▎ 摘　　要

The interfacial electronic structure of MoO3-x/graphene has been investigated using photoemission spectroscopy. The experimental data showed that upon deposition of MoO3-x, the Fermi level of graphene shifts downward gradually from its Dirac point due to the p-type doping effect. From the Fermi level shift of -0.28 eV, the hole density of graphene was estimated to be 5.44 x 10(12) cm(-2). The formation of surface negative dipole due to electron transfer from graphene to the deposited MoO3-x films increased the sample's work function. The existence of gap states in MoO3-x induced by oxygen vacancies greatly reduced the hole injection barrier at the MoO3-x/graphene interface. (C) 2013 Elsevier Ltd. All rights reserved.