Improvement of field-emission properties of screen printed carbon nanotube films via argon plasma treatment

Abstract

In this paper, we describe an effective surface treatment to improve the field emission site density. The carbon nanotube (CNT) films fabricated by a screen printing process have been exposed to Ar plasma for varying durations and their field emission characteristics have been measured. The CNT films, after applying an Ar plasma treatment, have excellent field emission characteristics with very high emission current and low threshold fields. Scanning electron microscopy showed the contamination removal from the surface of the CNT films, and transmission electron microscopy showed the structural modification of the CNT walls after exposure to Ar plasma. Raman results showed that the particles generated by the deformation of the CNT structure had characteristics of both single-wall carbon nanotubes (SWCNTs) and multiwall carbon nanotubes (MWCNTs). We attribute improvement of field emission properties to the changes of the geometrical structure of the local emission region in MWCNTs. (C) 2006 The Electrochemical Society.