Electrochemical Manufacturing of Hydrogen Peroxide with High Concentration and Durability

Electrochemical manufacturing of hydrogen peroxide (H₂O₂) via oxygen reduction reaction (ORR) has been widely recognized as an alternative to the conventional anthraquinone process, but the output H₂O₂ concentration that it can reach and the long-term electrolysis stability are still far from industrial requirements. Here, we report the promising potential of the porous solid electrolyte (PSE) reactor for producing high-concentration and high-purity H₂O₂ in high stability. By identifying the issue of high H₂O₂ concentration at the cathode/membrane interface that could lead to membrane degradation and low ORR Faradaic efficiencies (FEs), we adopted a water recirculation flow operation instead of continuous flow to effectively carry out the generated H₂O₂ product from the PSE layer without interfacial accumulation. This recirculation strategy boosted the H₂O₂ FE from 23% to 50% to produce a 30 wt % H₂O₂ stream and successfully extended the lifetime of the PSE reactor to ∼1000 h while continuously outputting 20 wt % H₂O₂ under 100 mA cm^–2 operation current.