Development of Ag Assisted Three-Dimensional Porous Cu Nanostructures for Synergistic Reduction of CO2 to Ethanol
In this work, a Cu-based electrocatalyst was rationally designed, where the deposition time and current of synthesis parameters for a three-dimensional porous Cu catalyst were optimized to study their influence on electrochemical performance in CO2 reduction. Morphological and topological investigation of surface nanostructures through scanning electron microscopy (SEM) and vertical scanning interferometry (VSI) suggested a dependence of electrochemically active surface area on deposition time, where 200 mA deposition current for 400 seconds demonstrated the highest electrochemical activity. Further, to improve upon the intrinsic selectivity of Cu, an Ag thin film was incorporated within the porous Cu catalyst for synergistic catalysis of CO2 at Ag sites followed by further reduction of the intermediates towards hydrocarbons at Cu active sites. Analysis of generated gas and liquid phase products revealed a total faradaic efficiency (FE) of 94.7% towards carbonaceous products, yielding a FE of 35.2% towards Ethanol, and 59.5% towards CO.