Electrochemical, Scanning Electrochemical Microscopic, and <i>In</i> <i>Situ</i> Electrochemical Fourier Transform Infrared Studies of CO<sub>2</sub> Reduction at Porous Copper Surfaces
Allison Salverda, Sharon Abner, Emmanuel Mena‐Morcillo, Adam Zimmer, Abdallah Elsayed, Aicheng Chen
Abstract
There is significant interest in the design of high-performance electrocatalysts for efficient electrochemical reduction of CO 2 to address the pressing environmental issue and climate change. Herein, a novel copper–aluminum nanostructured catalyst is fabricated via an alloying/dealloying technique. The effect of the initial alloy’s elemental composition and subsequent dealloying, via HCl acid treatments, on the stability and activity of the catalyst for electrochemical CO 2 reduction is studied. The optimized porous catalyst shows high catalytic activity for the electrochemical CO 2 reduction reaction (CO 2 RR) with current efficiencies achieving greater than 81%. Gas and liquid product analysis confirms the formation of CO, H 2, and HCOO – . Scanning electrochemical microscopy was employed to monitor the activity of the catalyst and the CO 2 RR products. In situ electrochemical FTIR spectroscopic studies revealed the first CO 2 RR intermediate was carbon-bound to the acid-treated 50:50 Cu/Al (at. %) alloy surface in a monodentate orientation. The synthetic approach reported in the present study leads to a new promising electrocatalyst with superior catalytic activity and high efficiencies for the effective electrochemical reduction of CO 2 to valuable products.