关键词: 两电子氧还原反应, 过氧化氢, 电化学合成, 碳基催化剂, 选择性

Abstract:

The production of hydrogen peroxide (H₂O₂) via electrochemical two-electron (2e^-) oxygen reduction reaction (ORR) is a green, safe and efficient technical route, showing broad development prospects as an alternative to the industrial anthraquinone process. However, this route at present is limited by the sluggish ORR kinetics and the competitive four-electron (4e^-) reaction, and thus it is critically desired to develop efficient catalysts with high ORR activity and selectivity. Currently, carbon-based materials are the most widely studied catalysts for electrosynthesis of H₂O₂via 2e^- ORR and great progress has been made due to their abundance in earth, low cost and tunable catalytic properties. This review summarizes the recent advances in carbon-based electrocatalysts for 2e^- ORR to H₂O₂. Fundamental principles of the ORR and general methods of electrocatalyst evaluation are first introduced and the basic design guidelines for constructing highly-efficient electrocatalyst is also pointed out. Next, with a focus on the non-metal carbon-based materials and transition-metal carbon-based materials, the active site optimization strategies of catalysts including heteroatom doping, defect engineering, pore engineering and single-atom site local environment regulation are in depth discussed. Finally, the challenges and future development trend in the field of H₂O₂^{electrosynthesis by 2e- ORR are proposed in terms of H₂O₂ production medium, catalyst structure-performance relationship and steady production under industrial current densities.}

Key words: two-electron oxygen reduction reaction, hydrogen peroxide, electrochemical synthesis, carbon-based catalysts, selectivity