High‐rate electrochemical H₂O₂ production over multimetallic atom catalysts under acidic–neutral conditions

Abstract Hydrogen peroxide (H₂O₂) production by the electrochemical 2‐electron oxygen reduction reaction (2e⁻ ORR) is a promising alternative to the energy‐intensive anthraquinone process, and single‐atom electrocatalysts show the unique capability of high selectivity toward 2e⁻ ORR against the 4e⁻ one. The extremely low surface density of the single‐atom sites and the inflexibility in manipulating their geometric/electronic configurations, however, compromise the H₂O₂ yield and impede further performance enhancement. Herein, we construct a family of multiatom catalysts (MACs), on which two or three single atoms are closely coordinated to form high‐density active sites that are versatile in their atomic configurations for optimal adsorption of essential *OOH species. Among them, the Co_x–Ni MAC presents excellent electrocatalytic performance for 2e⁻ ORR, in terms of its exceptionally high H₂O₂ yield in acidic electrolytes (28.96 mol L⁻¹ g_cat.⁻¹ h⁻¹) and high selectivity under acidic to neutral conditions in a wide potential region (>80%, 0–0.7 V). Operando X‐ray absorption and density functional theory analyses jointly unveil its unique trimetallic Co₂NiN₈ configuration, which efficiently induces an appropriate Ni–d orbital filling and modulates the *OOH adsorption, together boosting the electrocatalytic 2e⁻ ORR capability. This work thus provides a new MAC strategy for tuning the geometric/electronic structure of active sites for 2e⁻ ORR and other potential electrochemical processes.