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Zaabar F, Mahrouche F, Mahtout S, Rabilloud F, Rezouali K. Effects of an external electric field on the electronic properties and optical excitations of germanane and silicane monolayers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:175502. [PMID: 36812601 DOI: 10.1088/1361-648x/acbe25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
Using density functional theory in conjunction with many-body perturbation theory, we theoretically investigated the electronic structures of monolayers germanane and silicane in an applied out-of-plane uniform electric field. Our results show that although the band structures of both monolayers are affected by the electric field, the band gap width cannot be reduced to zero even for high field-strengths. Moreover, excitons are shown to be robust under electric fields, so that Stark shifts for the fundamental exciton peak is only of the order of a few meV for fields of 1 V Å-1. The electric field has also no significant effect on electron probability distribution, as the exciton dissociation into free electron-hole pairs is not observed even at high electric field strengths. Franz-Keldysh effect is also studied in monolayers germanane and silicane. We found that, due to the shielding effect, the external field is prevented to induce absorption in the spectral region below the gap and only above-gap oscillatory spectral features are allowed. One can benefit from such a characteristic where the absorption near the band edge is not altered by the presence of an electric field, especially since these materials have excitonic peaks in the visible range.
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Affiliation(s)
- F Zaabar
- Laboratoire de Physique Théorique, Faculté des sciences exactes, Université de Bejaia, 06000 Bejaia, Algérie
| | - F Mahrouche
- Laboratoire de Physique Théorique, Faculté des sciences exactes, Université de Bejaia, 06000 Bejaia, Algérie
| | - S Mahtout
- Laboratoire de Physique Théorique, Faculté des sciences exactes, Université de Bejaia, 06000 Bejaia, Algérie
| | - F Rabilloud
- Institut Lumière Matière, UMR5306 Université Lyon1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex, France
| | - K Rezouali
- Laboratoire de Physique Théorique, Faculté des sciences exactes, Université de Bejaia, 06000 Bejaia, Algérie
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2
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Abdelsalam H, O. Younis W, Saroka VA, Teleb NH, Yunoki S, Zhang Q. Interaction of hydrated metals with chemically modified hexagonal boron nitride quantum dots: wastewater treatment and water splitting. Phys Chem Chem Phys 2020; 22:2566-2579. [DOI: 10.1039/c9cp06823f] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The electronic and adsorption properties of chemically modified square hexagonal boron nitride quantum dots are investigated using density functional theory calculations.
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Affiliation(s)
- H. Abdelsalam
- School of Materials Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- P. R. China
- Theoretical Physics Department
| | - W. O. Younis
- Vice Presidency for Postgraduate Studies and Scientific Research
- Imam Abdulrahman Bin Faisal University
- Dammam
- Saudi Arabia
| | - V. A. Saroka
- Institute for Nuclear Problems
- Belarusian State University
- 220030 Minsk
- Belarus
- Center for Quantum Spintronics
| | - N. H. Teleb
- Electron Microscope and Thin Films Department
- National Research Centre
- Giza
- Egypt
| | - S. Yunoki
- Computational Condensed Matter Physics Laboratory
- RIKEN
- Wako
- Japan
| | - Q. Zhang
- School of Materials Science and Engineering
- Yancheng Institute of Technology
- Yancheng 224051
- P. R. China
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3
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Serra M, Arenal R, Tenne R. An overview of the recent advances in inorganic nanotubes. NANOSCALE 2019; 11:8073-8090. [PMID: 30994692 DOI: 10.1039/c9nr01880h] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Advanced nanomaterials play a prominent role in nanoscience and nanotechnology developments, opening new frontiers in these areas. Among these nanomaterials, due to their unique characteristics and enhanced chemical and physical properties, inorganic nanotubes have been considered one of the most interesting nanostructures. In recent years, important progress has been achieved in the production and study of these nanomaterials, including boron nitride, transition metal dichalcogenide nanotubular structures, misfit-based nanotubes and other hybrid/doped nanotubular objects. This review is devoted to the in-depth analysis of recent studies on the synthesis, atomic structures, properties and applications of inorganic nanotubes and related nanostructures. Particular attention is paid to the growth mechanism of these nanomaterials. This is a crucial point for the challenges ahead related to the mass production of high-quality defect-free nanotubes for a variety of applications.
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Affiliation(s)
- Marco Serra
- Department of Materials and Interfaces, Weizmann Institute, Herzl Street 234, 76100, Rehovot, Israel.
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4
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Lou P. Quasiparticle energies, exciton level structures and optical absorption spectra of ultra-narrow ZSiCNRs. RSC Adv 2017. [DOI: 10.1039/c7ra09993b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
GW quasiparticle energies, exciton structures and optical absorption spectra of ultra-narrow N-ZSiCNRs.
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Affiliation(s)
- Ping Lou
- Department of Physics
- Anhui University
- Hefei 230039
- China
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5
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Wang L, Li T, Ling L, Luo J, Zhang K, Xu Y, Lu H, Yao Y. Remote catalyzation for growth of boron nitride nanotubes by low pressure chemical vapor deposition. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.03.055] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Zhong H, Quhe R, Wang Y, Ni Z, Ye M, Song Z, Pan Y, Yang J, Yang L, Lei M, Shi J, Lu J. Interfacial Properties of Monolayer and Bilayer MoS2 Contacts with Metals: Beyond the Energy Band Calculations. Sci Rep 2016; 6:21786. [PMID: 26928583 PMCID: PMC4772071 DOI: 10.1038/srep21786] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 02/01/2016] [Indexed: 12/21/2022] Open
Abstract
Although many prototype devices based on two-dimensional (2D) MoS2 have been fabricated and wafer scale growth of 2D MoS2 has been realized, the fundamental nature of 2D MoS2-metal contacts has not been well understood yet. We provide a comprehensive ab initio study of the interfacial properties of a series of monolayer (ML) and bilayer (BL) MoS2-metal contacts (metal = Sc, Ti, Ag, Pt, Ni, and Au). A comparison between the calculated and observed Schottky barrier heights (SBHs) suggests that many-electron effects are strongly suppressed in channel 2D MoS2 due to a charge transfer. The extensively adopted energy band calculation scheme fails to reproduce the observed SBHs in 2D MoS2-Sc interface. By contrast, an ab initio quantum transport device simulation better reproduces the observed SBH in 2D MoS2-Sc interface and highlights the importance of a higher level theoretical approach beyond the energy band calculation in the interface study. BL MoS2-metal contacts generally have a reduced SBH than ML MoS2-metal contacts due to the interlayer coupling and thus have a higher electron injection efficiency.
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Affiliation(s)
- Hongxia Zhong
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Ruge Quhe
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
- State Key Laboratory of Information Photonics and Optical Communications & School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Yangyang Wang
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
- Department of Nuclear Science and Engineering and Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Zeyuan Ni
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Meng Ye
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Zhigang Song
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Yuanyuan Pan
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Jinbo Yang
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, P. R. China
| | - Li Yang
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Ming Lei
- State Key Laboratory of Information Photonics and Optical Communications & School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Junjie Shi
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
| | - Jing Lu
- State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, P. R. China
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7
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Zhuang C, Xu H, Li L, Liu Y, Ban C, Liu X. Systematic investigation of the ball milling–annealing growth and electrical properties of boron nitride nanotubes. RSC Adv 2016. [DOI: 10.1039/c6ra18868k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Boron nitride nanotubes (BNNTs) were grown on stainless-steel substrates by ball milling–annealing in an N2/H2 atmosphere.
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Affiliation(s)
- Cuicui Zhuang
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
| | - Hong Xu
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
| | - Ling Li
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
| | - Yang Liu
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
| | - Chuicheng Ban
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
| | - Xiaowei Liu
- MEMS Center
- Harbin Institute of Technology
- Harbin 150001
- China
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8
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Arenal R, Lopez-Bezanilla A. Boron nitride materials: an overview from 0D to 3D (nano)structures. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2015. [DOI: 10.1002/wcms.1219] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Raul Arenal
- Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA); Universidad de Zaragoza; Zaragoza Spain
- ARAID Foundation; Zaragoza Spain
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9
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Pan Y, Wang Y, Wang L, Zhong H, Quhe R, Ni Z, Ye M, Mei WN, Shi J, Guo W, Yang J, Lu J. Graphdiyne-metal contacts and graphdiyne transistors. NANOSCALE 2015; 7:2116-2127. [PMID: 25562182 DOI: 10.1039/c4nr06541g] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Graphdiyne was prepared on a metal surface, and the preparation of devices using it inevitably involves its contact with metals. Using density functional theory with dispersion correction, we systematically studied, for the first time, the interfacial properties of graphdiyne that is in contact with a series of metals (Al, Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne forms an n-type Ohmic or quasi-Ohmic contact with Al, Ag, and Cu, while it forms a Schottky contact with Pd, Au, Pt, Ni, and Ir (at the source/drain-channel interface), with high Schottky barrier heights of 0.21, 0.46 (n-type), 0.30, 0.41, and 0.46 (p-type) eV, respectively. A graphdiyne field effect transistor (FET) with Al electrodes was simulated using quantum transport calculations. This device exhibits an on-off ratio up to 10(4) and a very large on-state current of 1.3 × 10(4) mA mm(-1) in a 10 nm channel length. Thus, a new prospect has opened up for graphdiyne in high performance nanoscale devices.
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Affiliation(s)
- Yuanyuan Pan
- State Key Laboratory of Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871, P. R. China
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10
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Wang J, Wang Z, Cho H, Kim MJ, Sham TK, Sun X. Layer speciation and electronic structure investigation of freestanding hexagonal boron nitride nanosheets. NANOSCALE 2015; 7:1718-1724. [PMID: 25510407 DOI: 10.1039/c4nr04445b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Chemical imaging, thickness mapping, layer speciation and polarization dependence have been performed on single and multilayered (up to three layers and trilayered nanosheets overlapping to form 6 and 9 layers) hexagonal boron nitride (hBN) nanosheets by scanning transmission X-ray microscopy. Spatially-resolved XANES directly from freestanding regions of different layers has been extracted and compared with sample normal and 30° tilted configurations. Notably a double feature σ* excitonic state and a stable high energy σ* state were observed at the boron site in addition to the intense π* excitonic state. The boron projected σ* DOS, especially the first σ* exciton, is sensitive to surface modification, particularly in the single layered hBN nanosheet which shows more significant detectable contaminants and defects such as tri-coordinated boron/nitrogen oxide. The nitrogen site has shown very weak or no excitonic character. The distinct excitonic effect on boron and nitrogen was interpreted to the partly ionic state of hBN. Bulk XANES of hBN nanosheets was also measured to confirm the spectro-microscopic STXM result. Finally, the unoccupied electronic structures of hBN and graphene were compared.
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Affiliation(s)
- Jian Wang
- Canadian Light Source Inc., University of Saskatchewan, Saskatoon, SK S7N 2V3, Canada
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11
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Ming W, Blair S, Liu F. Quantum size effect on dielectric function of ultrathin metal film: a first-principles study of Al(1 1 1). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:505302. [PMID: 25419653 DOI: 10.1088/0953-8984/26/50/505302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Using first-principles calculations, we show manifestations of the quantum size effect in the dielectric function ε(2) of free-standing Al(1 1 1) ultrathin films of 1 monolayer to 20 monolayers, taking into account size dependent contributions from both interband and intraband electronic transitions. Overall the in-plane components (interband transition) of ε(2) increase with film thickness at all frequencies, converging towards a constant value. However, the out-of-plane components of ε(2) show a more complex behavior, and, only at frequencies less than 0.75 eV, increase with film thickness without convergence. This suggests that ultrathin films can possibly be used for low-loss plasmonics devices in the visible and ultraviolet range. Our findings may shed light on searching for low-loss plasmonic materials via quantum size effect.
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Affiliation(s)
- Wenmei Ming
- Department of Materials Science and Engineering, University of Utah, 201 Presidents Cir, Salt Lake City, UT 84112, USA
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12
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Attaccalite C, Wirtz L, Marini A, Rubio A. Efficient gate-tunable light-emitting device made of defective boron nitride nanotubes: from ultraviolet to the visible. Sci Rep 2014; 3:2698. [PMID: 24060843 PMCID: PMC3781396 DOI: 10.1038/srep02698] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 09/02/2013] [Indexed: 11/28/2022] Open
Abstract
Boron nitride is a promising material for nanotechnology applications due to its two-dimensional graphene-like, insulating, and highly-resistant structure. Recently it has received a lot of attention as a substrate to grow and isolate graphene as well as for its intrinsic UV lasing response. Similar to carbon, one-dimensional boron nitride nanotubes (BNNTs) have been theoretically predicted and later synthesised. Here we use first principles simulations to unambiguously demonstrate that i) BN nanotubes inherit the highly efficient UV luminescence of hexagonal BN; ii) the application of an external perpendicular field closes the electronic gap keeping the UV lasing with lower yield; iii) defects in BNNTS are responsible for tunable light emission from the UV to the visible controlled by a transverse electric field (TEF). Our present findings pave the road towards optoelectronic applications of BN-nanotube-based devices that are simple to implement because they do not require any special doping or complex growth.
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Affiliation(s)
- Claudio Attaccalite
- Institut Néel, CNRS, 25 rue des Martyrs BP 166, 38042 Grenoble cedex 9 France
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13
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Wang S, Li Y, Yip J, Wang J. The excitonic effects in single and double-walled boron nitride nanotubes. J Chem Phys 2014; 140:244701. [PMID: 24985662 DOI: 10.1063/1.4880726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electronic structures and excitonic optical properties of single- and double-walled armchair boron nitride nanotubes (BNNTs) [e.g., (5,5) and (10,10), and (5,5)@(10,10)] are investigated within many-body Green's function and Bethe-Salpeter equation formalism. The first absorption peak of the double-walled nanotube has almost no shift compared with the single-walled (5,5) tube due to the strong optical transition in the double-walled tube that occurs within the inner (5,5) one. Dark and semi-dark excitonic states are detected in the lower energy region, stemming from the charge transfer between inner and outer tubes in the double-walled structure. Most interestingly, the charge transfer makes the electron and the hole reside in different tubes. Moreover, the excited electrons in the double-walled BNNT are able to transfer from the outer tube to the inner one, opposite to that which has been observed in double-walled carbon nanotubes.
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Affiliation(s)
- Shudong Wang
- Department of Physics and Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 211189, China
| | - Yunhai Li
- Department of Physics and Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 211189, China
| | - Joanne Yip
- Institute of Textiles and Clothing, Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Jinlan Wang
- Department of Physics and Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 211189, China
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Hsueh HC, Guo GY, Louie SG. Electronic and Optical Properties of Silicon Carbide Nanostructures. SILICON-BASED NANOMATERIALS 2013. [DOI: 10.1007/978-1-4614-8169-0_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Wang X, Pakdel A, Zhi C, Watanabe K, Sekiguchi T, Golberg D, Bando Y. High-yield boron nitride nanosheets from 'chemical blowing': towards practical applications in polymer composites. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:314205. [PMID: 22820508 DOI: 10.1088/0953-8984/24/31/314205] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
An improved 'chemical blowing' route presuming atmospheric-pressure pre-treatment and moderate heating rate of designated precursors was developed to synthesize ultra-thin boron nitride (BN) nanosheets with high yield and large lateral dimensions. The yield reached as high as 40 wt% with respect to raw materials (ammonia borane). The strong oxygen-related ultraviolet luminescence together with a blue emission of these BN nanosheets was then documented and analyzed. This implies potential applications in solid-state lighting, ultraviolet lasing and full-color luminescence. Mechanical strength of different polymeric composites with a small fraction of BN nanosheet fillers was dramatically increased by tens of per cent, while high transparency of composite materials was still maintained in the visible optical range. The increased yield and reduced cost of BN nanosheets should promote their wide practical applications in various composites.
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Affiliation(s)
- Xuebin Wang
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan.
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Ma F, Zhou ZJ, Liu YT. Li2 Trapped inside Tubiform [n] Boron Nitride Clusters (n=4-8): Structures and First Hyperpolarizability. Chemphyschem 2012; 13:1307-12. [DOI: 10.1002/cphc.201100907] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 01/19/2012] [Indexed: 11/09/2022]
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Wang M, Li CM. Excitonic properties of hydrogen saturation-edged armchair graphene nanoribbons. NANOSCALE 2011; 3:2324-2328. [PMID: 21503364 DOI: 10.1039/c1nr10095e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
First-principle density functional theory calculations with quasiparticle corrections and many body effects are performed to study the electronic and optical properties of armchair graphene nanoribbons (AGNRs) with variant edges saturated by hydrogen atoms. The "effective width" method associated with the reported AGNR family effect is introduced to understand the electronic structures. The method is further confirmed by analyses of the optical transition spectra and the exciton wavefunctions. The optical properties, including the optical transition spectra, exciton binding energies and the distribution of exciton wavefunctions, can be tuned with the hydrogen saturation edge, thus providing an effective way to control the features of the AGNRs.
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Affiliation(s)
- Min Wang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore, 637457
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Miyamoto Y, Zhang H, Rubio A. First-principles simulations of chemical reactions in an HCl molecule embedded inside a C or BN nanotube induced by ultrafast laser pulses. PHYSICAL REVIEW LETTERS 2010; 105:248301. [PMID: 21231562 DOI: 10.1103/physrevlett.105.248301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Indexed: 05/30/2023]
Abstract
We show by first-principles simulations that ultrafast laser pulses induce different chemical reactions in a molecule trapped inside a nanotube. A strong laser pulse polarized perpendicular to the tube axis induces a giant bond stretch of an encapsulated HCl molecule in semiconducting carbon nanotube or in a BN nanotube. Depending on the initial orientation of the HCl molecule, the subsequent laser-induced dynamics is different: either complete disintegration or rebonding of the HCl molecule. Radial motion of the nanotube is always observed and a vacancy appears on the tube wall when the HCl is perpendicular to the tube axis. Those results are important to analyze confined nanochemistry and to manipulate molecules and nanostructures encapsulated in organic and inorganic nanotubes.
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Affiliation(s)
- Yoshiyuki Miyamoto
- Green Innovation Research Laboratories, NEC Corporation, 34 Miyukigaoka, Tsukuba 305-8501, Japan.
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Pacilé D, Papagno M, Skála T, Matolín V, Sainsbury T, Ikuno T, Okawa D, Zettl A, Prince KC. Excitons at the B K edge of boron nitride nanotubes probed by x-ray absorption spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:295301. [PMID: 21399297 DOI: 10.1088/0953-8984/22/29/295301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have performed a near-edge x-ray absorption fine-structure (NEXAFS) investigation of multi-walled boron nitride nanotubes (BNNTs). We show that the one-dimensionality of BNNTs is clearly evident in the B K edge spectrum, while the N K edge spectrum is similar to that of layered hexagonal BN (h-BN). We observe a sharp feature at the σ* onset of the B K edge, which we ascribe to a core exciton state. We also report a comparison with spectra taken after an ammonia plasma treatment, showing that the B K edge becomes indistinguishable from that of h-BN, due to the breaking of the tubular order and the formation of small h-BN clusters.
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Affiliation(s)
- D Pacilé
- Istituto Nazionale di Fisica Nucleare (INFN) and Dipartimento di Fisica Università della Calabria, Cosenza, Italy
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Golberg D, Bando Y, Huang Y, Terao T, Mitome M, Tang C, Zhi C. Boron nitride nanotubes and nanosheets. ACS NANO 2010; 4:2979-93. [PMID: 20462272 DOI: 10.1021/nn1006495] [Citation(s) in RCA: 930] [Impact Index Per Article: 66.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Hexagonal boron nitride (h-BN) is a layered material with a graphite-like structure in which planar networks of BN hexagons are regularly stacked. As the structural analogue of a carbon nanotube (CNT), a BN nanotube (BNNT) was first predicted in 1994; since then, it has become one of the most intriguing non-carbon nanotubes. Compared with metallic or semiconducting CNTs, a BNNT is an electrical insulator with a band gap of ca. 5 eV, basically independent of tube geometry. In addition, BNNTs possess a high chemical stability, excellent mechanical properties, and high thermal conductivity. The same advantages are likely applicable to a graphene analogue-a monatomic layer of a hexagonal BN. Such unique properties make BN nanotubes and nanosheets a promising nanomaterial in a variety of potential fields such as optoelectronic nanodevices, functional composites, hydrogen accumulators, electrically insulating substrates perfectly matching the CNT, and graphene lattices. This review gives an introduction to the rich BN nanotube/nanosheet field, including the latest achievements in the synthesis, structural analyses, and property evaluations, and presents the purpose and significance of this direction in the light of the general nanotube/nanosheet developments.
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Affiliation(s)
- Dmitri Golberg
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 3050044, Japan.
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Li LH, Chen Y. Superhydrophobic properties of nonaligned boron nitride nanotube films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5135-40. [PMID: 20000423 DOI: 10.1021/la903604w] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Superhydrophobicity is highly desirable for numerous applications. Here, we report that a semierect but nonaligned boron nitride nanotube (BNNT) film showed superhydrophobicity with contact angle above 170 degrees and a small contact angle hysteresis. This superhydrophobicity was stable over a large range of drop sizes, and the measured critical transition pressure was about 10 kPa. However, the prostrate BNNT films only showed hydrophobicity. The drop retraction behavior during evaporation, the pressure effect on contact angle, the critical transition pressure, the drop impact behavior, and the self-cleaning efficiency between these two kinds of films were systematically investigated and compared.
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Affiliation(s)
- Lu Hua Li
- Institute for Technology Research and Innovation, Geelong Technology Precinct, Deakin University, Waurn Ponds, Victoria, 3217, Australia
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22
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Park CH, Louie SG. Tunable excitons in biased bilayer graphene. NANO LETTERS 2010; 10:426-31. [PMID: 20078108 DOI: 10.1021/nl902932k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Recent measurements have shown that a continuously tunable bandgap of up to 250 meV can be generated in biased bilayer graphene [ Zhang , Y. ; et al. Nature 2009, 459 , 820 ], opening up pathway for possible graphene-based nanoelectronic and nanophotonic devices operating at room temperature. Here, we show that the optical response of this system is dominated by bound excitons. The main feature of the optical absorbance spectrum is determined by a single symmetric peak arising from excitons, a profile that is markedly different from that of an interband transition picture. Under laboratory conditions, the binding energy of the excitons may be tuned with the external bias going from zero to several tens of millielectronvolts. These novel strong excitonic behaviors result from a peculiar, effective "one-dimensional" joint density of states and a continuously tunable bandgap in biased bilayer graphene. Moreover, we show that the electronic structure (level degeneracy, optical selection rules, etc.) of the bound excitons in a biased bilayer graphene is markedly different from that of a two-dimensional hydrogen atom because of the pseudospin physics.
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Affiliation(s)
- Cheol-Hwan Park
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
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23
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Li LH, Chen Y, Glushenkov AM. Boron nitride nanotube films grown from boron ink painting. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm01414a] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Yu J, Yu D, Chen Y, Chen H, Lin MY, Cheng BM, Li J, Duan W. Narrowed bandgaps and stronger excitonic effects from small boron nitride nanotubes. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.06.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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Gou G, Pan B, Shi L. The Nature of Radiative Transitions in O-Doped Boron Nitride Nanotubes. J Am Chem Soc 2009; 131:4839-45. [DOI: 10.1021/ja809550u] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gaoyang Gou
- Hefei National Laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China, Hefei 230026, P.R. China
| | - Bicai Pan
- Hefei National Laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China, Hefei 230026, P.R. China
| | - Lei Shi
- Hefei National Laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China, Hefei 230026, P.R. China
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26
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Yan B, Park C, Ihm J, Zhou G, Duan W, Park N. Electron Emission Originated from Free-Electron-like States of Alkali-Doped Boron−Nitride Nanotubes. J Am Chem Soc 2008; 130:17012-5. [DOI: 10.1021/ja805557g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Binghai Yan
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
| | - Changwon Park
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
| | - Jisoon Ihm
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
| | - Gang Zhou
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
| | - Wenhui Duan
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
| | - Noejung Park
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea, Center for Advanced Study, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China, and Department of Applied Physics, Dankook University, 126, Jukjeon-dong, Yongin-si, Gyeonggi-do, 448-701, Korea
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27
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Lee CH, Wang J, Kayatsha VK, Huang JY, Yap YK. Effective growth of boron nitride nanotubes by thermal chemical vapor deposition. NANOTECHNOLOGY 2008; 19:455605. [PMID: 21832782 DOI: 10.1088/0957-4484/19/45/455605] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Effective growth of multiwalled boron nitride nanotubes (BNNTs) has been obtained by thermal chemical vapor deposition (CVD). This is achieved by a growth vapor trapping approach as guided by the theory of nucleation. Our results enable the growth of BNNTs in a conventional horizontal tube furnace within an hour at 1200 °C. We found that these BNNTs have an absorption band edge of 5.9 eV, approaching that of single h-BN crystals, which are promising for future nanoscale deep-UV light emitting devices.
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Affiliation(s)
- Chee Huei Lee
- Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA
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28
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Park CH, Louie SG. Energy gaps and stark effect in boron nitride nanoribbons. NANO LETTERS 2008; 8:2200-2203. [PMID: 18593205 DOI: 10.1021/nl080695i] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A first-principles investigation of the electronic properties of boron nitride nanoribbons (BNNRs) having either armchair or zigzag shaped edges passivated by hydrogen with widths up to 10 nm is presented. Band gaps of armchair BNNRs exhibit family dependent oscillations as the width increases and, for ribbons wider than 3 nm, converge to a constant value that is 0.02 eV smaller than the bulk band gap of a boron nitride sheet owing to the existence of very weak edge states. The band gap of zigzag BNNRs monotonically decreases and converges to a gap that is 0.7 eV smaller than the bulk gap due to the presence of strong edge states. When a transverse electric field is applied, the band gaps of armchair BNNRs decrease monotonically with the field strength. For the zigzag BNNRs, however, the band gaps and the carrier effective masses either increase or decrease depending on the direction and the strength of the field.
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Affiliation(s)
- Cheol-Hwan Park
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
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29
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Han WQ, Yu HG, Zhi C, Wang J, Liu Z, Sekiguchi T, Bando Y. Isotope effect on band gap and radiative transitions properties of boron nitride nanotubes. NANO LETTERS 2008; 8:491-494. [PMID: 18173295 DOI: 10.1021/nl0726151] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have carried out an isotope study on the band gap and radiative transition spectra of boron nitride nanotubes (BNNTs) using both experimental and theoretical approaches. The direct band gap of BNNTs was determined at 5.38 eV, independent of the nanotube size and isotope substitution, by cathodoluminescences (CL) spectra. At lower energies, several radiative transitions were observed, and an isotope effect was revealed. In particular, we confirmed that the rich CL spectra between 3.0 and 4.2 eV reflect a phonon-electron coupling mechanism, which is characterized by a radiative transition at 4.09 eV. The frequency red shift and peak broadening due to isotopic effect have been observed. Our Fourier transform infrared spectra and density functional theory calculations suggest that those radiative transitions in BNNTs could be generated by a replacement of some nitrogen atoms with oxygen.
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Affiliation(s)
- Wei-Qiang Han
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA.
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30
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Azevedo S, Kaschny JR, de Castilho CMC, Mota FDB. A theoretical investigation of defects in a boron nitride monolayer. NANOTECHNOLOGY 2007; 18:495707. [PMID: 20442488 DOI: 10.1088/0957-4484/18/49/495707] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We have investigated, using first-principles calculations, the energetic stability and structural properties of antisites, vacancies and substitutional carbon defects in a boron nitride monolayer. We have found that the incorporation of a carbon atom substituting for one boron atom, in an N-rich growth condition, or a nitrogen atom, in a B-rich medium, lowers the formation energy, as compared to antisites and vacancy defects. We also verify that defects, inducing an excess of nitrogen or boron, such as N(B) and B(N), are more stable in its reverse atmosphere, i.e. N(B) is more stable in a B-rich growth medium, while B(N) is more stable in a N-rich condition. In addition we have found that the formation energy of a C(N), in a N-rich medium, and C(B) in a B-rich medium, present formation energies comparable to those of the vacancies, V(N) and V(B), respectively.
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Affiliation(s)
- Sérgio Azevedo
- Departamento de Física, Universidade Estadual de Feira de Santana km-03, Br-116 Norte, 44031-460 Feira de Santana, Bahia, Brazil
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31
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Yang L, Park CH, Son YW, Cohen ML, Louie SG. Quasiparticle energies and band gaps in graphene nanoribbons. PHYSICAL REVIEW LETTERS 2007; 99:186801. [PMID: 17995426 DOI: 10.1103/physrevlett.99.186801] [Citation(s) in RCA: 390] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Indexed: 05/25/2023]
Abstract
We present calculations of the quasiparticle energies and band gaps of graphene nanoribbons (GNRs) carried out using a first-principles many-electron Green's function approach within the GW approximation. Because of the quasi-one-dimensional nature of a GNR, electron-electron interaction effects due to the enhanced screened Coulomb interaction and confinement geometry greatly influence the quasiparticle band gap. Compared with previous tight-binding and density functional theory studies, our calculated quasiparticle band gaps show significant self-energy corrections for both armchair and zigzag GNRs, in the range of 0.5-3.0 eV for ribbons of width 2.4-0.4 nm. The quasiparticle band gaps found here suggest that use of GNRs for electronic device components in ambient conditions may be viable.
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Affiliation(s)
- Li Yang
- Department of Physics, University of California at Berkeley, California 94720, USA
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32
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Yang L, Cohen ML, Louie SG. Excitonic effects in the optical spectra of graphene nanoribbons. NANO LETTERS 2007; 7:3112-5. [PMID: 17824720 DOI: 10.1021/nl0716404] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We present a first-principles calculation of the optical properties of armchair-edged graphene nanoribbons (AGNRs) with many-electron effects included. The reduced dimensionality of the AGNRs gives rise to an enhanced electron-hole binding energy for both bright and dark exciton states (0.8-1.4 eV for GNRs with width approximately 1.2 nm) and dramatically changes the optical spectra owing to a near complete transfer of oscillator strength to the exciton states from the continuum transitions. The characteristics of the excitons of the three distinct families of AGNRs are compared and discussed. The enhanced excitonic effects found here are expected to be of importance in optoelectronic applications of graphene-based nanostructures.
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Affiliation(s)
- Li Yang
- Department of Physics, University of California at Berkeley, California 94720, USA
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34
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Enouz S, Stéphan O, Cochon JL, Colliex C, Loiseau A. C-BN patterned single-walled nanotubes synthesized by laser vaporization. NANO LETTERS 2007; 7:1856-62. [PMID: 17585829 DOI: 10.1021/nl070327z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We report on the synthesis of C-BN single-walled nanotubes made of BN nanodomains embedded into a graphene layer. The synthesis process consists of vaporizing, by a continuous CO2 laser, a target made of carbon and boron mixed with a Co/Ni catalyst under N2 atmosphere. High-resolution transmission electron microscopy (HRTEM) and nanoelectron energy loss spectroscopy (nanoEELS) provide direct evidence that boron and nitrogen co-segregate with respect to carbon and form nanodomains within the hexagonal lattice of the graphene layer in a sequential manner. A growth model is proposed to account for the observed C-BN self-organization and to explain how kinetics and local energetics at intermediate states can tailor ultimate single layer BN-C heterojunctions.
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Affiliation(s)
- Shaïma Enouz
- LEM, CNRS-ONERA UMR104, 29 av. de la Division Leclerc, BP72, 92322 Châtillon Cedex, France
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35
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Tang C, Bando Y, Zhi C, Golberg D. Boron–oxygen luminescence centres in boron–nitrogen systems. Chem Commun (Camb) 2007:4599-601. [DOI: 10.1039/b711807d] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Zobelli A, Ewels CP, Gloter A, Seifert G, Stephan O, Csillag S, Colliex C. Defective structure of BN nanotubes: from single vacancies to dislocation lines. NANO LETTERS 2006; 6:1955-60. [PMID: 16968007 DOI: 10.1021/nl061081l] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A combination of electron microscopy and theoretical calculations provides new insights into the structure, electronics, and energetics of point defects and vacancy lines in BN single-wall nanotubes (SWNT). We show that the point defects forming under electron irradiation in the BN SWNTs are primarily divacancies. Due to the partially ionic character of the BN bonding, divacancies behave like an associated Schottky pair, with a dissociation energy of around 8 eV. Clustering of multiple vacancies is energetically favorable and leads to extended defects which locally change the nanotube diameter and chirality. Nevertheless these defects do not alter significantly the band gap energy, and all of them have electronic structure similar to that of BN divacancies. We thus conclude that under irradiation BN SWNT may have a very stable alteration of its electronic and optical properties.
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Affiliation(s)
- A Zobelli
- Laboratoire de Physique des Solides (UMR CNRS 8502), Bât. 510 Université Paris Sud, 91405 Orsay, France.
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Wirtz L, Marini A, Rubio A. Excitons in boron nitride nanotubes: dimensionality effects. PHYSICAL REVIEW LETTERS 2006; 96:126104. [PMID: 16605932 DOI: 10.1103/physrevlett.96.126104] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Indexed: 05/08/2023]
Abstract
We show that the optical absorption spectra of boron nitride (BN) nanotubes are dominated by strongly bound excitons. Our first-principles calculations indicate that the binding energy for the first and dominant excitonic peak depends sensitively on the dimensionality of the system, varying from 0.7 eV in bulk hexagonal BN via 2.1 eV in the single sheet of BN to more than 3 eV in the hypothetical (2, 2) tube. The strongly localized nature of this exciton dictates the fast convergence of its binding energy with increasing tube diameter towards the sheet value. The absolute position of the first excitonic peak is almost independent of the tube radius and system dimensionality. This provides an explanation for the observed "optical gap" constancy for different tubes and bulk hexagonal BN.
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Affiliation(s)
- Ludger Wirtz
- Institute for Electronics, Microelectronics, and Nanotechnology (IEMN), CNRS-UMR 8520, B.P. 60069, 59652 Villeneuve d'Ascq Cedex, France
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Chapter 2 Predicting Materials and Properties: Theory of the Ground and Excited State. CONCEPTUAL FOUNDATIONS OF MATERIALS - A STANDARD MODEL FOR GROUND- AND EXCITED-STATE PROPERTIES 2006. [DOI: 10.1016/s1572-0934(06)02002-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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