Synergistic effect of triphase interface and fluid control for efficient photosynthesis of residue-free H2O2

Solar-to-chemical energy conversion is a challenging subject for renewable energy storage. Solar-driven hydrogen peroxide (H2O2) synthesis is a sustainable and potentially economic technology. Despite great efforts in catalyst engineering, photocatalytic H2O2 production is usually limited by the sluggish oxygen diffusion and H2O2 decomposition side reactions, leading to poor apparent photocatalytic H2O2 production efficiency. Herein, we developed a fluid triphase system that enables both the efficient interfacial oxygen mass transfer and the inhibited H2O2 decomposition side reactions. Such a synergistic effect endowed a residue-free H2O2 production rate of 6.03 μmol h−1 from pure water and oxygen without using any sacrificial agent or additive, with over 120 h continuous irradiation stability. We further designed a photosynthesis-concentration tandem system to produce high concentration H2O2 (10 mM), which demonstrated an effective water disinfection capability as a representative application.