Amorphization and Pd Loading Synergistically Enable Bulk-to-Surface Charge Carrier Separation for Efficient Photocatalytic H2O2 Production

Abstract A major challenge in artificial photosynthesis for H2O2 production arises from rapid charge recombination and non-selective side reactions. Herein, we design a Pd-decorated amorphous ZnCdS (Pd/AZCS) photocatalyst. Amorphization promotes bulk charge separation, while Pd loading enhances interfacial transfer, synergistically improving H2O2 selectivity and yield. Theoretical calculations reveal that amorphization and Pd loading synergistically enhance the dipole moment and modulate the electronic structure, resulting in significantly improved O2 adsorption capability. Spectroscopic analyses further confirm enhanced charge carrier separation and the formation of key intermediates in the oxygen reduction reaction (ORR). Consequently, the optimized Pd/AZCS achieves an impressive H2O2 evolution rate of 120.6 μmol g–1 min–1 in pure water without any sacrificial agents, representing a nearly 13-fold enhancement over pristine ZnCdS (ZCS). This work provides a pivotal strategy for efficient and durable photocatalytic H2O2 synthesis, highlighting its substantial promise for industrial-scale renewable energy applications.