▎ 摘　　要

We present a comparative study of the environmental and thermal stability of graphene charge transfer doping using molybdenum-trioxide (MoO3), vanadium-pentoxide (V2O5) and tungsten-trioxide (WO3). Our results show that all these metal oxides allow a strong and stable p-type doping of graphene, as well as functioning as effective hole-injection layers for highly efficient organic light emitting diodes.