La B 6 tip-modified multiwalled carbon nanotube as high quality field emission electron source

An effective field emitter has been developed by modifying an individual multiwalled carbon nanotube (MWCNT) tip with LaB6. The modified emitter possesses the merits of both the MWCNT and LaB6, which presents a significant low turn-on voltage, good emission properties, and long lifetime. As a result, a total current of 70μA has been reached at a very low electric field of only 1.2V∕μm for an individual modified MWCNT emitter, which is also expected to have advantages of high brightness and coherence, clearly indicating great promise for practical applications such as electron guns or cathodes for field emission flat panel display.