Graphene/gallium arsenide-based Schottky junction solar cells

Chemical-vapor-deposited single- and bi-layer graphene sheets have been transferred onto n-type GaAs substrates. The rectifying characteristics and photovoltaic behaviors of graphene/GaAs junctions have been systematically investigated. The graphene sheets can be combined with the underlying n-type GaAs substrates to form Schottky junctions. For bilayer graphene, the Schottky junction shows photovoltaic effects with the open-circuit voltage of 0.65 V and the short-circuit current density of 10.03 mA/cm2, yielding a power conversion efficiency of 1.95%, which are superior to single-layer one. Such performance parameters are comparable to those of other pristine graphene/semiconductor junction-based devices.