Electronic Structure Modulation of Oxygen-Enriched Defective CdS for Efficient Photocatalytic H₂O₂ Production

Artificial photosynthesis for hydrogen peroxide (H₂O₂) presents a sustainable and environmentally friendly approach to generate clean fuel and chemicals. However, the catalytic activity is hindered by challenges such as severe charge recombination, insufficient active sites, and poor selectivity. Here, a robust strategy is proposed to regulate the electronic structure of catalyst by the collaborative effect of defect engineering and dopant. The well designed oxygen-doped CdS nanorods with S^2- defects and Cd²⁺ 4d10 electron configuration (CdS-O,S_v) is successfully synthesized, and the Cd²⁺ active sites around S defects or oxygen atoms exhibit rapid charge separation, suppressed carrier recombination, and enhanced charge utilization. Consequently, a remarkable H₂O₂ production rate of 1.62 mmol g^-1 h^-1 under air conditions is acquired, with an apparent quantum yield (AQY) of 9.96% at a single wavelength of 450 nm. This work provides valuable insights into the synergistic effect between defect and doping on catalytic activity.