Electronic structure and field emission properties of in situ potassium-doped single-walled carbon nanotubes

Abstract

In situ potassium (K)-doped single-walled carbon nanotube (SWCNT) was synthesized using a hydrogen arc-discharge method. X-ray photoelectron spectroscopy analysis showed that the K-doped SWCNTs consisted of 0.12% K mass composition. The K-doped SWCNTs showed the lower turn-on electric field of 2.0V∕μm at a current density of 10−9A∕cm2 and the higher emission current density of 3.0mA∕cm2 at an applied field of 4.6V∕μm compared with the undoped SWCNTs. The improved field emission performance of K-doped SWCNTs was mainly attributed to the decreased work function and the increased density of state near the Fermi energy.