Potential barrier of Graphene edges

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.Comment: 16 pages, 8 figures. Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in (J. Appl. Phys. 109 (2011) 114308) and may be found at (http://link.aip.org/link/?JAP/109/114308