Solution-Processed Compact Sb₂S₃ Thin Films by a Facile One-Step Deposition Method for Efficient Solar Cells

Antimony sulfide (Sb₂S₃) is a promising photon-harvesting material for solar cells. Herein, a facile one-step deposition method is reported for controllably preparing Sb₂S₃ nanoparticle films with a preferential [221]-orientation to a certain extent from a novel precursor solution, formed by dissolving antimony acetate and thiourea in acidified N,N-dimethylformamide. With titania (TiO₂) nanoparticle films as substrates for in situ-growing Sb₂S₃ films, the high-quality Sb₂S₃/TiO₂ planar heterojunction films are obtained for efficient solar cells. The effects of the concentration and [S]/[Sb] molar ratio in the precursor solution on the Sb₂S₃ film formation and the device performance are investigated. A considerable power conversion efficiency of 5.74% is achieved under AM 1.5G illumination (100 mW cm⁻²), which is the highest efficiency for the solar cells based on solution-processed Sb₂S₃ nanoparticle films by one-step deposition method without further modification. A promising solution-processing method is provided to prepare high-quality Sb₂S₃ films for efficient solar cells and other optoelectronics.