Facet Effects on OD-Cu Catalysts for Electrochemical Hydrogenation of Furfural

A key biomass-derived platform molecule, furfural (FF), offers immense potential for synthesizing valuable chemicals like furfuryl alcohol (FAL) through catalytic hydrogenation. Copper-based catalysts stand out for this conversion owing to their adjustable active sites, economic viability, and decent stability. Nevertheless, conventional Cu electrodes exhibit limited performance, and the atomic-scale catalytic mechanisms remain unclear. In this study, we developed a series of oxide-derived copper (OD-Cu) catalysts with precisely controlled Cu(100) to Cu(111) facet ratios for the electrochemical hydrogenation of furfural. Remarkably, the cube-shaped OD-Cu catalyst, dominated by Cu(100) facets, delivered an exceptional FAL selectivity of 97.7%, far exceeding the 61.1% selectivity achieved by its octahedron-shaped counterpart with predominant Cu(111) facets. Density functional theory (DFT) calculations provided atomic-level insights, revealing that the Cu(100) surface induces greater elongation of the aldehyde C═O bond in adsorbed FF compared to Cu(111), indicating superior activation of this critical functional group. Additionally, the calculations demonstrated stronger furfural adsorption on Cu(100) than on Cu(111). These combined effects synergistically enhance catalytic performance.