Cd0.5Zn0.5S/Bi2MoO6S-Scheme Heterojunction Photocatalyst for the Degradation of Dyes and the Oxidation of Amines

Abstract

Designing nanoscale photocatalysts is essential for advancing solar-driven organic synthesis and environmental remediation. Among various strategies, constructing S-scheme heterojunctions has shown great promise in overcoming charge recombination and maintaining strong redox potentials. In this study, we report a Cd0.5Zn0.5S/Bi2MoO6S-scheme heterojunction photocatalyst with dual functionality for Rhodamine B degradation and selective benzylamine oxidation under visible-light irradiation. The optimized 5.0 wt % Cd0.5Zn0.5S/Bi2MoO6nanostructure exhibited superior photocatalytic activity, achieving nearly complete Rhodamine B degradation and enhanced benzylamine photooxidation. Spectroscopic and electrochemical characterizations confirmed the formation of an internal electric field that facilitates efficient charge separation. Furthermore, the addition of Cd0.5Zn0.5S not only enables heterojunction formation but also improves product selectivity toward N-benzylidene-1-benzylamine. Density functional theory calculations revealed that Cd0.5Zn0.5S suppresses the generation of superoxide radicals, thereby limiting the formation of undesired byproducts dependent on these species. This work highlights the role of nanoscale interface engineering in tuning charge dynamics and reactive oxygen species pathways, offering a viable strategy for developing selective and efficient photocatalytic nanomaterials. © 2025 The Authors. Published by American Chemical Society