegwan Chung
- Analytical Science Group, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Sangyeob Lee
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Changhyun Kim
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Tae-Hoon Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Cheol-Woong Yang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
| | - Un Jeong Kim
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Byoung Lyong Choi
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
| | - Dongmok Whang
- SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 16419, Korea
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea
- Corresponding author. (D.W.); (S.-W.H.)
| | - Sung-Woo Hwang
- Device Laboratory, Samsung Advanced Institute of Technology, Suwon 16674, Korea
- Corresponding author. (D.W.); (S.-W.H.)
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16
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Yoon K, Rahnamoun A, Swett JL, Iberi V, Cullen DA, Vlassiouk IV, Belianinov A, Jesse S, Sang X, Ovchinnikova OS, Rondinone AJ, Unocic RR, van Duin ACT. Atomistic-Scale Simulations of Defect Formation in Graphene under Noble Gas Ion Irradiation. ACS NANO 2016; 10:8376-8384. [PMID: 27532882 DOI: 10.1021/acsnano.6b03036] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Despite the frequent use of noble gas ion irradiation of graphene, the atomistic-scale details, including the effects of dose, energy, and ion bombardment species on defect formation, and the associated dynamic processes involved in the irradiations and subsequent relaxation have not yet been thoroughly studied. Here, we simulated the irradiation of graphene with noble gas ions and the subsequent effects of annealing. Lattice defects, including nanopores, were generated after the annealing of the irradiated graphene, which was the result of structural relaxation that allowed the vacancy-type defects to coalesce into a larger defect. Larger nanopores were generated by irradiation with a series of heavier noble gas ions, due to a larger collision cross section that led to more detrimental effects in the graphene, and by a higher ion dose that increased the chance of displacing the carbon atoms from graphene. Overall trends in the evolution of defects with respect to a dose, as well as the defect characteristics, were in good agreement with experimental results. Additionally, the statistics in the defect types generated by different irradiating ions suggested that the most frequently observed defect types were Stone-Thrower-Wales (STW) defects for He(+) irradiation and monovacancy (MV) defects for all other ion irradiations.
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Affiliation(s)
- Kichul Yoon
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Ali Rahnamoun
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Jacob L Swett
- Advanced Technology Center, Lockheed Martin Space Systems Company , Palo Alto, California 94304, United States
| | - Vighter Iberi
- Department of Materials Science and Engineering, University of Tennessee , Knoxville, Tennessee 37996, United States
| | | | | | | | | | | | | | | | | | - Adri C T van Duin
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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17
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Srivastava PK, Yadav P, Ghosh S. Non-oxidative, controlled exfoliation of graphite in aqueous medium. NANOSCALE 2016; 8:15702-15711. [PMID: 27523721 DOI: 10.1039/c6nr04244a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a simple, non-oxidative and controlled method to synthesize graphene monolayers by exfoliation in water from different solid carbon sources, such as highly ordered pyrolytic graphite and low density graphite. Any water based method is highly desirable due to several attractive features, such as environmental friendliness, low cost and wide compatibility with other water based processes. We show that thin graphene layers can be exfoliated controllably and reproducibly by varying different parameters during exfoliation in aqueous medium. It has been possible to obtain high quality graphene monolayers with a yield of ∼2.45 wt%, which can be increased up to 16.6 wt% by recycling the sediments. Field effect transistors based on exfoliated graphene monolayers have shown n-type doping and a high carrier mobility of 4500 cm(2) V(-1) s(-1) at room temperature and ∼20 000 cm(2) V(-1) s(-1) at low temperature. Density functional calculations corroborate the infrared spectroscopic results and also indicate that the charge transfer preferentially occurs from water molecules to the graphene sheets resulting in n-type doping. We anticipate that exfoliation of high quality graphene layers in aqueous medium would open up a pathway for various graphene based electronic and biological applications.
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Affiliation(s)
- Pawan Kumar Srivastava
- Electronic Materials and Device Laboratory School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
| | - Premlata Yadav
- Electronic Materials and Device Laboratory School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
| | - Subhasis Ghosh
- Electronic Materials and Device Laboratory School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
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18
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Graphene growth from reduced graphene oxide by chemical vapour deposition: seeded growth accompanied by restoration. Sci Rep 2016; 6:22653. [PMID: 26961409 PMCID: PMC4785362 DOI: 10.1038/srep22653] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 02/19/2016] [Indexed: 11/17/2022] Open
Abstract
Understanding the underlying mechanisms involved in graphene growth via chemical vapour deposition (CVD) is critical for precise control of the characteristics of graphene. Despite much effort, the actual processes behind graphene synthesis still remain to be elucidated in a large number of aspects. Herein, we report the evolution of graphene properties during in-plane growth of graphene from reduced graphene oxide (RGO) on copper (Cu) via methane CVD. While graphene is laterally grown from RGO flakes on Cu foils up to a few hundred nanometres during CVD process, it shows appreciable improvement in structural quality. The monotonous enhancement of the structural quality of the graphene with increasing length of the graphene growth from RGO suggests that seeded CVD growth of graphene from RGO on Cu surface is accompanied by the restoration of graphitic structure. The finding provides insight into graphene growth and defect reconstruction useful for the production of tailored carbon nanostructures with required properties.
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19
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Entani S, Mizuguchi M, Watanabe H, Antipina LY, Sorokin PB, Avramov PV, Naramoto H, Sakai S. Effective fluorination of single-layer graphene by high-energy ion irradiation through a LiF overlayer. RSC Adv 2016. [DOI: 10.1039/c6ra09631j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new non-chemical method for heteroatom doping into single-layer graphene was demonstrated by high-energy ion irradiation of the graphene-based heterostructure.
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Affiliation(s)
- Shiro Entani
- Quantum Beam Science Directorate
- National Institutes for Quantum and Radiological Science and Technology
- Tokai
- Japan
| | - Masaki Mizuguchi
- Institute for Materials Research
- Tohoku University
- Sendai 980-8577
- Japan
| | - Hideo Watanabe
- Research Institute for Applied Mechanics
- Kyushu University
- Kasuga
- Japan
| | - Liubov Yu. Antipina
- Technological Institute for Superhard and Novel Carbon Materials
- Troitsk
- Russian Federation
- National University of Science and Technology MISiS
- Russian Federation
| | - Pavel B. Sorokin
- Technological Institute for Superhard and Novel Carbon Materials
- Troitsk
- Russian Federation
- National University of Science and Technology MISiS
- Russian Federation
| | | | - Hiroshi Naramoto
- Quantum Beam Science Directorate
- National Institutes for Quantum and Radiological Science and Technology
- Tokai
- Japan
| | - Seiji Sakai
- Quantum Beam Science Directorate
- National Institutes for Quantum and Radiological Science and Technology
- Tokai
- Japan
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20
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Kotakoski J, Brand C, Lilach Y, Cheshnovsky O, Mangler C, Arndt M, Meyer J. Toward Two-Dimensional All-Carbon Heterostructures via Ion Beam Patterning of Single-Layer Graphene. NANO LETTERS 2015; 15:5944-5949. [PMID: 26161575 PMCID: PMC4566131 DOI: 10.1021/acs.nanolett.5b02063] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/06/2015] [Indexed: 05/30/2023]
Abstract
Graphene has many claims to fame: it is the thinnest possible membrane, it has unique electronic and excellent mechanical properties, and it provides the perfect model structure for studying materials science at the atomic level. However, for many practical studies and applications the ordered hexagon arrangement of carbon atoms in graphene is not directly suitable. Here, we show that the atoms can be locally either removed or rearranged into a random pattern of polygons using a focused ion beam (FIB). The atomic structure of the disordered regions is confirmed with atomic-resolution scanning transmission electron microscopy images. These structural modifications can be made on macroscopic scales with a spatial resolution determined only by the size of the ion beam. With just one processing step, three types of structures can be defined within a graphene layer: chemically inert graphene, chemically active amorphous 2D carbon, and empty areas. This, along with the changes in properties, gives promise that FIB patterning of graphene will open the way for creating all-carbon heterostructures to be used in fields ranging from nanoelectronics and chemical sensing to composite materials.
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Affiliation(s)
- Jani Kotakoski
- Faculty of Physics, PNM and Faculty of Physics, VCQ, QuNaBioS, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Christian Brand
- Faculty of Physics, PNM and Faculty of Physics, VCQ, QuNaBioS, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Yigal Lilach
- The Center
for Nanosciences and Nanotechnology and School of Chemistry, The Raymond
and Beverly Faculty of Exact Sciences, Tel
Aviv University, Tel Aviv 69978, Israel
| | - Ori Cheshnovsky
- The Center
for Nanosciences and Nanotechnology and School of Chemistry, The Raymond
and Beverly Faculty of Exact Sciences, Tel
Aviv University, Tel Aviv 69978, Israel
| | - Clemens Mangler
- Faculty of Physics, PNM and Faculty of Physics, VCQ, QuNaBioS, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Markus Arndt
- Faculty of Physics, PNM and Faculty of Physics, VCQ, QuNaBioS, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Jannik
C. Meyer
- Faculty of Physics, PNM and Faculty of Physics, VCQ, QuNaBioS, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
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21
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Barrejón M, Primo A, Gómez-Escalonilla MJ, Fierro JLG, García H, Langa F. Covalent functionalization of N-doped graphene by N-alkylation. Chem Commun (Camb) 2015; 51:16916-9. [DOI: 10.1039/c5cc06285c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-Functionalization of N-graphene is described by the first time. It can be efficiently achieved combining phase transfer catalysis and microwave irradiation. The influence of functionalization on the optical band gap is studied.
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Affiliation(s)
- M. Barrejón
- Universidad de Castilla-La Mancha
- Instituto de Nanociencia
- Nanotecnología y Materiales Moleculares (INAMOL)
- 45071-Toledo
- Spain
| | - A. Primo
- Instituto Universitario de Tecnología Química
- CSIC-UPV
- Universidad Politécnica de Valencia
- 46022-Valencia
- Spain
| | - M. J. Gómez-Escalonilla
- Universidad de Castilla-La Mancha
- Instituto de Nanociencia
- Nanotecnología y Materiales Moleculares (INAMOL)
- 45071-Toledo
- Spain
| | | | - H. García
- Instituto Universitario de Tecnología Química
- CSIC-UPV
- Universidad Politécnica de Valencia
- 46022-Valencia
- Spain
| | - F. Langa
- Universidad de Castilla-La Mancha
- Instituto de Nanociencia
- Nanotecnología y Materiales Moleculares (INAMOL)
- 45071-Toledo
- Spain
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