Carrier management through electrode and electron-selective layer engineering for 10.70% efficiency antimony selenosulfide solar cells

Abstract

Antimony selenosulfide (Sb₂(S,Se)₃) solar cells suffer from charge carrier loss, which has limited the power conversion efficiency to around 10%. Here we develop a charge carrier management strategy using a textured fluorine-doped tin oxide substrate as the front contact to enhance light scattering and maximize charge generation. To overcome voids and shunt paths introduced by the textured surface, we insert a SnO₂ layer by atomic layer deposition at the textured fluorine-doped tin oxide/CdS interface. This results in a conformal deposition of CdS and an optimal bandgap profile in the Sb₂(S,Se)₃ absorber, which improves charge transport and lowers charge recombination at the interface and in the bulk, respectively. We achieve a certified efficiency of 10.70% sodium selenosulfate-based Sb₂(S,Se)₃ solar cells with excellent stability. We prove the generality of the method demonstrating selenourea-based Sb₂(S,Se)₃ and upscaling the solar cells to 1 cm². The results represent a step forward in the development of antimony-based solar cells.