Influences of the surface reactions on the field emission from multiwall carbon nanotubes

Abstract

Field emission characteristics from multiwall carbon nanotubes were studied under various gas environments. The experiments on field emission revealed several surface reactions under high-vacuum operating conditions. The Fowler–Nordheim (F–N) analysis showed a field emission regime dominated by the surface adsorbents, operational modes, and nanotube types. The emission-assisted surface reaction process, which enhances the gas adsorptions in low current regimes and desorption under high currents, plays a key role for the observed deviation from the F–N results. Different gas exposures suggested that the nanotube-H2O and nanotube-H2 reactions cause the current increase in the low emission range.