Hollow ZnCdS/CuInS ₂ S‑Scheme Heterojunction for Superior Photothermal‐Assisted Photocatalytic Coupled H ₂ O ₂ and Benzaldehyde Production

ABSTRACT Photocatalytic H 2 O 2 production coupled with selective oxidation of benzyl alcohol represents a highly attractive yet challenging “one‐stone‐two‐birds” strategy for sustainable chemical synthesis. The major obstacles lie in the difficulty of synchronizing spatial charge separation, preserving high redox potentials, and precisely steering the reaction pathways. Herein, a novel hollow ZnCdS/CuInS 2 S‐scheme heterojunction is constructed through solid‐solution band engineering. This multifunctional design integrates three synergistic effects to break the above limitations: (i) rapid charge separation driven by S‐scheme heterojunction while retaining strong redox capability; (ii) broad‐band light harvesting and photothermal effect facilitated by hollow nanobox architecture; (iii) ideal reaction kinetics and thermodynamics optimized by photothermal temperature rise. The developed catalyst achieves remarkable co‐production rates under full‐spectrum irradiation: 3052.5 µmol g −1 h −1 for H 2 O 2 and 5211.6 µmol g −1 h −1 for benzaldehyde, with nearly 100% selectivity for benzaldehyde. It is unraveled that the photothermal‐induced moderate local heating triggers a controllable homolysis of H 2 O 2 , generating a favorable concentration of hydroxyl radicals. This process enables precise activation of the C─H bonds in benzyl alcohol while suppressing unwanted over‐oxidation pathways. This work establishes a paradigm for advanced photocatalytic coupling systems, where charge‐separation engineering and photothermal‐microenvironment regulation act in concert to promote efficient and selective solar‐to‐chemical conversions.