Efficient and Stable Antimony Selenoiodide Solar Cells

Although antimony selenoiodide (SbSeI) exhibits a suitable bandgap as well as interesting physicochemical properties, it has not been applied to solar cells. Here the fabrication of SbSeI solar cells is reported for the first time using multiple spin‐coating cycles of SbI(3) solutions on Sb(2)Se(3) thin layer, which is formed by thermal decomposition after depositing a single‐source precursor solution. The performance exhibits a short‐circuit current density of 14.8 mA cm(−2), an open‐circuit voltage of 473.0 mV, and a fill factor of 58.7%, yielding a power conversion efficiency (PCE) of 4.1% under standard air mass 1.5 global (AM 1.5 G, 100 mW cm(−2)). The cells retain ≈90.0% of the initial PCE even after illuminating under AM 1.5G (100 mW cm(−2)) for 2321 min. Here, a new approach is provided for combining selenide and iodide as anions, to fabricate highly efficient, highly stable, green, and low‐cost solar cells.