Efficient and Selective Electrocatalytic Hydrogenation of 5‐Hydroxymethylfurfural Over CuAg Heterostructures

ABSTRACT The valorization of biomass‐derived platform molecules driven by renewable electricity is widely regarded as a green and sustainable approach, in which the rational design of electrocatalysts is crucial for achieving efficient and selective conversion. Herein, a series of CuAg heterostructured electrocatalysts was constructed in situ on copper foam (CF) substrates via a two‐step electrodeposition method for the electrocatalytic hydrogenation of 5‐hydroxymethylfurfural (HMF) to 2,5‐bis(hydroxymethyl)furan (BHMF). Experimental results demonstrate that initial Cu deposition plays an important role in increasing the electrochemically active surface area (ECSA) and enhancing interfacial synergy. Subsequent introduction of Ag significantly lowers the onset overpotentials for both the hydrogen evolution reaction (HER) and the electrocatalytic hydrogenation (ECH) of HMF, thereby accelerating the overall reaction kinetics and effectively suppressing the dimerization side reaction. The optimized CuAg/CF‐2 catalyst achieves 92.1% HMF conversion and 88.9% BHMF selectivity within only 1 h of electrolysis, with a BHMF productivity of 0.164 mmol cm −2 h −1 . Density functional theory calculations reveal that Ag incorporation modulates the electronic structure of Cu sites and constructs a CuAg heterointerface with characteristic geometric features, which facilitates the generation of adsorbed hydrogen (H*), enhances the adsorption and activation of HMF, while simultaneously promoting BHMF desorption and suppressing competitive HER.