采用铬酸溶液对碳纳米管进行后处理,旨在修饰碳纳米管的表面形态及改变碳纳米管的表面结构,进一步增强碳纳米管的场发射特性.铬酸溶液后处理与传统以硝酸后处理的厅法不同之处在于,铬酸溶液可以更有效率地与非品质碳及碳纳米管发生化学反应.可以预期碳纳米管经过铬酸溶液处理后,碳纳米管的表而形态、化学组成及场发射特性会产生很大的变化.场发射的数据显示,经铬酸溶液处理20 min的碳纳米管场发射电流比未经过铬酸溶液处理的场发射电流有明显的增加.然而,长时间的铬酸溶液处理也会降低碳纳米管场发射特性.经铬酸溶液处理20min的碳纳米管场发射电流增强原因主要为适度的铬酸溶液处理可以改变碳纳米管的表面形态,使碳管的表面密度增大、场发射功函数降低.但过长时间的铬酸溶液后处理,又会造成碳纳米管数目减少及表面结构受到损害,导致碳纳米管场发射特性变差.
A simple method is described to functionalize the surface and to modify the structures of multi-walled carbon nanotubes (MWCNTs) grown on silicon substrates using chromium trioxide (CrO3) solution. Unlike nitric acid (HNO3) used in the conventional post-treatment for MWCNTs, the chemical reaction with CrO3 involves amorphous carbon and the carbon nanotubes themselves. It is expected that the surface morphology, chemical composition, and field emission of MWCNTs should be significantly changed after CrO3 solution treatment. The results showed that after 20 min of CrO3 solution treatment, the emission currents were enhanced compared with the as-grown MWCNTs. However, extended treatment over 20 min was found to degrade the field emission properties of the film. The enhancement in field emission after 20 min of CrO3 solution treatment can be ascribed to the modification of surface morphology, the increase in surface density of MWCNTs, and the lowering of the work function. Prolonged CrO3 treatment dissolves MWCNTs and thus results in a decrease in field emission.
参考文献
| [1] | Iijima S .Helical microtubulas of graphitic carbon[J].Nature,1991,354:56-58. |
| [2] | de Heer W A;Chatelain A;Ugarte D .Aligned carnotube films:production and electronic properties[J].Science,1995,270(5293):1179-1180. |
| [3] | Kenneth A. Dean;Babu R. Chalamala .The environmental stability of field emission from single-walled carbon nanotubes[J].Applied physics letters,1999(19):3017-3019. |
| [4] | Jean-Marc Bonard;Hannes Kind;Thomas Stockli .Field emission from carbon nanotubes: the first five years[J].Solid-State Electronics,2001(6):893-914. |
| [5] | P.X.Hou;S.Bai;Q.H.Yang;C.Liu;H.M.Cheng .Multi-step purification of carbon nanotubes[J].Carbon: An International Journal Sponsored by the American Carbon Society,2002(1):81-85. |
| [6] | SaitoT;Matsushige K;Tanaka K .Chemical treatment and modification of multi-walled carbon nanotubes[J].PHYSICA B,2002,323:280-283. |
| [7] | Ultraviolet laser treatment of multiwall carbon nanotubes grown at low temperature[J].Applied physics letters,2003(10):1607-1609. |
| [8] | Ke Yu;Ziqiang Zhu;Yongsheng Zhang;Qiong Li;Weiming Wang;Laiqiang Luo;Xianwen Yu;Honglei Ma;Zhenwen Li;Tao Feng .Change of surface morphology and field emission property of carbon nanotube films treated using a hydrogen plasma[J].Applied Surface Science: A Journal Devoted to the Properties of Interfaces in Relation to the Synthesis and Behaviour of Materials,2004(1/4):380-388. |
| [9] | Jun Xu;Xiaohui Huang;Zhifeing Li;Wei Li;Kunji Chen .The effect of hydrogen plasma chemical annealing on electron field emission of amorphous carbon films[J].Diamond and Related Materials,2003(10/11):2016-2019. |
| [10] | GUO Ping-sheng,SUN Zhuo,ZHENG Zhi-hao.Post-treatment method for improving field emission from carbon nanotubes/nanofibers[J].光电子快报（英文版）,2006(04):252-255. |
| [11] | Y. Liu;L. Liu;P. Liu .Plasma etching carbon nanotube arrays and the field emission properties[J].Diamond and Related Materials,2004(9):1609-1613. |
| [12] | Hamwi A.;Bonnamy S.;Beguin F.;Alvergnat H. .FLUORINATION OF CARBON NANOTUBES[J].Carbon: An International Journal Sponsored by the American Carbon Society,1997(6):723-728. |
| [13] | P. Petit;C. Mathis;C. Journet;P. Bernier .Tuning and monitoring the electronic structure of carbon nanotubes[J].Chemical Physics Letters,1999(5/6):370-374. |
| [14] | Kazaoui S.;Jacquemin R.;Kataura H.;Achiba Y.;Minami N. .Amphoteric doping of single-wall carbon-nanotube thin films as probed by optical absorption spectroscopy[J].Physical Review.B.Condensed Matter,1999(19):13339-13342. |
| [15] | Mittal J.;Allouche H.;Stephan O.;Monthioux M. .Room temperature filling of single-wall carbon nanotubes with chromium oxide in open air[J].Chemical Physics Letters,2001(5-6):311-318. |
| [16] | Dresselhaus MS.;Dresselhaus G. .Intercalation compounds of graphite[J].Advances in physics,2002(1):1-186. |
| [17] | Lee YH.;Kim DH.;Ahn JH.;Ju BK.;Jang YT. .Realization of gated field emitters for electrophotonic applications using carbon nanotube line emitters directly grown into submicrometer holes[J].Advanced Materials,2001(7):479-482. |
| [18] | Padmakar D. Kichambare;Dali Qian;Elizabeth C. Dickey;Craig A. Grimes .Thin film metallic catalyst coatings for the growth of multiwalled carbon nanotubes by pyrolysis of xylene[J].Carbon: An International Journal Sponsored by the American Carbon Society,2002(11):1903-1909. |
| [19] | 李新海,杨占红,陈志国,王红强,李添宝,沈宁一,李晶.炭纳米管的提纯-重铬酸钾氧化法[J].新型炭材料,1999(03):32-36. |
| [20] | Sheng-Chin Kung;Kuo Chu Hwang;I. Nan Lin .Oxygen and ozone oxidation-enhanced field emission of carbon nanotubes[J].Applied physics letters,2002(25):4819-4821. |
| [21] | C. Y. Zhi;X. D. Bai;E. G. Wang .Enhanced field emission from carbon nanotubes by hydrogen plasma treatment[J].Applied physics letters,2002(9):1690-1692. |
| [22] | Ahn K S;Kim J S;Kim C O et al.Non-reactive ff treatment of multiwall carbon nanotube with inert argon plasma for enhanced field emission[J].CARBON,2003,41:2481-2485. |
| [23] | Kawabata A;Ota K;Matsuura T et al.Improvement of field emission characteristics by fabricating aligned open-edged particle-free carbon nanotubes[J].Japanese Journal of Applied Physics,2002,41(12A):L1363-L1365. |
| [24] | Eklund PC.;Jishi RA.;Holden JM. .VIBRATIONAL MODES OF CARBON NANOTUBES - SPECTROSCOPY AND THEORY[J].Carbon: An International Journal Sponsored by the American Carbon Society,1995(7):959-972. |
| [25] | Chakrapani N.;Curran S.;Wei BQ.;Ajayan PM.;Carrillo A.;Kane RS. .Spectral fingerprinting of structural defects in plasma-treated carbon nanotubes[J].Journal of Materials Research,2003(10):2515-2521. |
| [26] | L. Nilsson;O. Groening;C. Emmenegger .Scanning field emission from patterned carbon nanotube films[J].Applied physics letters,2000(15):2071-2073. |
| [27] | Rinzler AG;Hafner JH;Nikolaev P;Lou L;Kim SG;Tomanek D .UNRAVELING NANOTUBES - FIELD EMISSION FROM AN ATOMIC WIRE[J].Science,1995(5230):1550-1553. |
| [28] | Kenneth A. Dean;Paul von Allmen;Babu R. Chalamala .Three behavioral states observed in field emission from single-walled carbon nanotubes[J].Journal of Vacuum Science & Technology, B. Microelectronics and Nanometer Structures: Processing, Measurement and Phenomena,1999(5):1959-1969. |
| [29] | Carroll DL;Redlich P;Ajayan PM;Charlier JC;Blase X;DeVita A;Car R;CLEMSON UNIV DEPT PHYS & ASTRON CLEMSON SC 29634.;RENSSELAER POLYTECH INST DEPT MAT SCI & ENGN TROY NY 12180.;UNIV CATHOLIQUE LOUVAIN UNITE PCPM B-1348 LOUVAIN BELGIUM. .Electronic structure and localized states at carbon nanotube tips[J].Physical review letters,1997(14):2811-2814. |
| [30] | Zhou G.;Gu BL.;Duan WH. .Electronic structure and field-emission characteristics of open-ended single-walled carbon nanotubes - art. no. 095504[J].Physical review letters,2001(9):5504-0. |
| [31] | Bonard J M;Maier F;St cklioT et al.Field emission properties of multiwalled carbon nanotubes[J].Ultramicroscopy,1998,73(09):7-15. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%