Synthesis & Characterization of Ni‐Ga and Fe‐Ga Nanoparticles for Electrochemical Carbon Dioxide Reduction

Abstract

A major challenge encountered in electrochemical reduction of carbon dioxide on single transition metal surfaces is that most of them are incapable of producing higher-order carbon-containing products. Mechanistic insight describing free energy barriers of the conversion processes between surface-bound carbon intermediates suggests that combinations of alloyed metals could overcome this lack of desired activity. Organic- and aqueous-phase syntheses are evaluated for Ni-Ga and Fe-Ga alloy nanoparticle production, and the nanoparticles are electrochemically tested for their ability to reduce carbon dioxide. Only Ni-Ga is found to be electrocatalytic, generating formate at a Faradaic efficiency of 36% at –1.38 V vs. Ag/AgCl. The successful synthesis of Ni-Ga nanoparticles using the organic-phase synthesis procedure, as well as their electrochemical characterization, is reported for the first time. The production of formate implies selective stabilization via oxophilic binding sites for trigonal oxygen-containing surface carbon intermediates.