Highly oriented CuInS2 thin films on graphene electrodes for solar-cell applications

Highly oriented CuInS2 films were successfully prepared on graphene electrodes for solar-cell applications. CuInS2 films were deposited on high-quality graphene via reactive sputtering using a system with facing targets. This high-quality graphene was grown via chemical vapour deposition. The obtained CuInS2 films on graphene were highly (112)-oriented, and their crystallite size was enhanced compared with that of films grown on conventional Mo electrodes. The graphene/CuInS2 interfaces clearly exhibited ohmic characteristics comparable to those of Mo/CuInS2. Our experimental results demonstrate the high potential of graphene electrodes for use in CuInS2 thin-film and multi-junction solar cells.