Comparative Study of Field Electron Emission from Single-Walled Carbon Nanotube and Multi-Walled Carbon Nanotube Mounted on Tungsten

Abstract

Field Electron Emission (FEE) from Single-Walled Carbon Nanotubes (SWCNTs) and Multi-Walled Carbon Nanotubes (MWCNTs) mounted on blunt tungsten tip has been investigated to make sure that FEE comes from the CNTs. The FEE properties were studied using Field Emission Microscope (FEM), where the distance between the emitter and screen was fixed at ~10 mm and the system was evacuated to (~10^-9 mbar). The emitters were prepared during two stages, with the first one being electrolytically etching the tungsten (W) wire of (0.1 mm diameter) in 2 mol of NaOH, while the second stage involves fixing the CNTs on the etched tungsten. Current-voltage (I-V) measurements were recorded and presented in the most common way as (I-V) plot with its related FowlerNordheim (FN) plot. It has been found that SWCNT samples have several advantages over MWCNT samples, such as the field electron emission having been initiated at lower applied voltage values and maintaining emitting electrons at lower applied voltage values, but MWCNTs emitted higher current values compared to SWCNTs.

Keywords: Field Electron Emission, SWCNTs, MWCNTs.