Enhancing charge transport performance of perovskite solar cells by using reduced graphene oxide-cysteine/nanogold hybrid material in the active layer

Abstract

To enhance carrier transport, the internal charge transfer resistance of organic–inorganic metal halide perovskite solar cells (PVSCs) was reduced through the formation of well-distributed nanogold-graphene–based conductive networks in the matrix of the active layer. In this study, a reduced graphene oxide-cysteine/nanogold (rGO-CysAu) hybrid material was prepared and incorporated into PVSCs. Nanogold particles were modified with the amino acid cysteine and successfully deposited onto the surface of graphene oxide. To prepare inverted PVSCs, rGO-CysAu with a highly uniform distribution of gold nanoparticles on the rGO surface was added to the perovskite precursor solution. The incorporation of rGO-CysAu into PVSCs resulted in a 12% increase in power conversion efficiency, improving perovskite charge transport efficiency and crystallization. Consequently, PVSCs with rGO-CysAu had improved average efficiency of 20.59% compared to 18.32% for control cells.