Addressing Mechanistic Studies on Electrochemical CO2 Reduction Based on ATR-Seiras

Strategies to reduce net CO2 emissions have had a significant progress in recent years. In particular, electrochemical reduction of CO2 presents a sustainable path to produce valuable fuels and industrially relevant chemicals while contributing to the process of global decarbonization. High activity and selectivity toward carbon products, and avoidance of CO2 crossover in alkaline electrolytes are crucial to make this process viable. To this end, recent studies have shown that selective electrocatalysis of this reaction on acidic conditions is possible only in the presence of metal cations, however It´s still uncertain the underlying mechanism by which the cation enhancement occurs or the impact that the identity of the cations have. This study aims to advance our understanding of this mechanism by exploring the molecular interactions on the catalyst-electrolyte interface with the use of in-situ/operando techniques, for this we conduct surface-sensitive ATR-SEIRAS experiments supported by grazing incidence XRD characterizations and electrochemical performance testing, which are also critical to shed light into key intermediates during CO2 reduction reaction. The key to achieve strong SEIRAS activity relies on appropriate reflection, conduction and catalytic activity of the metal film, giving that it serves as both the source of surface enhancement and the working electrode, so consequently, we also develop a detailed methodology for tailoring the catalyst surface, particularly building on Au deposition procedures in ITO-coated silicon chips in the way of improving the IR, taking advantage on surface plasmon resonance These efforts in catalyst design will translate into a hybrid ITO-Gold film electrode, that should reveal cation-dependent fundamental electrochemical phenomena that promote CO2 reduction in acid electrolytes, given that gold is active for CO2 reduction and ATR-SEIRAS.