Potential barrier of Graphene edges

TL;DR

This study investigates the electronic properties and potential barriers of graphene edges with different terminations, revealing how edge chemistry influences work function and charge distribution, which are crucial for electronic applications.

Contribution

It provides detailed calculations of density of states, charge distribution, and work function for various graphene edge terminations, highlighting the impact of chemical groups on electronic properties.

Findings

OH-terminated zigzag edge has the lowest work function of 3.76 eV

O-terminated zigzag edge has the highest work function of 7.74 eV

angle-dependent potential barriers are modeled and explained by charge distribution

Abstract

We calculated row resolved density of states, charge distribution and work function of graphene's zigzag and armchair edge (either clean or terminated alternatively with H, O or OH group). The zigzag edge saturated via OH group has the lowest work function of 3.76 eV, while the zigzag edge terminated via O has the highest work function of 7.74 eV. The angle-dependent potential barrier on the edge is fitted to a multi-pole model and is explained by the charge distribution.