A highly selective copper-indium bimetallic electrocatalyst for the electrochemical reduction of aqueous CO2 to CO

Angew Chem Int Ed Engl. 2015 Feb 9;54(7):2146-50. doi: 10.1002/anie.201410233. Epub 2014 Dec 23.

Abstract

The challenge in the electrochemical reduction of aqueous carbon dioxide is in designing a highly selective, energy-efficient, and non-precious-metal electrocatalyst that minimizes the competitive reduction of proton to form hydrogen during aqueous CO2 conversion. A non-noble metal electrocatalyst based on a copper-indium (Cu-In) alloy that selectively converts CO2 to CO with a low overpotential is reported. The electrochemical deposition of In on rough Cu surfaces led to Cu-In alloy surfaces. DFT calculations showed that the In preferentially located on the edge sites rather than on the corner or flat sites and that the d-electron nature of Cu remained almost intact, but adsorption properties of neighboring Cu was perturbed by the presence of In. This preparation of non-noble metal alloy electrodes for the reduction of CO2 provides guidelines for further improving electrocatalysis.

Keywords: Cu-In alloy; carbon dioxide fixation; electrocatalysis; electrochemistry; reaction mechanisms.