Recent Progress in Atomically Dispersed Non‐noble Metal Catalysts for Electrochemical Two‐electron Oxygen Reduction Reaction

Abstract

Abstract Electrochemical two‐electron oxygen reduction reaction (2e− ORR) has emerged as an efficient route to generate hydrogen peroxide (H2O2) under ambient conditions, being a promising alternative to the traditional energy‐intensive anthraquinone process and direct synthesis route using H2 and O2. However, this 2e− ORR process still requires highly efficient electrocatalysts to adsorb and activate O2 with two‐electron reaction pathway. Among all investigated 2e− ORR electrocatalysts to date, non‐noble metal single atom catalysts (SACs) with tunable electronic structure and different coordination structures manifest great potential in controlling ORR pathway to obtain high‐efficiency H2O2 production. In this review, recent advances and achievements in tuning non‐noble metal SACs for selective 2e− ORR to H2O2 are systematically summarized. Especially, the strategies to effectively regulate the catalytic active sites of non‐noble metal SACs for optimizing the binding strength of key oxygenated intermediates during 2e− ORR are emphatically exhibited and reviewed. Finally, we also point out the challenges and outlooks about the development of non‐noble metal SACs in H2O2 electrosynthesis and the diverse utilization of in‐situ formed H2O2 for biomass upgrading. This review would be helpful to guide the design and development of efficient SACs for electrochemical 2e− ORR to H2O2 under ambient conditions.

Keywords

• electrocatalysis
• non-noble metal single-atom sites
• two-electron oxygen reduction reaction
• *OOH binding strength
• H2O2 electrosynthesis