Tailoring electrocatalysts for on-site H 2 O 2 production via two electron oxygen reduction

Hydrogen peroxide (H2O2) is a versatile green oxidant widely used in various fields. However, conventional synthesis methods such as the anthraquinone process suffer from high energy consumption, pollution, and safety risks. The electrocatalytic two-electron oxygen reduction reaction (2e⁻ ORR) offers a sustainable alternative by using O2 and H2O as feedstocks under ambient conditions, enabling on-site production with minimal environmental impact. This makes it a key research direction in the field. The main challenge for 2e⁻ ORR toward H2O2 lies in regulating the adsorption energy of the *OOH intermediate while preserving the O-O bond. Based on the reaction mechanism, this Review systematically summarizes recent progress in precious metal catalysts, carbon-based catalysts, metal oxide catalysts, and single-atom catalysts (SACs), along with on-site reactors and applications. It highlights current bottlenecks, including the trade-off among activity, selectivity, and stability, difficulties in large-scale synthesis, and limited real-world adaptability. Future efforts should focus on atomic-level catalyst design, green large-scale synthesis, system integration, and exploration of emerging catalytic systems. This Review aims to provide insights to accelerate the industrialization of electrocatalytic H2O2 production.