Evaporation of carbon nanotubes during electron field emission

Abstract

Extracting large field-emission currents from individual single-walled carbon nanotubes degrades their current–voltage behavior and changes the nanotube structure. Field-emission microscopy observations and field-emission current–voltage measurements revealed behavior characteristic of local heating, followed by thermally assisted field evaporation of the atoms on the end of the nanotube, and subsequent restructuring of the cap. Field evaporation of carbon was found to result in reduction of the length of the tube without catastrophic arcing events. This process defines the upper limit for the field-emission current that can be obtained from an individual single-walled nanotube.