Morphology Regulation and Photocatalytic CO₂ Reduction of Lead-Free Perovskite Cs₃Sb₂I₉ Microcrystals

A huge prospect of lead halide perovskites can be found in the fields of optoelectronics and photocatalysis. However, the main obstacle to their photocatalytic application is their toxicity. To shake off these issues, lead-free Cs₃Sb₂I₉ perovskite microcrystals with different morphologies were synthesized via a simple hot-injection approach. Furthermore, the as-prepared Cs₃Sb₂I₉ microcrystals were utilized for photocatalytic CO₂ reduction, achieving a total electron yield of 14.2 μmol g^–1 under visible-light irradiation (λ ≥ 420 nm, 300 W Xe lamp) within 3 h. Our work here provides an idea for the application of lead-free perovskites for photocatalytic CO₂ reduction.