Highly selective hydrogen peroxide electrosynthesis on copper phthalocyanine: interface engineering with an azo-polymer

The two-electron oxygen reduction reaction provides a new green route for the sustainable production of H2O2, which is cost-effective, less energy-intensive and environmentally friendly compared to the industrial anthraquinone method. However, the activity and stability of the catalyst is still in urgent need of improvement. Herein, the electrode-electrolyte (solid-liquid) interface was adjusted by surface modification of a catalyst, and the modified CuPc-NO2 catalyst with azo molecules exhibited an improved selectivity of H2O2 by 30-50%. Furthermore, the electrode surface was further modified by doping F into the azo molecule to enhance the HO2-desorption property of the catalyst. The proposed CuPc-TAP-F catalyst showed a 98% selectivity of H2O2 with a stability of 40 h and a wide potential window of 0.8 VRHE (>= 90% selectivity), reaching a relatively high level in the field of H2O2 electrosynthesis from the point of view of both efficiency and stability. The electrode-electrolyte interface was adjusted by azo molecule modification to improve the desorption of HO2-. The H2O2 selectivity and stability of CuPc-TAP-F in a wide potential window is a higher level in the field of H2O2 electrosynthesis.