Tuning Binding Strength of Multiple Intermediates towards Efficient pH‐universal Electrocatalytic Hydrogen Evolution by Mo ₈ O ₂₆ ‐NbN _x O _y Heterocatalysts

Abstract

Developing efficient and robust hydrogen evolution reaction (HER) catalysts for scalable and sustainable hydrogen production through electrochemical water splitting is strategic and challenging. Herein, heterogeneous Mo₈ O₂₆ -NbN_x O_y supported on N-doped graphene (defined as Mo₈ O₂₆ -NbN_x O_y /NG) is synthesized by controllable hydrothermal reaction and nitridation process. The O-exposed Mo₈ O₂₆ clusters covalently confined on NbN_x O_y nanodomains provide a distinctive interface configuration and appropriate electronic structure, where fully exposed multiple active sites give excellent HER performance beyond commercial Pt/C catalyst in pH-universal electrolytes. Theoretical studies reveal that the Mo₈ O₂₆ -NbN_x O_y interface with electronic reconstruction affords near-optimal hydrogen adsorption energy and enhanced initial H₂ O adsorption. Furthermore, the terminal O atoms in Mo₈ O₂₆ clusters cooperate with Nb atoms to promote the initial H₂ O adsorption, and subsequently reduce the H₂ O dissociation energy, accelerating the entire HER kinetics.