Modified carbon paper anode coupled with a natural air-diffusion cathode for synchronous electrosynthesis of hydrogen peroxide

Electrochemical synthesis of hydrogen peroxide （H₂O₂） is a highly promising route for H₂O₂ production, which can proceed via two pathways: the two-electron water oxidation reaction at the anode and the two-electron oxygen reduction reaction at the cathode. However, current electrochemical H₂O₂ production is still dominated by single-electrode reaction modes, resulting in relatively low faradaic efficiency. To address this issue, we designed and fabricated a poly（vinylidene fluoride） (PVDF)-coated carbon fiber paper （CFP） anode and a natural air-diffusion cathode that operates without forced aeration, and further constructed an anode-cathode coupled electrochemical system for H₂O₂ synthesis. The results show that: （1） PVDF coating enhances the hydrophobicity and aerophilicity of CFP, thereby improving the anode performance for electrochemical H₂O₂ synthesis; （2） the optimized natural air-diffusion cathode employs carbon cloth as the gas diffusion layer, PVDF as the binder, and oxidized carbon black with a loading amount of 7.5 mg cm⁻² as the catalyst; and （3） in a proton exchange membrane separated electrolytic cell, the coupled anode-cathode system achieved a total current efficiency of 151.5% and an H₂O₂ production rate of 36.9 μmol min⁻¹ at 3 V vs. RHE, with anodic and cathodic faradaic efficiencies of 52.9% and 98.6%, respectively. In addition, the system operated stably for more than 12 h, during which the accumulated amount of H₂O₂ reached 4.2 mmol. These results demonstrate that the synergistic coupling of a hydrophobic and aerophilic CFP anode with a naturally air-diffusion cathode can significantly improve the overall faradaic efficiency for H₂O₂ production, providing a new strategy for its green and efficient electrochemical synthesis.