Phosphorous and selenium tuning Co-based non-precious catalysts for electrosynthesis of H 2 O 2 in acidic media

Electrosynthesis of hydrogen peroxide (H 2 O 2 ) is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable features. The crucial point remains developing highly active, selective and cost-effective electrocatalysts. The electrosynthesis of H 2 O 2 in acidic media is more practical owing to its stability and no need for further purification. We herein report a phosphorus and selenium tuning Co-based non-precious catalyst (CoPSe) toward two-electron oxygen reduction reaction (2e - ORR) to produce H 2 O 2 in acidic media. The starting point of using both P and Se is finding a balance between strong ORR activity of CoSe and weak activity of CoP. The results demonstrated that the CoPSe catalyst exhibited the optimized 2e - ORR activity compared with CoP and CoSe. It disclosed an onset potential of 0.68 V and the H 2 O 2 selectivity 76%-85% in a wide potential range (0-0.5 V). Notably, the CoPSe catalyst overcomes a significant challenge of a narrow-range selectivity for transitionmetal based 2e - ORR catalysts. Finally, combining with electro-Fenton reaction, an on-site system was constructed for efficient degradation of organic pollutants. This work provides a promising non-precious Co-based electrocatalyst for the electrosynthesis of H 2 O 2 in acidic media. (c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.