Cu2S decorated MoSe2 nanosheets as counter electrode for quantum dot sensitized solar cells

Abstract

The power conversion efficiency of quantum dot sensitized solar cells (QDSCs) is limited by poor redox activity of the sulfide/polysulfide electrolyte toward the counter electrodes. Here, we demonstrate the use of MoSe2-Cu2S nanoheterostructures as an efficient counter electrode in QDSCs. The QDSC based on MoSe2-Cu2S counter electrode displays an efficiency of 3.6%, which is ∼17% higher as compared to Cu2S counter electrode. The improvement is resulting from the efficient shuttling of charge carriers across the two dimensional network of MoSe2 nanosheets owing to the decrease of charge transfer resistance.