Interfacial engineering of 0D/2D CoMn2O4 nanoparticles/CdS nanosheets p-n heterostructures for boosted photocatalytic H2 production and U(VI) reduction

Developing effective heterojunction photocatalysts that efficiently separate charge carriers and improve light-harvesting capabilities is crucial in addressing energy and environmental issues. Herein, a unique nanocomposite photocatalyst is constructed by attaching CoMn2O4 nanoparticles onto 2D CdS nanosheets for H2 production and U(VI) reduction. The optimized 2% CoMn2O4/CdS nanocomposite showcases the highest photocatalytic H2 production efficiency, 5.8 times higher than CdS nanosheets. Additionally, the U(VI) reduction rate constant of 2% CoMn2O4/CdS is 0.0192 min−1, approximately 1.9 folds over the pristine CdS (0.0101 min−1). The exceptional photocatalytic performance toward photocatalytic H2 evolution and U(VI) reduction reactions directly result from the electronic integration between CoMn2O4/CdS p-n heterojunction, facilitated by the efficient photoexcited charge separation. Feasible photocatalytic mechanisms are proposed through experimental analyses and theoretical calculations. This study provides a straightforward method for designing effective CdS-based heterostructured photocatalysts, contributing to the advancement of solar-to-H2 conversion and environmental abetment.