Atomically Correlated Phosphorus-Sulfur Sites in Carbon Nitride for Efficient Hydrogen Peroxide Production

Photocatalytic oxygen reduction offers a sustainable route to hydrogen peroxide (H₂O₂) production; however, rapid charge-carrier recombination and sluggish oxygen-reduction reaction (ORR) kinetics remain the primary bottlenecks. Herein, an atomically correlated phosphorus-sulfur co-doped graphitic carbon nitride (g-C₃N₄), referred to as P-S:gCN, is demonstrated to enable efficient H₂O₂ photogeneration in O₂-saturated water without sacrificial agents. Introducing atomically correlated P-S sites within the heptazine framework creates an asymmetric charge distribution that suppresses trap-mediated recombination and promotes efficient charge separation. These coupled heteroatom sites also enhance oxygen adsorption and activation on the catalytic surface, directing the reaction through the selective 2e^- ORR pathway to increase H₂O₂ generation. Under visible-light irradiation, P-S:gCN achieves an apparent quantum yield of 6.80% at 420 nm and a solar-to-chemical conversion efficiency of 0.49% in pure water. Combined experimental and theoretical evidence reveals that atomically correlated P-S sites regulate charge transport, suppress recombination, and promote selective 2e^- ORR more effectively than isolated dopants. This atomically correlated dual-site engineering opens avenues for tuning charge transport, electronic structure, and the stability of reaction intermediates in metal-free photocatalytic systems.