@article {16497, title = {Single-walled carbon nanotube thermionic electron emitters with dense, efficient and reproducible electron emission}, journal = {Nanoscale}, volume = {9}, year = {2017}, pages = {17814 - 17820}, abstract = {Thermionic electron emitters have recently been scaled down to the microscale using microfabrication technologies and graphene as the filament. While possessing several advantages over field emitters, graphene-based thermionic micro-emitters still exhibit low emission current density and efficiency. Here, we report nanoscale thermionic electron emitters (NTEEs) fabricated using microfabrication technologies and single-walled carbon nanotubes (SWCNTs), the thinnest conducting filament we can use. The SWCNT NTEEs exhibit an emission current density as high as 0.45 {\texttimes} 105 A cm-2, which is superior to that of traditional thermionic emitters and five orders of magnitude higher than that of graphene-based thermionic emitters. The emission characteristics of SWCNT NTEEs are found to strongly depend on the electrical properties of the SWCNTs, with metallic SWCNT NTEEs showing a substantially lower turn-on voltage and more reproducible emission performances than those based on semiconducting SWCNTs. Our results indicate that SWCNT NTEEs are promising for electron source applications}, url = {http://pubs.rsc.org/en/content/articlelanding/2017/nr/c7nr05388f$\#$!divAbstract}, author = {Yuwei Wang and Wu, Gongtao and Li Xiang and Mengmeng Xiao and Zhiwei Li and Gao, Song and Chen, Qing and X* Wei} }