Interfacial Electronic Interactions in Ni ₁ Cu Single-Atom Alloys Enhance Carbon Dioxide Electrocatalytic Conversion

Copper-based single-atom alloys (SAAs) exhibit unique capabilities to catalyze the conversion of CO₂ into valuable fuels and chemicals, yet their high polarization often induces surface reconstruction, limiting their stability under practical conditions. Here, a novel SAA catalyst, Ni₁Cu/NC, featuring atomically dispersed Ni on ∼3 nm Cu nanoparticles anchored on a nitrogen-doped carbon substrate was developed. Density functional theory suggests that energy-aligned and symmetry-compatible mixing of Ni 3d with Cu 4s/4p states enhances s/p-d hybridization on the Cu sites and induces partial delocalization of Cu d-band electrons, modulating the adsorption of key intermediates. As a result, Ni₁Cu/NC achieved near-unity CO Faradaic efficiency (FE_CO) and remarkable durability of 160 h. Furthermore, coupling the catalyst with an anode for the 5-hydroxymethylfurfural oxidation reaction in a solar-driven system renders a high 2,5-furandicarboxylic acid yield of 97.3%. This work provides a comprehensive framework for the rational design of supported SSA catalysts.