Photovoltaic-driven stable electrosynthesis of H2O2 in simulated seawater and its disinfection application

Abstract

Electrosynthesis of H₂O₂ through O₂ reduction in seawater provides bright sight on the H₂O₂ industry, which is a prospective alternative to the intensively constructed anthraquinone process. In this work, a photovoltaic-driven flow cell system is built for the electrosynthesis of H₂O₂ in simulated seawater using N-doped carbon catalysts. The N-doped carbon catalysts with multiple N-doped carbon defects can achieve a record-high H₂O₂ production rate of 34.7 mol g_catalyst⁻¹ h⁻¹ under an industrially relevant current density of 500 mA cm⁻² and a long-term stability over 200 h in simulated seawater (0.5 M NaCl). When driven by the photovoltaic system, a H₂O₂ solution of ∼1.0 wt% in 0.5 M NaCl is also obtained at about 700 mA cm⁻². The obtained solution is applied for disinfection of mouse wounds, with a removal rate of 100% for Escherichia coli and negligible toxicity to living organisms. It provides bright prospects for large-scale on-site H₂O₂ production and on-demand disinfection.