Structural Features of Electrodeposited Copper Electrodes for CO<sub>2</sub> Conversion

Abstract

Direct electrochemical reduction of CO2 is a process that could contribute to the reduction of the emission of greenhouse gases by using CO2 as a raw material for fuel production. This paper focuses on voltammetric studies of functionalized electrodes for the electrochemical conversion of CO2 and reports on its use as a tool for electrode screening and optimization. Nickel substrates modified with copper and ruthenium/copper electrodeposits were studied. Voltammetric experiments indicate that CO2 electroreduction follows a nickel type mechanism in which this electrochemical reaction occurs simultaneously and in competition with hydrogen evolution. A significant inhibition of hydrogen evolution reaction is observed in nickel modified electrodes. Inhibition characteristics and the onset of carbon dioxide conversion are dependent of the type of electrode functionalization. Voltammetry is thus a powerful tool to evaluate electrode modifications and for tuning electrodes for an optimized electrocatalytic performance.