Hybrid Nanoparticles: Ni and Au Decorated with [FeFe]-Hydrogenase Mimics

Complexes [(μ-S₂C₂H₄NHR)Fe₂(CO)₆] (R = p-C₆H₄-OCO(CH₂)₉Br (3a); R = p-C₆H₄-OCO(CH₂)₈CH₃ (3b)) were used as stabilizing agents in the synthesis of Ni@3 and Au@3 nanoparticles (NPs), which are the first reported stable metallic NPs decorated with [(μ-S₂C₂H₄NHR)Fe₂(CO)₆] moieties. Electrochemical analysis reveals that incorporating the hydrogenase mimic into the NPs lowers the overpotential and enhances proton reduction electrocatalytic activity in organic media. The NPs act similarly to the [Fe₄S₄] cluster in natural enzymes, functioning as an electron reservoir/relay.