Efficiency enhancement of dye-sensitized solar cells (DSSCs) using ligand exchanged CuInS2 NCs as counter electrode materials

Abstract

Exploring inorganic ligand capped nanocrystals (NCs) as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs) with high conversion efficiency. Here, we reported the preparation of inorganic ligand capped CuInS₂ NCs through a ligand exchange strategy. After ligand exchange, the organic ligand capped on the surface of CuInS₂ NCs were exchanged to inorganic ligand S²⁻ without changing the shape, size distribution and crystal structure of CuInS₂ NCs. When used as CE materials for dye-sensitized solar cells, the inorganic ligand capped CuInS₂ NCs films showed higher electrocatalytic activity and electrical conductivity, thus can significantly improve the efficiency of DSSCs. It should be noted that the conversion efficiency of the DSSC increased by 17 times after the organic ligand capped CuInS₂ NCs were exchanged with the inorganic ligand. The study in this work may pave a new pathway to explore highly electrical conductivity materials for DSSCs.