A Review of Interface Engineering in Antimony Chalcogenide Thin Film Solar Cells

Antimony chalcogenides (Sb 2 X 3 , where X = S, Se, or S x Se 1−x ) are promising materials for thin‐film solar cells due to their tunable bandgaps (1.1–1.8 eV), high absorption coefficients (>10 5 cm −1 ), nontoxicity, and earth‐abundant composition. Recent advancements have achieved power conversion efficiencies (PCEs) exceeding 10%, with a record of 10.81% for Sb 2 (S, Se) 3 cells. However, interface‐related issues, such as recombination losses and open‐circuit voltage ( V OC ) deficits, limit performance. Interface engineering strategies have significantly improved device efficiency and stability, including buffer layer optimization, defect passivation, surface treatments, post‐processing, and doping. This review summarizes the latest developments in these areas, discusses ongoing challenges, and proposes future research directions to enhance the performance of antimony chalcogenide solar cells.