On-Demand Synthesis of H O by Water Oxidation for Sustainable Resource Production and Organic Pollutant Degradation.

H O is a versatile and environmentally friendly chemical involved in water treatment, such as advanced oxidation processes. Anthraquinone oxidation is widely used for large-scale production of H O , which requires significant energy input and periodic replacement of the carrier molecule. H O production should be customized considering the specific usage scenario. Electrochemical synthesis of H O can be adopted as alternatives to traditional method, which avoids concentration, transportation, and storage processes. Herein, we identified Bi WO :Mo as a low-cost and high-selectivity choice from a series of Bi-based oxides for H O generation via two-electron water oxidation reaction. It can continuously provide H O for in situ degradation of persistent pollutants in aqueous solution. Clean energy from H can also be produced at the cathode. This kind of water splitting producing sustainable resources of H O and H is an advance in environmental treatment and energy science.