Accelerating *OH Desorption via Electron‐Delocalized Cu _Td ²⁺ ─O─Co _Oh ³⁺ for Water Purification

Abstract The electrochemical oxidation (EO) process has the unique advantage of in situ generation of reactive oxygen species for organic synthesis and wastewater purification. However, the strong binding of H ₂ O and anode inhibits the desorption of reactive oxygen species, exacerbating their peroxidation into oxygen and thus weakening EO performance. In this work, an electron delocalization strategy is proposed by introducing Cu ²⁺ into the tetrahedral sites (A _Td ²⁺ ) of Co ₃ O ₄ (Cu _x Co _3‐x O ₄ ) to trigger the super‐exchange effect of Cu _Td ²⁺ ─O─Co _Oh ³⁺ , constructing the electron‐rich Co _Oh ³⁺ sites and accelerating the desorption *OH for the promotion of EO performance. Experimental results confirm the electron‐delocalized Cu _Td ²⁺ ─O─Co _Oh ³⁺ disrupts the kinetic equilibrium of oxygen evolution reaction and balances the energy barriers of H ₂ O adsorption, H ₂ O dehydrogenation, and *OH desorption over Co _Oh ³⁺ sites, thus realizing the •OH‐mediated EO process. The required free energy for •OH generation decreases from 1.14 to 0.70 eV. The Cu _x Co _3‐x O ₄ anode has extraordinary EO activity for the elimination of multiple aromatic contaminants and demonstrates feasibility in practical landfill leachate treatment. This study offers an in‐depth understanding of active species formation in EO systems and guides the design and synthesis of superior and stable electrodes for efficient conversion of organic matter.