Boosting photocatalytic hydrogen peroxide production by regulating electronic configuration of single Sb atoms via carbon vacancies in carbon nitrides.

Single-atom catalysts supported on semiconductors can serve as active sites for efficient oxygen reduction to hydrogen peroxide (HO). However, researchers have long been puzzled by the lack of guidance on optimizing the performance of single-atom photocatalysts. In this study, we propose a versatile strategy that utilizes carbon vacancies to regulate the electronic configuration of antimony (Sb) atoms on carbon nitrides (CN). This strategy has been found to significantly enhance the photocatalytic production of HO. The HO evolution rate of Sb single-atom on carbon vacancy-rich CN (designated as Sb/Cv-CN) is 5.369 mmol gh, which is 10.9 times higher than CN alone. By combining experimental characterizations and density functional theory simulations, we reveal the strong electronic interaction between Sb atoms and carbon vacancy-rich CN. This interaction is capable for maintaining the electron-rich state of Sb atoms, facilitating efficient electron transfer to pauling-type absorbed oxygen, and ultimately enhancing the formation of *OOH intermediates. This innovative defect-engineering approach can manipulate the electronic configuration of single-atom catalysts, providing a new avenue to boost the photocatalytic oxygen reduction reaction towards HO production.