Electrosynthesis of H2O2 aqueous solution beyond 30 wt% using sunlight, water and air

Abstract

The industrial anthraquinone process produces H₂O₂ solution with concentrations greater than 27.5 wt%; however, concerns regarding process safety, pollutant discharge and product purification remain. Here, we report an electrosynthesis system that directly produces H₂O₂ solution exceeding 30 wt% under ambient conditions using only sunlight, water and air. Benefiting from a carbon-based catalyst that achieves 17.86 mol g⁻¹ h⁻¹ H₂O₂ yield and up to 99.4% two-electron oxygen reduction reaction selectivity, the integrated electrosynthesis system can produce 30 wt% H₂O₂ continuously for more than 500 hours without noticeable degradation. Moreover, electronic-grade products were obtained without downstream purification. This work establishes an electrochemical route to produce high concentration and high-purity H₂O₂ that directly meets the needs of the chemical and semiconductor industries, advancing the electrification of chemical engineering processes in a sustainable way.