Electrocatalytic Coupling Conversion of Methane by Dual‐Site Control in Nickel Oxyhydroxide

ABSTRACT Methane (CH ₄ ), as both a carbon resource and greenhouse gas, requires an effective and ecologically friendly catalysis to accomplish the conversion into valued‐added chemicals or fuels, wherein the establishment of a proper multi‐site active structure to boost the C─H dissociation and C─C coupling demands further exploration. Herein, we disclose a facile and general approach by controlling the electronic property of Ni to preserve a moderate orbital hybridization (d‐p) with O, and thereby induce a synergistic Ni─O dual‐site for the expected electrocatalysis of CH ₄ toward C ₂ product. Specifically, along the d band shifting downwards via the Ni valence increase, the optimal NiOOH not only affords sufficient capability for the CH ₄ oxygenation relative to the Ni(OH) ₂ , but also minimizes the probability of O detachment compared with the NiO ₂ . The resultant NiOOH catalyst exhibits the highest Faradaic efficiency of 53.5% with a production rate of 401.6 µmol g _cat. ⁻¹ h ⁻¹ or 1.61 µmol h ^‒1 cm ^‒2 for acetic acid, and a long‐term stability for over 50 h without detectable structural deterioration. This study develops an efficient electrocatalytic CH ₄ process, and could arouse extensive attention to the new materials and routes meeting the economicity and sustainability.