Durable Photosynthesis of Hydrogen Peroxide Using a Uranyl Coordination Polymer: Exciton Dissociation and Hydrogen Abstraction

The photosynthesis of hydrogen peroxide (H₂O₂), involving water oxidation and oxygen reduction, is crucial for optimizing light utilization. Here, a previously synthesized one-dimensional chain-like semiconductive uranyl coordination polymer (NDC-UCP) was used for the efficient overall photosynthetic reaction of H₂O₂ and its photocatalytic mechanism was systematically investigated. The excellent stability of NDC-UCP enables continuous H₂O₂ production for up to 96 h. Its unique hydrogen extraction capability enhances the photocatalytic performance, achieving a H₂O₂ production rate of 283.80 μmol g^-1 h^-1. Two mechanisms for H₂O₂ generation were revealed: efficient electron-hole separation in NDC-UCP facilitates a two-step one-electron oxygen reduction and direct water oxidation, while hydrogen abstraction of UO₂²⁺ generates hydroxyl (·OH) and hydroperoxyl radicals (HO₂^·), enhancing H₂O₂ photosynthesis. This study highlights the potential of uranyl coordination polymers in H₂O₂ production and their synergistic exciton dissociation and hydrogen abstraction functionalities in photocatalytic redox reactions.