Graphene with the secondary amine-terminated zigzag edge as a line electron emitter

TL;DR

This paper demonstrates through ab initio calculations that secondary amine-terminated zigzag graphene edges exhibit an exceptionally low vacuum barrier height and flat band edge states, making them promising for highly coherent line electron emission.

Contribution

It introduces a novel edge structure of graphene with secondary amine termination that significantly enhances electron emission properties compared to previous configurations.

Findings

Barrier height of 2.30 eV on zigzag edges

Flat band edge states dominate emission

Potential for highly coherent emission current

Abstract

An extraordinary low vacuum barrier height of 2.30 eV has been found on the zigzag-edge of graphene terminated with the secondary amine via the ab initio calculation. This edge structure has a flat band of edge states attached to the gamma point where the transversal kinetic energy is vanishing. We show that the field electron emission is dominated by the flat band. The edge states pin the Fermi level to a constant, leading to an extremely narrow emission energy width. The graphene with such edge is a promising line field electron emitter that can produce highly coherent emission current.