Graphene/silicon photoelectrode with high and stable photoelectrochemical response in aqueous solution

The graphene (Gr)/Si electrodes were fabricated by electrophoresis method and then following an annealing process. The p-Si surface was found to be covered completely with successive and transparent Gr sheets, and thus the impairment of aqueous solution on the photoelectrochemical capability of silicon could be avoided. This annealing process was a key process for improving the adhesion of Gr/Si interface. After annealing at 400 °C, the Gr/Si electrodes displayed high photoresponse ability and high stability in aqueous solution. The carriers transfer between Gr and Si is discussed on the basis of the semiconductor energy band theory. The results demonstrated that the Gr/Si electrodes would be a promising candidate as solar energy materials using in aqueous solution.