首页 | 本学科首页   官方微博 | 高级检索  
     


Fabrication of multi-emitter array of CNT for enhancement of current density
Authors:Vijay Chouhan  Tsuneyuki NoguchiShigeki Kato
Affiliation:a Department of Accelerator Science, The Graduate University for Advanced Studies, 1-1 Oho, Tsukuba, Ibaraki, Japan
b High Energy Accelerator Research Organization—KEK, 1-1 Oho, Tsukuba, Ibaraki, Japan
Abstract:We studied and compared field emission properties of two kinds of emitters of randomly oriented multi-wall carbon nanotubes (MWNTs), viz. continuous film emitter (CFE) and multi-emitter array (MEA). The CFE has a continuous film of MWNTs while the MEA consists of many equidistant small circular emitters. Both types of emitters were prepared by dispersing MWNTs over a titanium (Ti) film (for CFEs) or Ti circular islands (for MEAs) deposited on tantalum (Ta) followed by rooting of MWNTs into the Ti film or the Ti islands at high temperature. Emission properties of both types of emitters were analyzed with changing their emission areas. In case of the CFEs, current density decreased with an increase in emission area whereas consistent current densities were achieved from MEAs with different emission areas. In other words, the total emission current was achieved in proportion to the emission area in the case of MEAs. Additionally a high current density of 22 A/cm2 was achieved at an electric field of 8 V/μm from MEAs, which was far better than that obtained from CFEs. The high current density in MEAs was attributed to edge effect, in which higher emission current is achieved from the edge of film emitter. The results indicate that the field emission characteristics can be greatly improved if a cathode contains many small equidistant circular emitters instead of a continuous film. The outstanding stability of the CFE and the MEA has been demonstrated for 2100 and 1007 h, respectively.
Keywords:Multi-wall carbon nanotube  Field emission  Edge effect
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号