Engineering Ru‐Complementary Catalytic Centers on Co ₂ P/CoP Heterojunction for Industrial Alkaline Water Electrolysis

Abstract Advancing industrial‐scale water electrolysis critically hinges on developing ultra‐active and ultra‐durable catalysts. Herein, a novel Ru‐doped Co ₂ P/CoP heterostructure electrocatalyst (Ru‐Co ₂ P/CoP/CF) is fabricated via an in situ self‐derivation strategy. By regulating the spatial distribution of Ru in the Co ₂ P/CoP heterojunction, the coexisting system integrating Ru atomic clusters (AC) and Ru single atoms (SA) is engineered. Further poisoning experiments and DFT calculations reveal that the dual Ru species exhibit complementary catalytic functionalities for the hydrogen/oxygen evolution reactions (HER/OER). The electron‐rich Ru AC improves the H ₂ O‐adsorption and *OH desorption, boosting the Volmer step of the HER process. While the electron‐deficient Ru SA accelerates OER kinetics by promoting O* desorption and weakening *OOH binding. Moreover, the Co ₂ P/CoP heterojunction establishes an electron equilibration channel, which provides adaptive electron supply and antioxidative microenvironment to Ru, mitigating Ru solvation by stabilizing its electronic states. Benefiting from the Ru‐complementary catalytic centers and heterojunction‐driven charge equilibration, Ru‐Co ₂ P/CoP/CF demonstrates top‐level properties and stability in 1.0 M KOH, requiring ultralow overpotentials of 98 mV (HER) and 360 mV (OER) at 1 A cm ⁻² , along with stability of 4000 h. This work overcomes the selectivity dilemma of single‐type Ru sites for HER/OER, and offers a scalable in‐situ self‐derivation strategy for designing high‐efficiency TMPs electrocatalysts.