Advances in copper-based electrocatalysts for electrochemical reduction of CO2 to ethanol: Operando, theoretical, and empirical perspectives

One of the most effective methods for achieving carbon neutrality is the Electrochemical Carbon Dioxide Reduction Reaction (CO₂RR). The conversion of CO₂ to ethanol using the electrochemical method is quite challenging primarily due to the numerous electron and proton transfers (EPT) required for the CC bond formation process. Currently, copper-based electrocatalysts are widely preferred for CO₂RR ought to their ability to address the primary challenge of EPT in electrochemical cells. In this review, we examine the recent advancements in the field of Cu-based electrocatalysts for electrochemical CO₂RR to produce ethanol. Herein, we discuss how the morphologies and defects of the Cu catalytic surface impact the activity and selectivity of ethanol. Subsequently, we explore different spectroscopic methods, computations utilizing Density Functional Theory (DFT), and the implementation of Machine Learning (ML) algorithms. This aids to a better understanding of the insights of the mechanism of the Cu-based electrocatalysts for the ethanol production. Finally, we delve into the empirical studies, particularly, the categories of electrocatalysts that exhibit measurable Faradic Efficiency (F.E.) of ethanol. Overall, this review highlights the critical importance of integrating the theoretical, and experimental approaches for effective and selective ethanol conversion.