Interface Chemical Bond Enhanced Ions Intercalated Carbon Nitride/CdSe‐Diethylenetriamine S‐Scheme Heterojunction for Photocatalytic H2O2 Synthesis in Pure Water

Abstract Photosynthesis of hydrogen peroxide (H 2 O 2 ) is regarded as an economically efficient and environmentally friendly synthesis method. However, the scalability of photocatalytic H 2 O 2 production (PHP) is hindered by the sluggish reaction kinetics and rapid recombination of photogenerated charge carriers. In this study, an organic amine‐constrained ions intercalated carbon nitride/CdSe‐diethylenetriamine (K + /I − ‐CN/CdSe‐D) S‐scheme heterojunction is synthesized using an organic–inorganic hybrid approach and employed for PHP for the first time. The optimization of the heterojunction interface by I − and K + ions contributed to enhanced light absorption capabilities and reduced interlayer charge transfer distance. Concurrently, the synergy of C─Se bonds at interface effectively modulated the electron transfer pathways. The coordination environment and charge transfer mechanism are thoroughly investigated by extended X‐ray absorption fine structure and in situ irradiated X‐ray photoelectron spectroscopy. The H 2 O 2 production rate of 40%K + /I − ‐CN/CdSe‐D reached 2240.23 µmol h −1 g −1 in pure water. This study highlights the significance of dual tuning of interface chemical bonds and ionic intercalation as an effective strategy for enhancing the photocatalytic H 2 O 2 , paving the way for further advancements in PHP technology.