Graphene oxide modified hole transport layer for CH3NH3PbI3 planar heterojunction solar cells

This work reports on graphene oxide (GO) and poly(3,4-ethylenedioxy thiophene)-poly(styrenesulfonate) (PEDOT:PSS) hybrid bilayer as hole extracting layer for CH3NH3PbI3-based inverted planar heterojunction perovskite solar cells. Remarkably, the incorporation of GO could suppress leakage current and reduce recombination via efficient hole transporting and electron blocking, resulting in 30% improvement of power conversion efficiency.