The exchange-correlation potential correction to the vacuum potential   barrier of graphene edge
  We investigated the vacuum potential barriers of various graphene edges terminated with hydrogen, oxygen, hydroxyl group and ether group respectively. It is found that the exchange-correlation potential correction is significant to the edge structures with electronegativity higher than carbon. The correction leads to the local work function decreased by more than 1. eV for the O terminated edge, while the local work function of H and OH terminated edges remain unchanged. 
Weiliang Wang, Junwen Shao and Zhibing Li
cond-mat.mtrl-sci cond-mat.mes-hall