Glassification Induced Crystalline/Amorphous Interfaces for Bifunctional Electrocatalysis Pairing 5‐Hydroxymethylfurfural Oxidation and Hydrogen Evolution

Abstract As one of the very limited examples, herein, a bifunctional electrocatalyst featured with crystalline/amorphous interfaces between crystalline CuO and ZIF‐Co glass (ZIF‐Co(g)) is developed for efficient electrocatalysis pairing 5‐hydroxymethylfurfural (HMF) oxidation and hydrogen evolution reaction (HER), receiving a high current density of 102.1 mA cm −2 at 1.45 V versus reversible hydrogen electrode (RHE) for HMFOR, with 100% HMF conversion, 99.5% 2,5‐furandicarboxylic acid (FDCA) yield, and 99.1% FDCA faradaic efficiency (FE), and also providing a small overpotential of 98 mV to reach a current density of 10 mA cm −2 for HER. Excitingly, the membrane electrode assembly (MEA) electrolyzer integrated with CuO@ZIF‐Co(g) as both anode and cathode affords 95.4% FDCA yield and 99.7% H 2 FE at 200 mA cm −2 . Experimental results and theoretical calculations demonstrate that the glassification induced crystalline/amorphous interfaces will create an interfacial electric field directing from ZIF‐Co(g) to CuO. This electric field will deepen electrochemical reconstruction to generate CoOOH active sites with enhanced intrinsic activity for HMFOR. Meanwhile, the interfacial charge redistribution will modulate the d‐band center at Co sites and enhance the *H adsorption, thereby accelerating HER kinetics. This work develops an innovative interface engineering approach for designing efficient bifunctional electrocatalysts toward biomass upgrading and green hydrogen production.