Nature Communications, Published online: 31 August 2026; doi:10.1038/s41467-026-75533-4 PEC H2O2 production usually suffers from low selectivity and poor stability. This study shows a Zn-TiO2/BVO/WO3∥Ru:CuO/Nb-CBO bipolar system that enables efficient and stable H2O2 synthesis under sunlight, achieving a combined Faradaic efficiency of 163.37%.