Electrocatalytic H2O2 production paired with value-added chemicals synthesis, contaminant remediation, and electricity generation

Hydrogen peroxide (H2O2) electrosynthesis emerged as a noteworthy alternative to the anthraquinone process, primarily due to its capability to harness renewable electrical energy. However, the conventional H2O2 electrosynthetic reaction (HPR) usually incorporates the oxygen evolution reaction (OER) functioning as a sacrificial half-reaction. The sluggish kinetics and high overpotential associated with OER, coupled with the low-value O2 by-product, result in considerable energy consumption and diminished efficiency. The design of paired electrolysis reactions facilitates the production of H2O2 at the cathode while generating high value-added products or degrading pollutants at the anode, thereby optimizing the utilization of charges at both electrodes. This approach can theoretically achieve an overall Faradaic efficiency of up to 200%, significantly reducing the energy consumption and total costs associated with paired electrolysis. Professor Dionysiou has conducted extensive research into H2O2 synthesis for advanced oxidation pollution control, and his recent work on paired electrolysis has provided valuable insights into this field. Despite the importance of this topic, related research remains fragmented and lacks concentrated discussion. Consequently, this work offers a comprehensive review and analysis of the paired electrolysis systems of H2O2 electrosynthesis. The main content is organized into three sections: synergistic electrosynthesis of H2O2 and high value-added chemicals, H2O2 electrosynthesis paired with pollutant degradation, and co-generation of H2O2 and electricity. This review offers new insights into the current challenges and opportunities within this rapidly evolving field. Additionally, it presents a forward-looking perspective on the future development of H2O2 electrosynthesis systems that utilize paired electrolysis, along with their practical applications.