Adsorbate-enhanced field-emission from single-walled carbon nanotubes: a comparative first-principles study

TL;DR

This study uses first-principles calculations to compare how different adsorbates affect the field-emission properties of single-walled carbon nanotubes, revealing significant work function reduction and emission enhancement.

Contribution

It provides a detailed ab-initio comparison of various adsorbates' effects on nanotube emission, highlighting mechanisms for performance improvement.

Findings

Adsorbates reduce work function by up to 1.3 eV.

Field-emission current increases by up to two orders of magnitude.

Electron cloud localization occurs near adsorbates under high electric fields.

Abstract

We report a comparative ab-initio study of different types of adsorbates and their adsorption mechanism on the field-emission performance of single-walled carbon nanotubes by analyzing electrical properties and transport characteristics and considering the thermal stability of the adsorbed structure. Adsorbates were found to reduce the work function by up to 1.3 eV, enhance tunneling near the carbon nanotube tip, and increase the field-emission current by as much as two orders of magnitude. A significant localization of the electron cloud was also observed near the adsorbates under a high applied electric field .