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Zhao N, Song M, Zhang X, Xu W, Liu X. Nanodiamond Coating in Energy and Engineering Fields: Synthesis Methods, Characteristics, and Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2401292. [PMID: 38726946 DOI: 10.1002/smll.202401292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/19/2024] [Indexed: 10/04/2024]
Abstract
Nanodiamonds are metastable allotropes of carbon. Based on their high hardness, chemical inertness, high thermal conductivity, and wide bandgap, nanodiamonds are widely used in energy and engineering applications in the form of coatings, such as mechanical processing, nuclear engineering, semiconductors, etc., particularly focusing on the reinforcement in mechanical performance, corrosion resistance, heat transfer, and electrical behavior. In mechanical performance, nanodiamond coatings can elevate hardness and wear resistance, improve the efficiency of mechanical components, and concomitantly reduce friction, diminish maintenance costs, particularly under high-load conditions. Concerning chemical inertness and corrosion resistance, nanodiamond coatings are gradually becoming the preferred manufacturing material or surface modification material for equipment in harsh environments. As for heat transfer, the extremely high coefficient of thermal conductivity of nanodiamond coatings makes them one of the main surface modification materials for heat exchange equipment. The increase of nucleation sites results in excellent performance of nanodiamond coatings during the boiling heat transfer stage. Additionally, concerning electrical properties, nanodiamond coatings elevate the efficiency of solar cells and fuel cells, and great performance in electrochemical and electrocatalytic is found. This article will briefly describe the application and mechanism analysis of nanodiamonds in the above-mentioned fields.
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Affiliation(s)
- Ningkang Zhao
- College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Meiqi Song
- College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xifang Zhang
- College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wei Xu
- College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaojing Liu
- School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
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Sethy SK, Ficek M, Sankaran KJ, Sain S, Tripathy AR, Gupta S, Ryl J, Sinha Roy S, Tai NH, Bogdanowicz R. Nitrogen-Incorporated Boron-Doped Nanocrystalline Diamond Nanowires for Microplasma Illumination. ACS APPLIED MATERIALS & INTERFACES 2021; 13:55687-55699. [PMID: 34781675 DOI: 10.1021/acsami.1c16507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The origin of nitrogen-incorporated boron-doped nanocrystalline diamond (NB-NCD) nanowires as a function of substrate temperature (Ts) in H2/CH4/B2H6/N2 reactant gases is systematically addressed. Because of Ts, there is a drastic modification in the dimensional structure and microstructure and hence in the several properties of the NB-NCD films. The NB-NCD films grown at low Ts (400 °C) contain faceted diamond grains. The morphology changes to nanosized diamond grains for NB-NCD films grown at 550 °C (or 700 °C). Interestingly, the NB-NCD films grown at 850 °C possess one-dimensional nanowire-like morphological grains. These nanowire-like NB-NCD films possess the co-existence of the sp3-diamond phase and the sp2-graphitic phase, where diamond nanowires are surrounded by sp2-graphitic phases at grain boundaries. The optical emission spectroscopy studies stated that the CN, BH, and C2 species in the plasma are the main factors for the origin of nanowire-like conducting diamond grains and the materialization of graphitic phases at the grain boundaries. Moreover, conductive atomic force microscopy studies reveal that the NB-NCD films grown at 850 °C show a large number of emission sites from the grains and the grain boundaries. While boron doping improved the electrical conductivity of the NCD grains, the nitrogen incorporation eased the generation of graphitic phases at the grain boundaries that afford conducting channels for the electrons, thus achieving a high electrical conductivity for the NB-NCD films grown at 850 °C. The microplasma devices using these nanowire-like NB-NCD films as cathodes display superior plasma illumination properties with a threshold field of 3300 V/μm and plasma current density of 1.04 mA/cm2 with a supplied voltage of 520 V and a lifetime stability of 520 min. The outstanding plasma illumination characteristics of these conducting nanowire-like NB-NCD films make them appropriate as cathodes and pave the way for the utilization of these materials in various microplasma device applications.
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Affiliation(s)
- Salila Kumar Sethy
- CSIR-Institute of Minerals and Materials Technology, Bhubaneswar 751013, India
| | - Mateusz Ficek
- Department of Metrology and Optoelectronics, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, 80-233 Gdansk, Poland
| | | | - Sourav Sain
- Department of Physics, School of Natural Sciences, Shiv Nadar University, Gautam Buddha Nagar, Uttar Pradesh 201314, India
| | - Anupam Ruturaj Tripathy
- Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China
| | - Shivam Gupta
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China
| | - Jacek Ryl
- Department of Electrochemistry, Corrosion and Materials Engineering, Faculty of Chemistry, Gdansk University of Technology, 80-233 Gdansk, Poland
| | - Susanta Sinha Roy
- Department of Physics, School of Natural Sciences, Shiv Nadar University, Gautam Buddha Nagar, Uttar Pradesh 201314, India
| | - Nyan-Hwa Tai
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China
| | - Robert Bogdanowicz
- Department of Metrology and Optoelectronics, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, 80-233 Gdansk, Poland
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Sankaran KJ, Yeh CJ, Hsieh PY, Pobedinskas P, Kunuku S, Leou KC, Tai NH, Lin IN, Haenen K. Origin of Conductive Nanocrystalline Diamond Nanoneedles for Optoelectronic Applications. ACS APPLIED MATERIALS & INTERFACES 2019; 11:25388-25398. [PMID: 31260239 DOI: 10.1021/acsami.9b05469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Microstructural evolution of nanocrystalline diamond (NCD) nanoneedles owing to the addition of methane and nitrogen in the reactant gases is systematically addressed. It has been determined that varying the concentration of CH4 in the CH4/H2/N2 plasma is significant to tailor the morphology and microstructure of NCD films. While NCD films grown with 1% CH4 in a CH4/H2/N2 (3%) plasma contain large diamond grains, the microstructure changed considerably for NCD films grown using 5% (or 10%) CH4, ensuing in nanosized diamond grains. For 15% CH4-grown NCD films, a well-defined nanoneedle structure evolves. These NCD nanoneedle films contain sp3 phase diamond, sheathed with sp2-bonded graphitic phases, achieving a low resistivity of 90 Ω cm and enhanced field electron emission (FEE) properties, namely, a low turn-on field of 4.3 V/μm with a high FEE current density of 3.3 mA/cm2 (at an applied field of 8.6 V/μm) and a significant field enhancement factor of 3865. Furthermore, a microplasma device utilizing NCD nanoneedle films as cathodes can trigger a gas breakdown at a low threshold field of 3600 V/cm attaining a high plasma illumination current density of 1.14 mA/cm2 at an applied voltage of 500 V, and a high plasma lifetime stability of 881 min is evidenced. The optical emission spectroscopy studies suggest that the C2, CN, and CH species in the growing plasma are the major causes for the observed microstructural evolution in the NCD films. However, the increase in substrate temperature to ∼780 °C due to the incorporation of 15% CH4 in the CH4/H2/N2 plasma is the key driver resulting in the origin of nanoneedles in NCD films. The outstanding optoelectronic characteristics of these nanoneedle films make them suitable as cathodes in high-brightness display panels.
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Affiliation(s)
| | | | | | - Paulius Pobedinskas
- Institute for Materials Research (IMO) , Hasselt University , Diepenbeek 3590 , Belgium
- IMOMEC, IMEC vzw , Diepenbeek 3590 , Belgium
| | | | | | | | - I-Nan Lin
- Department of Physics , Tamkang University , Tamsui 251 , Taiwan , Republic of China
| | - Ken Haenen
- Institute for Materials Research (IMO) , Hasselt University , Diepenbeek 3590 , Belgium
- IMOMEC, IMEC vzw , Diepenbeek 3590 , Belgium
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Shellaiah M, Chen YC, Simon T, Li LC, Sun KW, Ko FH. Effect of Metal Ions on Hybrid Graphite-Diamond Nanowire Growth: Conductivity Measurements from a Single Nanowire Device. NANOMATERIALS 2019; 9:nano9030415. [PMID: 30862083 PMCID: PMC6473948 DOI: 10.3390/nano9030415] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/04/2019] [Accepted: 03/07/2019] [Indexed: 12/11/2022]
Abstract
Novel Cd2+ ions mediated reproducible hybrid graphite-diamond nanowire (G-DNWs; Cd2+-NDS1 NW) growth from 4-Amino-5-phenyl-4H-1,2,4-triazole-3-thiol (S1) functionalized diamond nanoparticles (NDS1) via supramolecular assembly is reported and demonstrated through TEM and AFM images. FTIR, EDX and XPS studies reveal the supramolecular coordination between functional units of NDS1 and Cd2+ ions towards NWs growth. Investigations of XPS, XRD and Raman data show the covering of graphite sheath over DNWs. Moreover, HR-TEM studies on Cd2+-NDS1 NW confirm the coexistence of less perfect sp2 graphite layer and sp3 diamond carbon along with impurity channels and flatten surface morphology. Possible mechanisms behind the G-DNWs growth are proposed and clarified. Subsequently, conductivity of the as-grown G-DNWs is determined through the fabrication of a single Cd2+-NDS1 NW device, in which the G-DNW portion L2 demonstrates a better conductivity of 2.31 × 10−4 mS/cm. In addition, we investigate the temperature-dependent carrier transport mechanisms and the corresponding activation energy in details. Finally, comparisons in electrical resistivities with other carbon-based materials are made to validate the importance of our conductivity measurements.
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Affiliation(s)
- Muthaiah Shellaiah
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan.
| | - Ying-Chou Chen
- Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan.
| | - Turibius Simon
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 300, Taiwan.
| | - Liang-Chen Li
- Center for Nano Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan.
| | - Kien Wen Sun
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan.
- Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan.
- Center for Nano Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan.
| | - Fu-Hsiang Ko
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 300, Taiwan.
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Deshmukh S, Sankaran KJ, Korneychuk S, Verbeeck J, Mclaughlin J, Haenen K, Roy SS. Nanostructured nitrogen doped diamond for the detection of toxic metal ions. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.07.067] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Shellaiah M, Chen TH, Simon T, Li LC, Sun KW, Ko FH. An Affordable Wet Chemical Route to Grow Conducting Hybrid Graphite-Diamond Nanowires: Demonstration by A Single Nanowire Device. Sci Rep 2017; 7:11243. [PMID: 28894276 PMCID: PMC5593905 DOI: 10.1038/s41598-017-11741-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 08/30/2017] [Indexed: 11/09/2022] Open
Abstract
We report an affordable wet chemical route for the reproducible hybrid graphite-diamond nanowires (G-DNWs) growth from cysteamine functionalized diamond nanoparticles (ND-Cys) via pH induced self-assembly, which has been visualized through SEM and TEM images. Interestingly, the mechanistic aspects behind that self-assembly directed G-DNWs formation was discussed in details. Notably, above self-assembly was validated by AFM and TEM data. Further interrogations by XRD and Raman data were revealed the possible graphite sheath wrapping over DNWs. Moreover, the HR-TEM studies also verified the coexistence of less perfect sp2 graphite layer wrapped over the sp3 diamond carbon and the impurity channels as well. Very importantly, conductivity of hybrid G-DNWs was verified via fabrication of a single G-DNW. Wherein, the better conductivity of G-DNW portion L2 was found as 2.4 ± 1.92 × 10−6 mS/cm and revealed its effective applicability in near future. In addition to note, temperature dependent carrier transport mechanisms and activation energy calculations were reported in details in this work. Ultimately, to demonstrate the importance of our conductivity measurements, the possible mechanism behind the electrical transport and the comparative account on electrical resistivities of carbon based materials were provided.
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Affiliation(s)
- Muthaiah Shellaiah
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Tin Hao Chen
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Turibius Simon
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Liang-Chen Li
- Center for Nano Science and Technology, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Kien Wen Sun
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu, 300, Taiwan. .,Center for Nano Science and Technology, National Chiao Tung University, Hsinchu, 300, Taiwan. .,Department of Electronics Engineering, National Chiao Tung University, Hsinchu, 300, Taiwan.
| | - Fu-Hsiang Ko
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, 300, Taiwan
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Chang TH, Hsieh PY, Kunuku S, Lou SC, Manoharan D, Leou KC, Lin IN, Tai NH. High Stability Electron Field Emitters Synthesized via the Combination of Carbon Nanotubes and N₂-Plasma Grown Ultrananocrystalline Diamond Films. ACS APPLIED MATERIALS & INTERFACES 2015; 7:27526-27538. [PMID: 26600097 DOI: 10.1021/acsami.5b09778] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An electron field emitter with superior electron field emission (EFE) properties and improved lifetime stability is being demonstrated via the combination of carbon nanotubes and the CH4/N2 plasma grown ultrananocrystalline diamond (N-UNCD) films. The resistance of the carbon nanotubes to plasma ion bombardment is improved by the formation of carbon nanocones on the side walls of the carbon nanotubes, thus forming strengthened carbon nanotubes (s-CNTs). The N-UNCD films can thus be grown on s-CNTs, forming N-UNCD/s-CNTs carbon nanocomposite materials. The N-UNCD/s-CNTs films possess good conductivity of σ = 237 S/cm and marvelous EFE properties, such as low turn-on field of (E0) = 3.58 V/μm with large EFE current density of (J(e)) = 1.86 mA/cm(2) at an applied field of 6.0 V/μm. Moreover, the EFE emitters can be operated under 0.19 mA/cm(2) for more than 350 min without showing any sign of degradation. Such a superior EFE property along with high robustness characteristic of these combination of materials are not attainable with neither N-UNCD films nor s-CNTs films alone. Transmission electron microscopic investigations indicated that the N-UNCD films contain needle-like diamond grains encased in a few layers of nanographitic phase, which enhanced markedly the transport of electrons in the N-UNCD films. Moreover, the needle-like diamond grains were nucleated from the s-CNTs without the necessity of forming the interlayer that facilitate the transport of electrons crossing the diamond-to-Si interface. Both these factors contributed to the enhanced EFE behavior of the N-UNCD/s-CNTs films.
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Affiliation(s)
- Ting-Hsun Chang
- Department of Materials Science and Engineering, National Tsing-Hua University , Hsinchu 300, Taiwan, R.O.C
| | - Ping-Yen Hsieh
- Department of Materials Science and Engineering, National Tsing-Hua University , Hsinchu 300, Taiwan, R.O.C
| | - Srinivasu Kunuku
- Department of Engineering and System Science, National Tsing-Hua University , Hsinchu 300, Taiwan, R.O.C
| | - Shiu-Cheng Lou
- Center for Measurement Standards, Industrial Technology Research Institute , Hsinchu 300, Taiwan, R.O.C
| | - Divinah Manoharan
- Department of Physics, Tamkang University , New Taipei City 251, Taiwan, R.O.C
| | - Keh-Chyang Leou
- Department of Engineering and System Science, National Tsing-Hua University , Hsinchu 300, Taiwan, R.O.C
| | - I-Nan Lin
- Department of Physics, Tamkang University , New Taipei City 251, Taiwan, R.O.C
| | - Nyan-Hwa Tai
- Department of Materials Science and Engineering, National Tsing-Hua University , Hsinchu 300, Taiwan, R.O.C
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Yu Y, Wu L, Zhi J. Diamant-Nanodrähte: Herstellung, Struktur, Eigenschaften und Anwendungen. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201310803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mangolini F, McClimon JB, Rose F, Carpick RW. Accounting for Nanometer-Thick Adventitious Carbon Contamination in X-ray Absorption Spectra of Carbon-Based Materials. Anal Chem 2014; 86:12258-65. [DOI: 10.1021/ac503409c] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Filippo Mangolini
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - J. Brandon McClimon
- Department
of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Franck Rose
- HGST, a Western Digital Company, San
Jose, California 95135, United States
| | - Robert W. Carpick
- Department
of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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Yu Y, Wu L, Zhi J. Diamond nanowires: fabrication, structure, properties, and applications. Angew Chem Int Ed Engl 2014; 53:14326-51. [PMID: 25376154 DOI: 10.1002/anie.201310803] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Indexed: 11/12/2022]
Abstract
C(sp(3) )C-bonded diamond nanowires are wide band gap semiconductors that exhibit a combination of superior properties such as negative electron affinity, chemical inertness, high Young's modulus, the highest hardness, and room-temperature thermal conductivity. The creation of 1D diamond nanowires with their giant surface-to-volume ratio enhancements makes it possible to control and enhance the fundamental properties of diamond. Although theoretical comparisons with carbon nanotubes have shown that diamond nanowires are energetically and mechanically viable structures, reproducibly synthesizing the crystalline diamond nanowires has remained challenging. We present a comprehensive, up-to-date review of diamond nanowires, including a discussion of their synthesis along with their structures, properties, and applications.
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Affiliation(s)
- Yuan Yu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 (P.R. China)
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Lin Y, Su D. Fabrication of nitrogen-modified annealed nanodiamond with improved catalytic activity. ACS NANO 2014; 8:7823-7833. [PMID: 25036282 DOI: 10.1021/nn501286v] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Annealed ultradispersed nanodiamond (ADD) with sp(2) curved concentric graphitic shells is an interesting hybrid material consisting of the remarkable surface properties of graphene-based nanomaterials and the intrinsic properties of a diamond core. In this case, based on its specific properties and surface oxygen functional groups, nitrogen-modified ADD powders have been tunably synthesized via three different preparation methods in a calcination treatment process. The detailed formation and dynamic behaviors of the nitrogen species on the modified ADD during the preparation process are revealed by elemental analysis, X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption. Moreover, we study the catalytic performance on the metal-free nitrogen-modified ADD catalysts by means of selective oxidation of benzylic alcohols as a probe reaction. The results indicate that the modified ADD catalysts exhibit a higher catalytic activity than pristine ADD. By correlating XPS data with catalytic measurements, we conclude that the pyridinic nitrogen species plays a pivotal role in the catalytic reaction. Our work provides valuable information on the design of modified carbon materials with more excellent properties.
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Affiliation(s)
- Yangming Lin
- School of Chemistry and Materials Science, University of Science and Technology of China , Hefei 230001, People's Republic of China
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Panda K, Sankaran KJ, Panigrahi BK, Tai NH, Lin IN. Direct observation and mechanism for enhanced electron emission in hydrogen plasma-treated diamond nanowire films. ACS APPLIED MATERIALS & INTERFACES 2014; 6:8531-8541. [PMID: 24824342 DOI: 10.1021/am501398s] [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 effect of hydrogen plasma treatment on the electrical conductivity and electron field emission (EFE) properties for diamond nanowire (DNW) films were systematically investigated. The DNW films were deposited on silicon substrate by N2-based microwave plasma-enhanced chemical vapor deposition process. Transmission electron microscopy depicted that DNW films mainly consist of wirelike diamond nanocrystals encased in a nanographitic sheath, which formed conduction channels for efficient electron transport and hence lead to excellent electrical conductivity and EFE properties for these films. Hydrogen plasma treatment initially enhanced the electrical conductivity and EFE properties of DNW films and then degraded with an increase in treatment time. Scanning tunneling spectroscopy in current imaging tunneling spectroscopy mode clearly shows significant increase in local emission sites in 10 min hydrogen plasma treated diamond nanowire (DNW10) films as compared to the pristine films that is ascribed to the formation of graphitic phase around the DNWs due to the hydrogen plasma treatment process. The degradation in EFE properties of extended (15 min) hydrogen plasma-treated DNW films was explained by the removal of nanographitic phase surrounding the DNWs. The EFE process of DNW10 films can be turned on at a low field of 4.2 V/μm and achieved a high EFE current density of 5.1 mA/cm(2) at an applied field of 8.5 V/μm. Moreover, DNW10 films with high electrical conductivity of 216 (Ω cm)(-1) overwhelm that of other kinds of UNCD films and will create a remarkable impact to diamond-based electronics.
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Affiliation(s)
- Kalpataru Panda
- Graduate School of Engineering, Osaka University , 2-1 Yamada-Oka, 565-0871 Suita, Osaka, Japan
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