Efficient and selective photocatalytic oxidation of benzylic alcohols with built-in electric field CsPbBr3/SiO2 nanocomposites through Fe3+ gradient doping

Lead halide perovskite nanocrystals (PNCs) have emerged as promising materials for photocatalysis due to their exceptional optoelectronic properties, yet achieving efficient charge separation and selective oxidation reactions remains a significant challenge. In this study, we report the synthesis of Fe 3+ -doped CsPbBr 3 /SiO 2 nanocomposites (Fe-PNCs/SNPs) with gradient energy levels, designed to enhance photocatalytic performance. Our results demonstrate that Fe 3+ doping introduces mid-gap states, promotes photoinduced charge separation, and generates reactive oxygen species (ROS) such as O 2 − and OH radicals under sunlight-simulating light irradiation from a 300 W Xe arc lamp. The Fe 20 -PNCs/SNPs catalyst achieved over 99 % conversion of benzyl alcohol to benzaldehyde with high selectivity and stability in the ethanol under ambient conditions. Additionally, the catalyst exhibited excellent recyclability and broad substrate tolerance. These findings highlight the innovative design of gradient energy levels in perovskite nanocomposites, offering a new strategy for enhancing photocatalytic efficiency in selective organic transformations.