Influence of Atomic-Level Morphology on Catalysis: The Case of Sphere and Rod-Like Gold Nanoclusters for CO₂ Electroreduction

Gold-based materials hold promise in electrocatalytic reduction of CO₂ to fuels. However, the polydispersity of conventional gold nanostructures limits mechanistic studies. Here, we report two types of atomically precise Au₂₅ nanoclusters (1 nm) with distinct morphology (i.e., nanosphere and nanorod) for CO₂ reduction catalysis. The Au₂₅ nanosphere exhibits higher Faradaic efficiency for CO with higher formation rates compared to the Au₂₅ nanorod. First-principles calculations reveal that the negative charge and the energetically favorable removal of one ligand to generate an active site on the nanosphere can better stabilize the important *COOH intermediate in CO₂ electroreduction