251
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Chang H, Kang J, Chen L, Wang J, Ohmura K, Chen N, Fujita T, Wu H, Chen M. Low-temperature solution-processable Ni(OH)2 ultrathin nanosheet/N-graphene nanohybrids for high-performance supercapacitor electrodes. NANOSCALE 2014; 6:5960-6. [PMID: 24769688 DOI: 10.1039/c4nr00655k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
A novel and facile strategy is developed to fabricate highly nitrogen-doped graphene (N-graphene) based layered, quasi-two-dimensional nanohybrids with ultrathin nanosheet nanocrystals using a low-temperature, solution processing method for high-performance supercapacitor electrodes. High N doping can be achieved together with one of the lowest oxygen content in chemically reduced graphene and related nanohybrids at low temperature by large-scale residue defects of chemically reduced graphene. The layered, quasi-two-dimensional nanohybrids or heterostructures of ultrathin Ni(OH)2 nanosheet nanocrystal/N-graphene can be applied in supercapacitor electrodes with ultrahigh capacitances of ∼1551 F g(-1), excellent rate performance in the scan measurements (from 2 mV s(-1) to 100 mV s(-1)) and in the discharge tests (from 1.5 A g(-1) to 30 A g(-1)) and good cycling stability. Moreover, the capacitance of Ni(OH)2 nanosheet/N-graphene nanohybrids is two and one orders of magnitude higher than that for pure nanocrystals and for the physical mixture of nanocrystal/N-graphene, respectively. Electron transfer in supercapacitor electrodes based on nanohybrids is over 100 times faster than that in electrodes from pure nanocrystals and several tens of times faster than that in electrodes from nanocrystal/N-graphene mixtures. This low-temperature method may provide a low-cost, solution-processable and easily scalable route to high-performance graphene nanohybrid electrodes for energy applications.
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Affiliation(s)
- Haixin Chang
- State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China.
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252
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Ma C, Sun H, Zhao Y, Li B, Li Q, Zhao A, Wang X, Luo Y, Yang J, Wang B, Hou JG. Evidence of van Hove singularities in ordered grain boundaries of graphene. PHYSICAL REVIEW LETTERS 2014; 112:226802. [PMID: 24949783 DOI: 10.1103/physrevlett.112.226802] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Indexed: 06/03/2023]
Abstract
It has long been under debate whether the electron transport performance of graphene could be enhanced by the possible occurrence of van Hove singularities in grain boundaries. Here, we provide direct experimental evidence to confirm the existence of van Hove singularity states close to the Fermi energy in certain ordered grain boundaries using scanning tunneling microscopy. The intrinsic atomic and electronic structures of two ordered grain boundaries, one with alternative pentagon and heptagon rings and the other with alternative pentagon pair and octagon rings, are determined. It is firmly verified that the carrier concentration and, thus, the conductance around ordered grain boundaries can be significantly enhanced by the van Hove singularity states. This finding strongly suggests that a graphene nanoribbon with a properly embedded ordered grain boundary can be a promising structure to improve the performance of graphene-based electronic devices.
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Affiliation(s)
- Chuanxu Ma
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Haifeng Sun
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yeliang Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Bin Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Qunxiang Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Aidi Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Xiaoping Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yi Luo
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Jinlong Yang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Bing Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - J G Hou
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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253
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Gong PL, Huang LF, Zheng XH, Cao TF, Song LL, Zeng Z. The mechanisms of impurity–impurity and impurity–matrix interactions in B/N-doped graphene. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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254
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Xiang Z, Cao D, Huang L, Shui J, Wang M, Dai L. Nitrogen-doped holey graphitic carbon from 2D covalent organic polymers for oxygen reduction. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:3315-20. [PMID: 24664790 DOI: 10.1002/adma.201306328] [Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 02/05/2014] [Indexed: 05/27/2023]
Abstract
Using covalent organic polymer pre-cursors, we have developed a new strategy for location control of N-dopant heteroatoms in the graphitic porous carbon, which otherwise is impossible to achieve with conventional N-doping techniques. The electrocatalytic activities of the N-doped holey graphene analogues are well correlated to the N-locations, showing possibility for tailoring the structure and property of N-doped carbon nanomaterials.
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Affiliation(s)
- Zhonghua Xiang
- State Key Lab of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
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255
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Wei Y, Zhan H, Xia K, Zhang W, Sang S, Gu Y. Resonance of graphene nanoribbons doped with nitrogen and boron: a molecular dynamics study. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:717-725. [PMID: 24991509 PMCID: PMC4077460 DOI: 10.3762/bjnano.5.84] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 04/22/2014] [Indexed: 06/03/2023]
Abstract
Based on its enticing properties, graphene has been envisioned with applications in the area of electronics, photonics, sensors, bio-applications and others. To facilitate various applications, doping has been frequently used to manipulate the properties of graphene. Despite a number of studies conducted on doped graphene regarding its electrical and chemical properties, the impact of doping on the mechanical properties of graphene has been rarely discussed. A systematic study of the vibrational properties of graphene doped with nitrogen and boron is performed by means of a molecular dynamics simulation. The influence from different density or species of dopants has been assessed. It is found that the impacts on the quality factor, Q, resulting from different densities of dopants vary greatly, while the influence on the resonance frequency is insignificant. The reduction of the resonance frequency caused by doping with boron only is larger than the reduction caused by doping with both boron and nitrogen. This study gives a fundamental understanding of the resonance of graphene with different dopants, which may benefit their application as resonators.
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Affiliation(s)
- Ye Wei
- MicroNano System Research Center, Key Lab of Advanced Transducers and Intelligent Control System of the Ministry of Education & College of Information Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
- School of Chemistry, Physics and mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4109, Australia
| | - Haifei Zhan
- School of Chemistry, Physics and mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4109, Australia
| | - Kang Xia
- School of Chemistry, Physics and mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4109, Australia
| | - Wendong Zhang
- MicroNano System Research Center, Key Lab of Advanced Transducers and Intelligent Control System of the Ministry of Education & College of Information Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
| | - Shengbo Sang
- MicroNano System Research Center, Key Lab of Advanced Transducers and Intelligent Control System of the Ministry of Education & College of Information Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
| | - Yuantong Gu
- School of Chemistry, Physics and mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4109, Australia
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256
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Formation of nitrogen-doped graphene nanoscrolls by adsorption of magnetic γ-Fe2O3 nanoparticles. Nat Commun 2014; 4:2319. [PMID: 23942280 DOI: 10.1038/ncomms3319] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 07/18/2013] [Indexed: 12/14/2022] Open
Abstract
Graphene nanoscrolls are Archimedean-type spirals formed by rolling single-layer graphene sheets. Their unique structure makes them conceptually interesting and understanding their formation gives important information on the manipulation and characteristics of various carbon nanostructures. Here we report a 100% efficient process to transform nitrogen-doped reduced graphene oxide sheets into homogeneous nanoscrolls by decoration with magnetic γ-Fe2O3 nanoparticles. Through a large number of control experiments, magnetic characterization of the decorated nanoparticles, and ab initio calculations, we conclude that the rolling is initiated by the strong adsorption of maghemite nanoparticles at nitrogen defects in the graphene lattice and their mutual magnetic interaction. The nanoscroll formation is fully reversible and upon removal of the maghemite nanoparticles, the nanoscrolls return to open sheets. Besides supplying information on the rolling mechanism of graphene nanoscrolls, our results also provide important information on the stabilization of iron oxide nanoparticles.
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257
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Liu M, Zhang R, Chen W. Graphene-supported nanoelectrocatalysts for fuel cells: synthesis, properties, and applications. Chem Rev 2014; 114:5117-60. [PMID: 24666160 DOI: 10.1021/cr400523y] [Citation(s) in RCA: 807] [Impact Index Per Article: 80.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Minmin Liu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, Jilin, China
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258
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Robertson AW, Lee GD, He K, Yoon E, Kirkland AI, Warner JH. Stability and dynamics of the tetravacancy in graphene. NANO LETTERS 2014; 14:1634-1642. [PMID: 24588782 DOI: 10.1021/nl500119p] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The relative prevalence of various configurations of the tetravacancy defect in monolayer graphene has been examined using aberration corrected transmission electron microscopy (TEM). It was found that the two most common structures are extended linear defect structures, with the 3-fold symmetric Y-tetravacancy seldom imaged, in spite of this being a low energy state. Using density functional theory and tight-binding molecular dynamics calculations, we have determined that our TEM observations support a dynamic model of the tetravacancy under electron irradiation, with Stone-Wales bond rotations providing a mechanism for defect relaxation into lowest energy configurations. The most prevalent tetravacancy structures, while not necessarily having the lowest formation energy, are found to have a local energy minimum in the overall energy landscape for tetravacancies, explaining their relatively high occurrence.
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Affiliation(s)
- Alex W Robertson
- Department of Materials, University of Oxford , Parks Road, Oxford OX1 3PH, United Kingdom
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259
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Kim HS, Lee SJ, Kim YH. Distinct mechanisms of DNA sensing based on N-doped carbon nanotubes with enhanced conductance and chemical selectivity. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:774-81. [PMID: 24038933 DOI: 10.1002/smll.201301225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/22/2013] [Indexed: 05/25/2023]
Abstract
N-doped capped carbon nanotube (CNT) electrodes applied to DNA sequencing are studied by first-principles calculations. For the face-on nucleobase junction configurations, a conventional conductance ordering is obtained where the largest signal results from guanine according to its high highest occupied molecular orbital (HOMO) level, whereas for the edge-on counterparts a distinct conductance ordering is observed where the low-HOMO thymine provides the largest signal. The edge-on mode is shown to operate based on a novel molecular sensing mechanism that reflects the chemical connectivity between N-doped CNT caps that can act both as electron donors and electron acceptors and DNA functional groups that include the hyperconjugated thymine methyl group.
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Affiliation(s)
- Han Seul Kim
- Graduate School of EEWS KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
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260
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Itoi H, Nishihara H, Ishii T, Nueangnoraj K, Berenguer-Betrián R, Kyotani T. Large Pseudocapacitance in Quinone-Functionalized Zeolite-Templated Carbon. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2014. [DOI: 10.1246/bcsj.20130292] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Hiroyuki Itoi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
- Department of Applied Chemistry, Faculty of Engineering, Aichi Institute of Technology
| | - Hirotomo Nishihara
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
| | - Takafumi Ishii
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
| | - Khanin Nueangnoraj
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
| | - Raúl Berenguer-Betrián
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
- Chemical Engineering Department, School of Industrial Engineering, University of Malaga
| | - Takashi Kyotani
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
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261
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Wan W, Li H, Huang H, Wong SL, Lv L, Gao Y, Wee ATS. Incorporating isolated molybdenum (Mo) atoms into bilayer epitaxial graphene on 4H-SiC(0001). ACS NANO 2014; 8:970-976. [PMID: 24354296 DOI: 10.1021/nn4057929] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The atomic structures and electronic properties of isolated Mo atoms in bilayer epitaxial graphene (BLEG) on 4H-SiC(0001) are investigated by low temperature scanning tunneling microscopy (LT-STM). LT-STM results reveal that isolated Mo dopants prefer to substitute C atoms at α-sites and preferentially locate between the graphene bilayers. First-principles calculations confirm that the embedding of single Mo dopants within BLEG is energetically favorable as compared to monolayer graphene. The calculated band structures show that Mo-incorporated BLEG is n-doped, and each Mo atom introduces a local magnetic moment of 1.81 μB into BLEG. Our findings demonstrate a simple and stable method to incorporate single transition metal dopants into the graphene lattice to tune its electronic and magnetic properties for possible use in graphene spin devices.
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Affiliation(s)
- Wen Wan
- Institute of Super-microstructure and Ultrafast Process in Advanced Materials, School of Physics and Electronics, The Central South University , Changsha, Hunan 410083, PR China
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262
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Zabet-Khosousi A, Zhao L, Pálová L, Hybertsen MS, Reichman DR, Pasupathy AN, Flynn GW. Segregation of Sublattice Domains in Nitrogen-Doped Graphene. J Am Chem Soc 2014; 136:1391-7. [DOI: 10.1021/ja408463g] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Amir Zabet-Khosousi
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Liuyan Zhao
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - Lucia Pálová
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Mark S. Hybertsen
- Center
for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - David R. Reichman
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Abhay N. Pasupathy
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - George W. Flynn
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
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263
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Maiti UN, Lee WJ, Lee JM, Oh Y, Kim JY, Kim JE, Shim J, Han TH, Kim SO. 25th anniversary article: Chemically modified/doped carbon nanotubes & graphene for optimized nanostructures & nanodevices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:40-66. [PMID: 24123343 DOI: 10.1002/adma.201303265] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Indexed: 05/25/2023]
Abstract
Outstanding pristine properties of carbon nanotubes and graphene have limited the scope for real-life applications without precise controllability of the material structures and properties. This invited article to celebrate the 25th anniversary of Advanced Materials reviews the current research status in the chemical modification/doping of carbon nanotubes and graphene and their relevant applications with optimized structures and properties. A broad aspect of specific correlations between chemical modification/doping schemes of the graphitic carbons with their novel tunable material properties is summarized. An overview of the practical benefits from chemical modification/doping, including the controllability of electronic energy level, charge carrier density, surface energy and surface reactivity for diverse advanced applications is presented, namely flexible electronics/optoelectronics, energy conversion/storage, nanocomposites, and environmental remediation, with a particular emphasis on their optimized interfacial structures and properties. Future research direction is also proposed to surpass existing technological bottlenecks and realize idealized graphitic carbon applications.
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Affiliation(s)
- Uday Narayan Maiti
- Center for Nanomaterials and Chemical Reactions Institute for Basic Science, (IBS), Department of Materials Science & Engineering, KAIST, Daejeon, 305-701, Republic of Korea
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264
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Ostrowski JHJ, Eaves JD. The tunable hydrophobic effect on electrically doped graphene. J Phys Chem B 2014; 118:530-6. [PMID: 24328210 DOI: 10.1021/jp409342n] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using molecular dynamics simulations, we study the hydrophobic effect on electrically doped single layer graphene. With doping levels measured in volts, large changes in contact angle occur for modest voltages applied to the sheet. The effect can be understood as a renormalization of the surface tension between graphene and water in the presence of an electric field generated by the dopant charge, an entirely collective effect termed electrowetting. Because the electronic density of states scales linearly in the vicinity of the Fermi energy, the cosine of the contact angle scales quartically with the applied voltage rather than quadratically, as it would for a two-dimensional metal or in multiple layer graphene. While electrowetting explains the phenomenon, it does not account for the slight asymmetry observed in the hydrophobic response between n- and p-doping.
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Affiliation(s)
- Joseph H J Ostrowski
- Department of Chemistry and Biochemistry, 215 UCB, University of Colorado at Boulder , Boulder, Colorado 80309, United States
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265
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Srivastava D, Susi T, Borghei M, Kari L. Dissociation of oxygen on pristine and nitrogen-doped carbon nanotubes: a spin-polarized density functional study. RSC Adv 2014. [DOI: 10.1039/c3ra47784c] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The oxygen adsorption energies for pristine and N-doped single-walled carbon nanotubes of different diameters.
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Affiliation(s)
| | - Toma Susi
- Department of Applied Physics
- Aalto University
- 00076 Aalto, Finland
| | - Maryam Borghei
- Department of Applied Physics
- Aalto University
- 00076 Aalto, Finland
| | - Laasonen Kari
- Department of Chemistry
- Aalto University
- 00076 Aalto, Finland
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266
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Yan R, Wu H, Zheng Q, Wang J, Huang J, Ding K, Guo Q, Wang J. Graphene quantum dots cut from graphene flakes: high electrocatalytic activity for oxygen reduction and low cytotoxicity. RSC Adv 2014. [DOI: 10.1039/c4ra02336f] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
3–8 nm sized high quality graphene quantum dots with zigzag edges and multi-heteroatom doping were synthesized through a green process of electrochemically cutting pristine few-layer graphene flakes.
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Affiliation(s)
- Rui Yan
- Key Laboratory of Carbon Materials
- Institute of Coal Chemistry
- Chinese Academy of Science
- Taiyuan, PR China
- University of Chinese Academy of Sciences
| | - Hao Wu
- College of Life sciences and Bioengineering
- Beijing Jiaotong University
- Beijing 100044, PR China
| | - Qing Zheng
- College of Life sciences and Bioengineering
- Beijing Jiaotong University
- Beijing 100044, PR China
| | - Junying Wang
- Key Laboratory of Carbon Materials
- Institute of Coal Chemistry
- Chinese Academy of Science
- Taiyuan, PR China
| | - Jianlin Huang
- Key Laboratory of Carbon Materials
- Institute of Coal Chemistry
- Chinese Academy of Science
- Taiyuan, PR China
| | - Kejian Ding
- College of Life sciences and Bioengineering
- Beijing Jiaotong University
- Beijing 100044, PR China
| | - Quangui Guo
- Key Laboratory of Carbon Materials
- Institute of Coal Chemistry
- Chinese Academy of Science
- Taiyuan, PR China
| | - Junzhong Wang
- Key Laboratory of Carbon Materials
- Institute of Coal Chemistry
- Chinese Academy of Science
- Taiyuan, PR China
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267
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Schultz BJ, Dennis RV, Aldinger JP, Jaye C, Wang X, Fischer DA, Cartwright AN, Banerjee S. X-ray absorption spectroscopy studies of electronic structure recovery and nitrogen local structure upon thermal reduction of graphene oxide in an ammonia environment. RSC Adv 2014. [DOI: 10.1039/c3ra45591b] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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268
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Zhou J, Shan X, Ma J, Gu Y, Qian Z, Chen J, Feng H. Facile synthesis of P-doped carbon quantum dots with highly efficient photoluminescence. RSC Adv 2014. [DOI: 10.1039/c3ra45294h] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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269
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Gunathilake SS, Huang P, Bhatt MP, Rainbolt EA, Stefan MC, Biewer MC. Nitrogen containing graphene-like structures from pyrolysis of pyrimidine polymers for polymer/graphene hybrid field effect transistors. RSC Adv 2014. [DOI: 10.1039/c4ra06498d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synthesis of pyrimidine polymers, their pyrolysis to obtain nitrogen containing graphene like structures and application of these graphitic materials in polymer/graphene hybrid field effect transistors is reported.
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Affiliation(s)
| | - Peishen Huang
- University of Texas at Dallas
- Department of Chemistry
- Richardson, USA
| | - Mahesh P. Bhatt
- University of Texas at Dallas
- Department of Chemistry
- Richardson, USA
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270
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Xue Y, Wu B, Liu H, Tan J, Hu W, Liu Y. Direct synthesis of phosphorus and nitrogen co-doped monolayer graphene with air-stable n-type characteristics. Phys Chem Chem Phys 2014; 16:20392-7. [DOI: 10.1039/c4cp02935f] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Large-area substitutional phosphorus–nitrogen co-doped monolayer graphene is directly synthesized on a Cu surface by chemical vapor deposition using molecules of phosphonitrilic chloride trimer as the phosphorus and nitrogen sources.
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Affiliation(s)
- Yunzhou Xue
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
| | - Bin Wu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
| | - Hongtao Liu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
| | - Jiahui Tan
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
| | - Wenping Hu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
| | - Yunqi Liu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190, P. R. China
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271
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Fujii S, Enoki T. Rearrangement of π-electron network and switching of edge-localized π state in reduced graphene oxide. ACS NANO 2013; 7:11190-11199. [PMID: 24206107 DOI: 10.1021/nn404937z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Introduced defects can modulate the intrinsic electronic structure of graphene, causing a drastic switch in its electronic and magnetic properties, in which defect-induced localized π states near the Fermi level play an important role. Accordingly, considerable effort has been directed toward detailed characterization of the defect-induced state; however, identification of the chemical nature of the defect-induced state remains a challenge. Here, we demonstrate a method for reliable identification of the localized π states of oxidized vacancy edges in reduced graphene oxide. Depending on the dynamic changes in the oxygen-binding modes, i.e., between carbonyl and ether forms in the vacancy edges, the π-electron network near the edges can rearrange, leading to drastic on-off switching of the localized π state. This switching can be manipulated via scanning-probe-induced local mechanical force. This study provides fundamental guidance toward understanding how oxidized defect structures contribute to the unique electronic state of graphene oxide and its potential future applications in electronic devices.
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Affiliation(s)
- Shintaro Fujii
- Department of Chemistry, Tokyo Institute of Technology , 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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272
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Eigler S, Hu Y, Ishii Y, Hirsch A. Controlled functionalization of graphene oxide with sodium azide. NANOSCALE 2013; 5:12136-9. [PMID: 24162364 PMCID: PMC3880578 DOI: 10.1039/c3nr04332k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We present the first example of azide functionalization on the surface of graphene oxide (GO), which preserves thermally unstable groups in GO through the mild reaction with sodium azide in solids. Experimental evidence, by (15)N solid-state NMR and other spectroscopic methods, indicates the substitution of organosulfate with azide anions as the reaction mechanism.
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Affiliation(s)
- Siegfried Eigler
- Department of Chemistry and Pharmacy, Institute of Advanced Materials and Processes (ZMP), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Dr-Mack Str. 81, 90762 Fürth, Germany.
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273
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Probing Dirac Fermions in Graphene by Scanning Tunneling Microscopy and Spectroscopy. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/978-3-319-02633-6_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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274
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Hu T, Sun X, Sun H, Xin G, Shao D, Liu C, Lian J. Rapid synthesis of nitrogen-doped graphene for a lithium ion battery anode with excellent rate performance and super-long cyclic stability. Phys Chem Chem Phys 2013; 16:1060-6. [PMID: 24287587 DOI: 10.1039/c3cp54494j] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Chemical doping of nitrogen into graphene can significantly enhance the reversible capacity and cyclic stability of the graphene-based lithium ion battery (LIB) anodes, and first principles calculations based on density functional theory suggested that pyridinic-N shows stronger binding with Li with reduced energy barrier for Li diffusion and thus is more effective for Li storage than pyrrolic and graphitic-N. Here, we report a novel and rapid (~30 seconds) process to fabricate nitrogen-doped graphene (NGr) by simultaneous thermal reduction of graphene oxide with ammonium hydroxide. The porous NGr with dominant pyridinic N atoms displays greatly enhanced reversible capacities, rate performance and exceptional cyclic stability as compared with pristine graphene. The reversible discharge capacity of the NGr electrode cycled between 0.01-3 V can reach 453 mA h g(-1) after 550 cycles at a charge rate of 2 A g(-1) (~5.4 C), and 180 mA h g(-1) after 2000 cycles at a high charge rate of 10 A g(-1) (~27 C) without any capacity fading. When charged within 0.01-1.5 V, the NGr anode still exhibits high reversible capacities of 224 mA h g(-1) and 169 mA h g(-1) after 700 cycles and 800 cycles at a charge rate of 1 A g(-1) and 5 A g(-1), respectively. Ex situ X-ray photoelectron spectroscopy (XPS) analysis of the NGr electrode upon lithiation and delithiation indicated that the pyridinic-N dominates the capacity enhancement at 3 V, while the pyrrolic-N contributes primarily to Li ion storage below 1.5 V.
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Affiliation(s)
- Tao Hu
- Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education Northeastern University, Shenyang, Liaoning 110004, China
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275
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Liu X, Antonietti M. Moderating black powder chemistry for the synthesis of doped and highly porous graphene nanoplatelets and their use in electrocatalysis. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:6284-6290. [PMID: 23963790 DOI: 10.1002/adma.201302034] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/03/2013] [Indexed: 06/02/2023]
Abstract
Inspired by black powder explosion, a mixture of sugar and nitrate is diluted with inert molten salt, such that their rapid reaction is moderated, allowing capturing of the intermediacy product: highly porous N-doped graphene nanoplates. The methodology is extended to S-doped porous carbon sheets by replacing the nitrate with sulfate. These MS-derived carbons show promising performances towards electrocatalysis and capacitive energy storage.
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Affiliation(s)
- Xiaofeng Liu
- Department of Colloid Chemistry, Max-Planck Institute of Colloids and Interfaces, Research Campus Golm, D-14424, Potsdam, Germany
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276
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Zhang J, Wang Z, Zhu Z. A density functional theory study on oxygen reduction reaction on nitrogen-doped graphene. J Mol Model 2013; 19:5515-21. [PMID: 24241180 DOI: 10.1007/s00894-013-2047-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 10/21/2013] [Indexed: 11/25/2022]
Abstract
Nitrogen (N)-doped carbons reportedly exhibit good electrocatalytic activity for the oxygen reduction reaction (ORR) of fuel cells. This work provides theoretical insights into the ORR mechanism of N-doped graphene by using density functional theory calculations. All possible reaction pathways were investigated, and the transition state of each elementary step was identified. The results showed that OOH reduction was easier than O-OH breaking. OOH reduction followed a direct Eley-Rideal mechanism (the OOH species was in gas phase, but H was chemisorbed on the surface) with a significantly low reaction barrier of 0.09 eV. Pathways for both four-electron and two-electron reductions were possible. The rate-determining step of the two-electron pathway was the reduction of O₂ (formation of OOH), whereas that of the four-electron pathway was the reduction of OH into H₂O. After comparing the barriers of the rate-determining steps of the two pathways, we found that the two-electron pathway was more energetically favored than the four-electron pathway.
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Affiliation(s)
- Jing Zhang
- State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi, 030001, China
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277
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Wei D, Kivioja J. Graphene for energy solutions and its industrialization. NANOSCALE 2013; 5:10108-10126. [PMID: 24057074 DOI: 10.1039/c3nr03312k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Graphene attracts intensive interest globally across academia and industry since the award of the Nobel Prize in Physics 2010. Within the last half decade, there has been an explosion in the number of scientific publications, patents and industry projects involved in this topic. On the other hand, energy is one of the biggest challenges of this century and related to the global sustainable economy. There are many reviews on graphene and its applications in various devices, however, few of the review articles connect the intrinsic properties of graphene with its energy. The IUPAC definition of graphene refers to a single carbon layer of graphite structure and its related superlative properties. A lot of scientific results on graphene published to date are actually dealing with multi-layer graphenes or reduced graphenes from insulating graphene oxides (GO) which contain defects and contaminants from the reactions and do not possess some of the intrinsic physical properties of pristine graphene. In this review, the focus is on the most recent advances in the study of pure graphene properties and novel energy solutions based on these properties. It also includes graphene metrology and analysis of both intellectual property and the value chain for the existing and forthcoming graphene industry that may cause a new 'industry revolution' with the strong and determined support of governments and industries across the European Union, U. S., Asia and many other countries in the world.
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Affiliation(s)
- Di Wei
- Nokia Research Center, Broers Building, 21 J. J. Thomson Avenue, Cambridge, CB3 0FA, UK.
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278
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Zhao W, Gebhardt J, Gotterbarm K, Höfert O, Gleichweit C, Papp C, Görling A, Steinrück HP. Gold intercalation of boron-doped graphene on Ni(111): XPS and DFT study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:445002. [PMID: 24056002 DOI: 10.1088/0953-8984/25/44/445002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The intercalation of a graphene layer adsorbed on a metal surface by gold or other metals is a standard procedure. While it was previously shown that pristine, i.e., undoped, and nitrogen-doped graphene sheets can be decoupled from a nickel substrate by intercalation with gold atoms in order to produce quasi-free-standing graphene, we find the gold intercalation behavior for boron-doped graphene on a Ni(111) surface to be more complex: for low boron contents (2-5%) in the graphene lattice only partial gold intercalation occurs and for higher boron contents (up to 20%) no intercalation is observed. In order to understand this different behavior, a density functional theory investigation is carried out, comparing undoped as well as substitutional nitrogen- and boron-doped graphene on Ni(111). We identify the stronger binding of the boron atoms to the nickel substrate as the factor responsible for the different intercalation behavior in the case of boron doping. However, the calculations predict that this energetic effect prevents the intercalation process only for large boron concentrations and that it can be overcome for smaller boron coverages, in line with our x-ray photoelectron spectroscopy experiments.
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Affiliation(s)
- W Zhao
- Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstraße 3, D-91058 Erlangen, Germany
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279
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Wang F, Liu G, Rothwell S, Nevius M, Tejeda A, Taleb-Ibrahimi A, Feldman LC, Cohen PI, Conrad EH. Wide-gap semiconducting graphene from nitrogen-seeded SiC. NANO LETTERS 2013; 13:4827-4832. [PMID: 24060338 DOI: 10.1021/nl402544n] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
All carbon electronics based on graphene have been an elusive goal. For more than a decade, the inability to produce significant band-gaps in this material has prevented the development of graphene electronics. We demonstrate a new approach to produce semiconducting graphene that uses a submonolayer concentration of nitrogen on SiC sufficient to pin epitaxial graphene to the SiC interface as it grows. The resulting buckled graphene opens a band gap greater than 0.7 eV in the otherwise continuous metallic graphene sheet.
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Affiliation(s)
- F Wang
- School of Physics, The Georgia Institute of Technology , Atlanta, Georgia 30332-0430, United States
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280
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Bangert U, Pierce W, Kepaptsoglou DM, Ramasse Q, Zan R, Gass MH, Van den Berg JA, Boothroyd CB, Amani J, Hofsäss H. Ion implantation of graphene-toward IC compatible technologies. NANO LETTERS 2013; 13:4902-7. [PMID: 24059439 DOI: 10.1021/nl402812y] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Doping of graphene via low energy ion implantation could open possibilities for fabrication of nanometer-scale patterned graphene-based devices as well as for graphene functionalization compatible with large-scale integrated semiconductor technology. Using advanced electron microscopy/spectroscopy methods, we show for the first time directly that graphene can be doped with B and N via ion implantation and that the retention is in good agreement with predictions from calculation-based literature values. Atomic resolution high-angle dark field imaging (HAADF) combined with single-atom electron energy loss (EEL) spectroscopy reveals that for sufficiently low implantation energies ions are predominantly substitutionally incorporated into the graphene lattice with a very small fraction residing in defect-related sites.
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Affiliation(s)
- U Bangert
- School of Materials, The University of Manchester , Manchester M13 9PL, United Kingdom
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281
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Zhao L, Levendorf M, Goncher S, Schiros T, Pálová L, Zabet-Khosousi A, Rim KT, Gutiérrez C, Nordlund D, Jaye C, Hybertsen M, Reichman D, Flynn GW, Park J, Pasupathy AN. Local atomic and electronic structure of boron chemical doping in monolayer graphene. NANO LETTERS 2013; 13:4659-65. [PMID: 24032458 DOI: 10.1021/nl401781d] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We use scanning tunneling microscopy and X-ray spectroscopy to characterize the atomic and electronic structure of boron-doped and nitrogen-doped graphene created by chemical vapor deposition on copper substrates. Microscopic measurements show that boron, like nitrogen, incorporates into the carbon lattice primarily in the graphitic form and contributes ~0.5 carriers into the graphene sheet per dopant. Density functional theory calculations indicate that boron dopants interact strongly with the underlying copper substrate while nitrogen dopants do not. The local bonding differences between graphitic boron and nitrogen dopants lead to large scale differences in dopant distribution. The distribution of dopants is observed to be completely random in the case of boron, while nitrogen displays strong sublattice clustering. Structurally, nitrogen-doped graphene is relatively defect-free while boron-doped graphene films show a large number of Stone-Wales defects. These defects create local electronic resonances and cause electronic scattering, but do not electronically dope the graphene film.
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Affiliation(s)
- Liuyan Zhao
- Department of Physics, Columbia University , New York, New York 10027, United States
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282
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Huang B, Xiang HJ, Wei SH. Chemical functionalization of silicene: spontaneous structural transition and exotic electronic properties. PHYSICAL REVIEW LETTERS 2013; 111:145502. [PMID: 24138253 DOI: 10.1103/physrevlett.111.145502] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Indexed: 06/02/2023]
Abstract
The use of newly discovered silicene for various optoelectronic applications depends largely on the possibility of controlling its electronic properties by chemical functionalization. To investigate this possibility, we systemically study the structural and electronic properties of chemically functionalized silicene by employing first-principles calculations combined with the cluster expansion approach. Interestingly, we find that chemically functionalized epitaxial silicene is generally accompanied by a spontaneous structural transition, which originates from the preference of sp(3) hybridization of silicon. To realized continuously tunable band gaps, chemical functionalization of freestanding silicene at ~900 K is proposed. Finally, we predict that metastable silicene can also be used as an important host material to produce novel functional materials via substitutional doping. For example, the discovered ordered Si(8)P(4) could be a strong candidate for thin-film solar cell absorbers beyond bulk Si.
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Affiliation(s)
- Bing Huang
- National Renewable Energy Laboratory, Golden, Colorado 80401, USA
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283
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Goran JM, Favela CA, Stevenson KJ. Electrochemical oxidation of dihydronicotinamide adenine dinucleotide at nitrogen-doped carbon nanotube electrodes. Anal Chem 2013; 85:9135-41. [PMID: 23991631 DOI: 10.1021/ac401784b] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitrogen-doped carbon nanotubes (N-CNTs) substantially lower the overpotential necessary for dihydronicotinamide adenine dinucleotide (NADH) oxidation compared to nondoped CNTs or traditional carbon electrodes such as glassy carbon (GC). We observe a 370 mV shift in the peak potential (Ep) from GC to CNTs and another 170 mV shift from CNTs to 7.4 atom % N-CNTs in a sodium phosphate buffer solution (pH 7.0) with 2.0 mM NADH (scan rate 10 mV/s). The sensitivity of 7.4 atom % N-CNTs to NADH was measured at 0.30 ± 0.04 A M(-1) cm(-2), with a limit of detection at 1.1 ± 0.3 μM and a linear range of 70 ± 10 μM poised at a low potential of -0.32 V (vs Hg/Hg2SO4). NADH fouling, known to occur to the electrode surface during NADH oxidation, was investigated by measuring both the change in Ep and the resulting loss of electrode sensitivity. NADH degradation, known to occur in phosphate buffer, was characterized by absorbance at 340 nm and correlated with the loss of NADH electroactivity. N-CNTs are further demonstrated to be an effective platform for dehydrogenase-based biosensing by allowing glucose dehydrogenase to spontaneously adsorb onto the N-CNT surface and measuring the resulting electrode's sensitivity to glucose. The glucose biosensor had a sensitivity of 0.032 ± 0.003 A M(-1) cm(-2), a limit of detection at 6 ± 1 μM, and a linear range of 440 ± 50 μM.
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Affiliation(s)
- Jacob M Goran
- Department of Chemistry and Biochemistry, Center for Electrochemistry, Center for Nano- and Molecular Science and Technology, The University of Texas at Austin , 1 University Station, A5300, Austin, Texas 78712, United States
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284
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Yu YX. Can all nitrogen-doped defects improve the performance of graphene anode materials for lithium-ion batteries? Phys Chem Chem Phys 2013; 15:16819-27. [PMID: 24002442 DOI: 10.1039/c3cp51689j] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The electronic and adsorption properties of graphene can be changed significantly through substitutional doping with nitrogen and nitrogen decoration of vacancies. Here ab initio density functional theory with a dispersion correction was used to investigate the stability, magnetic and adsorption properties of nine defects in graphene, including both nitrogen substitutional doping and nitrogen decoration of vacancies. The results indicate that only pyridinic N2V2 defect in graphene shows a ferromagnetic spin structure with high magnetic moment and magnetic stabilization energy. Not all nitrogen-doped defects can improve the capacity of the lithium-ion batteries. The adsorption energies of a lithium atom on nitrogen-substituted graphenes are more positive, indicating that they are meta-stable and no better than the pristine graphene as anode materials of lithium-ion batteries. Nitrogen-decorated single and double vacancy defects, especially for the pyridinic N2V2 defect in graphene, can greatly improve the reversible capacity of the battery in comparison with the pristine graphene. The theoretical prediction of the reversible capacity of the battery is 1039 mA h g(-1) for the nitrogen-doped graphene material synthesized by Wu et al., which is in good agreement with the experimental data (1043 mA h g(-1)). The theoretical computations suggest that nitrogen-decorated single and double vacancy defects in graphene are the promising candidate for anode materials of lithium-ion batteries. Each nitrogen atom in the decoration can improve the reversible capacity of the battery by 63.3-124.5 mA h g(-1) in a 4 × 4 supercell of graphene. The present work provides crucial information for the development of N-doped graphene-based anode materials of lithium-ion batteries.
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Affiliation(s)
- Yang-Xin Yu
- Laboratory of Chemical Engineering Thermodynamics, Department of Chemical Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
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285
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Tison Y, Lin H, Lagoute J, Repain V, Chacon C, Girard Y, Rousset S, Henrard L, Zheng B, Susi T, Kauppinen EI, Ducastelle F, Loiseau A. Identification of nitrogen dopants in single-walled carbon nanotubes by scanning tunneling microscopy. ACS NANO 2013; 7:7219-7226. [PMID: 23829349 DOI: 10.1021/nn4026146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Using scanning tunnelling microscopy and spectroscopy, we investigated the atomic and electronic structure of nitrogen-doped single walled carbon nanotubes synthesized by chemical vapor deposition. The insertion of nitrogen in the carbon lattice induces several types of point defects involving different atomic configurations. Spectroscopic measurements on semiconducting nanotubes reveal that these local structures can induce either extended shallow levels or more localized deep levels. In a metallic tube, a single doping site associated with a donor state was observed in the gap at an energy close to that of the first van Hove singularity. Density functional theory calculations reveal that this feature corresponds to a substitutional nitrogen atom in the carbon network.
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Affiliation(s)
- Yann Tison
- Laboratoire Matériaux et Phénomènes Quantiques, UMR7162, Université Paris Diderot-Paris 7, Sorbonne Paris Cité, CNRS, UMR 7162 case courrier 7021, 75205 Paris Cedex 13, France.
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286
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Lu YF, Lo ST, Lin JC, Zhang W, Lu JY, Liu FH, Tseng CM, Lee YH, Liang CT, Li LJ. Nitrogen-doped graphene sheets grown by chemical vapor deposition: synthesis and influence of nitrogen impurities on carrier transport. ACS NANO 2013; 7:6522-32. [PMID: 23879622 DOI: 10.1021/nn402102y] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A significant advance toward achieving practical applications of graphene as a two-dimensional material in nanoelectronics would be provided by successful synthesis of both n-type and p-type doped graphene. However, reliable doping and a thorough understanding of carrier transport in the presence of charged impurities governed by ionized donors or acceptors in the graphene lattice are still lacking. Here we report experimental realization of few-layer nitrogen-doped (N-doped) graphene sheets by chemical vapor deposition of organic molecule 1,3,5-triazine on Cu metal catalyst. When reducing the growth temperature, the atomic percentage of nitrogen doping is raised from 2.1% to 5.6%. With increasing doping concentration, N-doped graphene sheet exhibits a crossover from p-type to n-type behavior accompanied by a strong enhancement of electron-hole transport asymmetry, manifesting the influence of incorporated nitrogen impurities. In addition, by analyzing the data of X-ray photoelectron spectroscopy, Raman spectroscopy, and electrical measurements, we show that pyridinic and pyrrolic N impurities play an important role in determining the transport behavior of carriers in our N-doped graphene sheets.
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Affiliation(s)
- Yu-Fen Lu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
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287
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Nicholls RJ, Murdock AT, Tsang J, Britton J, Pennycook TJ, Koós A, Nellist PD, Grobert N, Yates JR. Probing the bonding in nitrogen-doped graphene using electron energy loss spectroscopy. ACS NANO 2013; 7:7145-50. [PMID: 23869545 DOI: 10.1021/nn402489v] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Precise control of graphene properties is an essential step toward the realization of future graphene devices. Defects, such as individual nitrogen atoms, can strongly influence the electronic structure of graphene. Therefore, state-of-the-art characterization techniques, in conjunction with modern modeling tools, are necessary to identify these defects and fully understand the synthesized material. We have directly visualized individual substitutional nitrogen dopant atoms in graphene using scanning transmission electron microscopy and conducted complementary electron energy loss spectroscopy experiments and modeling which demonstrates the influence of the nitrogen atom on the carbon K-edge.
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Affiliation(s)
- Rebecca J Nicholls
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom.
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288
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Blanc N, Jean F, Krasheninnikov AV, Renaud G, Coraux J. Strains induced by point defects in graphene on a metal. PHYSICAL REVIEW LETTERS 2013; 111:085501. [PMID: 24010451 DOI: 10.1103/physrevlett.111.085501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Indexed: 06/02/2023]
Abstract
Strains strongly affect the properties of low-dimensional materials, such as graphene. By combining in situ, in operando, reflection high-energy electron diffraction experiments with first-principles calculations, we show that large strains, above 2%, are present in graphene during its growth by chemical vapor deposition on Ir(111) and when it is subjected to oxygen etching and ion bombardment. Our results unravel the microscopic relationship between point defects and strains in epitaxial graphene and suggest new avenues for graphene nanostructuring and engineering its properties through introduction of defects and intercalation of atoms and molecules between graphene and its metal substrate.
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Affiliation(s)
- Nils Blanc
- Institut NÉEL, CNRS and Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France and CEA-UJF, INAC, SP2M, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
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289
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Muchharla B, Pathak A, Liu Z, Song L, Jayasekera T, Kar S, Vajtai R, Balicas L, Ajayan PM, Talapatra S, Ali N. Tunable electronics in large-area atomic layers of boron-nitrogen-carbon. NANO LETTERS 2013; 13:3476-3481. [PMID: 23859076 DOI: 10.1021/nl400721y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report on the low-temperature electrical transport properties of large area boron and nitrogen codoped graphene layers (BNC). The temperature dependence of resistivity (5 K < T < 400 K) of BNC layers show semiconducting nature and display a band gap which increases with B and N content, in sharp contrast to large area graphene layers, which shows metallic behavior. Our investigations show that the amount of B dominates the semiconducting nature of the BNC layers. This experimental observations agree with the density functional theory (DFT) calculations performed on BNC structures similar in composition to the experimentally measured samples. In addition, the temperature dependence of the electrical conductivity of these samples displays two regimes: at higher temperatures, the doped samples display an Arrhenius-like temperature dependence thus indicating a well-defined band gap. At the lowest temperatures, the temperature dependence of the conductivity deviates from activated behavior and displays a conduction mechanism consistent with Mott's two-dimensional (2D) variable range hopping (2D-VRH). The ability to tune the electronic properties of thin layers of BNC by simply varying the concentration of B and N will provide a tremendous boost for obtaining materials with tunable electronic properties relevant to applications in solid state electronics.
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Affiliation(s)
- Baleeswaraiah Muchharla
- Department of Physics, Southern Illinois University Carbondale, Carbondale, Illinois 62901, United States
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290
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Li B, Su D. Theoretical Studies on Ethylene Selectivity in the Oxidative Dehydrogenation Reaction on Undoped and Doped Nanostructured Carbon Catalysts. Chem Asian J 2013; 8:2605-8. [DOI: 10.1002/asia.201300410] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Bo Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 WenHua Road, ShenYang 110016 (China), Fax: (+86) 24‐83940019
| | - Dangsheng Su
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 WenHua Road, ShenYang 110016 (China), Fax: (+86) 24‐83940019
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291
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Tang Q, Zhou Z, Chen Z. Graphene-related nanomaterials: tuning properties by functionalization. NANOSCALE 2013; 5:4541-83. [PMID: 23443470 DOI: 10.1039/c3nr33218g] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this review, we discuss the most recent progress on graphene-related nanomaterials, including doped graphene and derived graphene nanoribbons, graphene oxide, graphane, fluorographene, graphyne, graphdiyne, and porous graphene, from both experimental and theoretical perspectives, and emphasize tuning their stability, electronic and magnetic properties by chemical functionalization.
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Affiliation(s)
- Qing Tang
- Tianjin Key Laboratory of Metal and Molecule Based Material Chemistry, Institute of New Energy Material Chemistry, Computational Centre for Molecule Science, Nankai University, Tianjin 300071, PR China
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292
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Cresti A, Ortmann F, Louvet T, Van Tuan D, Roche S. Broken symmetries, zero-energy modes, and quantum transport in disordered graphene: from supermetallic to insulating regimes. PHYSICAL REVIEW LETTERS 2013; 110:196601. [PMID: 23705730 DOI: 10.1103/physrevlett.110.196601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 02/14/2013] [Indexed: 06/02/2023]
Abstract
The role of defect-induced zero-energy modes on charge transport in graphene is investigated using Kubo and Landauer transport calculations. By tuning the density of random distributions of monovacancies either equally populating the two sublattices or exclusively located on a single sublattice, all conduction regimes are covered from direct tunneling through evanescent modes to mesoscopic transport in bulk disordered graphene. Depending on the transport measurement geometry, defect density, and broken sublattice symmetry, the Dirac-point conductivity is either exceptionally robust against disorder (supermetallic state) or suppressed through a gap opening or by algebraic localization of zero-energy modes, whereas weak localization and the Anderson insulating regime are obtained for higher energies. These findings clarify the contribution of zero-energy modes to transport at the Dirac point, hitherto controversial.
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Affiliation(s)
- Alessandro Cresti
- IMEP-LAHC (UMR CNRS/INPG/UJF 5130), Grenoble INP, Minatec, 3, Parvis Louis Néel, BP 257, F-38016 Grenoble, France
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293
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Zhang L, Zhou L, Yang M, Liu Z, Xie Q, Peng H, Liu Z. Photo-induced free radical modification of graphene. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:1134-1143. [PMID: 23512797 DOI: 10.1002/smll.201203152] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 02/04/2013] [Indexed: 06/01/2023]
Abstract
Graphene has stimulated enormous interest due to its intriguing structure and fascinating properties. The extremely high carrier mobility, mechanical flexibility, and optical transparency as well as the versatility for band structure engineering make graphene a promising candidate for next-generation carbon-based electronic devices. Graphene chemistry, the covalent functionalization of graphene as a 2D giant molecule, offers a promising direction to controllably tailor its properties through the introduction of various chemical decorations. One of the great challenges for graphene functionalization originates from its strong chemical stability, thus highly reactive chemical species are needed as the reactants. In recent years, novel photochemical approaches have been developed to achieve efficient graphene modification and bandgap modulation, following a general concept of "Photochemical Bandgap Engineering of Graphene". In this article, such kinds of photochemical graphene engineering are demonstrated, together with a brief discussion on the future directions, challenges, and opportunities in this fascinating research area.
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Affiliation(s)
- Liming Zhang
- Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China
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294
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Lherbier A, Botello-Méndez AR, Charlier JC. Electronic and transport properties of unbalanced sublattice N-doping in graphene. NANO LETTERS 2013; 13:1446-1450. [PMID: 23477418 DOI: 10.1021/nl304351z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Using both first-principles techniques and a real-space Kubo-Greenwood approach, electronic and transport properties of nitrogen-doped graphene with a single sublattice preference are investigated. Such a breaking of the sublattice symmetry leads to the appearance of a true band gap in graphene electronic spectrum even for a random distribution of the N dopants. More surprisingly, a natural spatial separation of both types of charge carriers at the band edge is predicted, leading to a highly asymmetric electronic transport. Both the presence of a band gap, allowing large on/off ratio, and an asymmetric transport pave a new route toward efficient graphene-based field-effect transistors.
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Affiliation(s)
- Aurélien Lherbier
- Institute of Condensed Matter and Nanosciences (IMCN), Université catholique de Louvain (UCL), 1348 Louvain-la-Neuve, Belgium.
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295
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Goncher SJ, Zhao L, Pasupathy AN, Flynn GW. Substrate level control of the local doping in graphene. NANO LETTERS 2013; 13:1386-1392. [PMID: 23461627 DOI: 10.1021/nl3039508] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Graphene exfoliated onto muscovite mica is studied using ultrahigh vacuum scanning tunneling microscopy (UHV-STM) techniques. Mica provides an interesting dielectric substrate interface to measure the properties of graphene due to the ultraflat nature of a cleaved mica surface and the surface electric dipoles it possesses. Flat regions of the mica surface show some surface modulation of the graphene topography (24 pm) due to topographic modulation of the mica surface and full conformation of the graphene to that surface. In addition to these ultraflat regions, plateaus of varying size having been found. A comparison of topographic images and STS measurements show that these plateaus are of two types: one with characteristics of water monolayer formation between the graphene and mica, and the other arising from potassium ions trapped at the interfacial region. Immediately above the water induced plateaus, graphene is insulated from charge doping, while p-type doping is observed in areas adjacent to these water nucleation points. However, above and in the neighborhood of interfacial potassium ions, only n-type doping is observed. Graphene regions above the potassium ions are more strongly n-doped than regions adjacent to these alkali atom plateaus. Furthermore, a direct correlation of these Fermi level shifts with topographic features is seen without the random charge carrier density modulation observed in other dielectric substrates. This suggests a possible route to nanoscopic control of the local electron and hole doping in graphene via specific substrate architecture.
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Affiliation(s)
- Scott J Goncher
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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296
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Impact of Vacancies on Diffusive and Pseudodiffusive Electronic Transport in Graphene. CRYSTALS 2013. [DOI: 10.3390/cryst3020289] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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297
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Borders TL, Fonseca AF, Zhang H, Cho K, Rusinko A. Developing descriptors to predict mechanical properties of nanotubes. J Chem Inf Model 2013; 53:773-82. [PMID: 23452005 DOI: 10.1021/ci300482n] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Descriptors and quantitative structure property relationships (QSPR) were investigated for mechanical property prediction of carbon nanotubes (CNTs). 78 molecular dynamics (MD) simulations were carried out, and 20 descriptors were calculated to build quantitative structure property relationships (QSPRs) for Young's modulus and Poisson's ratio in two separate analyses: vacancy only and vacancy plus methyl functionalization. In the first analysis, C(N2)/C(T) (number of non-sp2 hybridized carbons per the total carbons) and chiral angle were identified as critical descriptors for both Young's modulus and Poisson's ratio. Further analysis and literature findings indicate the effect of chiral angle is negligible at larger CNT radii for both properties. Raman spectroscopy can be used to measure C(N2)/C(T), providing a direct link between experimental and computational results. Poisson's ratio approaches two different limiting values as CNT radii increases: 0.23-0.25 for chiral and armchair CNTs and 0.10 for zigzag CNTs (surface defects <3%). In the second analysis, the critical descriptors were C(N2)/C(T), chiral angle, and M(N)/C(T) (number of methyl groups per total carbons). These results imply new types of defects can be represented as a new descriptor in QSPR models. Finally, results are qualified and quantified against experimental data.
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Affiliation(s)
- Tammie L Borders
- Department of Chemistry, University of North Texas, Denton, Texas 76203, USA.
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298
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Ortmann F, Roche S. Splitting of the zero-energy Landau level and universal dissipative conductivity at critical points in disordered graphene. PHYSICAL REVIEW LETTERS 2013; 110:086602. [PMID: 23473182 DOI: 10.1103/physrevlett.110.086602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 01/09/2013] [Indexed: 06/01/2023]
Abstract
We report on robust features of the longitudinal conductivity (σ(xx)) of the graphene zero-energy Landau level in the presence of disorder and varying magnetic fields. By mixing an Anderson disorder potential with a low density of sublattice impurities, the transition from metallic to insulating states is theoretically explored as a function of Landau-level splitting, using highly efficient real-space methods to compute the Kubo conductivities (both σ(xx) and Hall σ(xy)). As long as valley degeneracy is maintained, the obtained critical conductivity σ(xx) =/~ 1.4e(2)/h is robust upon an increase in disorder (by almost 1 order of magnitude) and magnetic fields ranging from about 2 to 200 T. When the sublattice symmetry is broken, σ(xx) eventually vanishes at the Dirac point owing to localization effects, whereas the critical conductivities of pseudospin-split states (dictating the width of a σ(xy) = 0 plateau) change to σ(xx) =/~ e(2)/h, regardless of the splitting strength, superimposed disorder, or magnetic strength. These findings point towards the nondissipative nature of the quantum Hall effect in disordered graphene in the presence of Landau level splitting.
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Affiliation(s)
- Frank Ortmann
- CIN2 (ICN-CSIC) and Universitat Autónoma de Barcelona, Catalan Institute of Nanotechnology, Campus UAB, 08193 Bellaterra, Spain
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299
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Grüneis A. Synthesis and electronic properties of chemically functionalized graphene on metal surfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:043001. [PMID: 23257769 DOI: 10.1088/0953-8984/25/4/043001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A review on the electronic properties, growth and functionalization of graphene on metals is presented. Starting from the derivation of the electronic properties of an isolated graphene layer using the nearest neighbor tight-binding (TB) approximation for π and σ electrons, the TB model is then extended to third-nearest neighbors and interlayer coupling. The latter is relevant to few-layer graphene and graphite. Next, the conditions under which epitaxial graphene can be obtained by chemical vapor deposition are reviewed with a particular emphasis on the Ni(111) surface. Regarding functionalization, I first discuss the intercalation of monolayer Au into the graphene/Ni(111) interface, which renders graphene quasi-free-standing. The Au intercalated quasi-free-standing graphene is then the basis for chemical functionalization. Functionalization of graphene is classified into covalent, ionic and substitutional functionalization. As archetypical examples for these three possibilities I discuss covalent functionalization by hydrogen, ionic functionalization by alkali metals and substitutional functionalization by nitrogen heteroatoms.
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Affiliation(s)
- Alexander Grüneis
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Wien, Austria.
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300
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Koepke JC, Wood JD, Estrada D, Ong ZY, He KT, Pop E, Lyding JW. Atomic-scale evidence for potential barriers and strong carrier scattering at graphene grain boundaries: a scanning tunneling microscopy study. ACS NANO 2013; 7:75-86. [PMID: 23237026 DOI: 10.1021/nn302064p] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We use scanning tunneling microscopy and spectroscopy to examine the electronic nature of grain boundaries (GBs) in polycrystalline graphene grown by chemical vapor deposition (CVD) on Cu foil and transferred to SiO(2) substrates. We find no preferential orientation angle between grains, and the GBs are continuous across graphene wrinkles and SiO(2) topography. Scanning tunneling spectroscopy shows enhanced empty states tunneling conductance for most of the GBs and a shift toward more n-type behavior compared to the bulk of the graphene. We also observe standing wave patterns adjacent to GBs propagating in a zigzag direction with a decay length of ~1 nm. Fourier analysis of these patterns indicates that backscattering and intervalley scattering are the dominant mechanisms responsible for the mobility reduction in the presence of GBs in CVD-grown graphene.
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Affiliation(s)
- Justin C Koepke
- Department of Electrical & Computer Engineering, University of Illinois, Urbana-Champaign, Illinois 61801, USA.
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