Interfacial Engineering by Indium-Doped CdS for High Efficiency Solution Processed Sb₂(S_1–xSe_x)₃ Solar Cells

Sb₂(S_{1- x}Se _x)₃ alloy material is a kind of encouraging material for realistically apposite solar cell because it benefits from high absorption coefficient, suitable bandgap, superior stability, and plentiful elemental storage. Interfacial engineering is vital for effective charge carrier transport in solar cells, which could upgrade the photoelectric conversion efficiency (PCE). Herein, as an interlayer, indium-doped CdS thin film fabricated by chemical bath deposition is found to remarkably enhance the photovoltaic performance of Sb₂(S_{1- x}Se _x)₃ solar cells. Mechanistic investigations show that the interlayer can both optically and electrically optimize the device quality. With that a PCE of 6.63% is obtained, which is the highest efficiency among the planar heterojunction solar cells and slightly higher than the reported record efficiency of mesoscopic Sb₂(S_{1- x}Se _x)₃-sensitized solar cells. This research provides an efficient interfacial engineering for high performance Sb₂(S_{1- x}Se _x)₃ solar cells.