(678g) Correlating Experimentally Determined CO Binding Energy with Electrochemical CO Reduction Performance on Cu Surface

Electrochemical reduction of CO₍₂₎ to high value products offers an appealing route to store sustainable energy and make use of the chief greenhouse gas CO₂. With the modest affinity of CO, Cu-based materials remain to be the most important electrocatalysts for producing valuable multi-carbon products. Many catalyst design works reported the tuned CO binding energy on Cu-based materials, while such claims were mainly based on computational results. Therefore, it is crucial to develop a reliable experimental technique for determining the CO binding energy of catalysts at CO₍₂₎RR conditions.

In this talk, we present several newly designed surface enhanced infrared absorption spectroscopy (SEIRAS) cells to characterize the CO binding energy on Cu-based electrodes. We have, for the first time, characterized the standard adsorption enthalpy of CO adsorption at electrochemical conditions by developing a SEIRAS cell with controllable temperatures and revealed that the modest adsorption enthalpy of CO on dendritic Cu (Den Cu) could attribute to the competitive adsorption of CO and water. High-pressure SEIRAS measurement was also conducted to estimate the absolute coverage on Den Cu, leading to the evaluation of standard Gibbs free energy and entropy. To understand the impact of CO binding energy on CORR performance, the standard adsorption enthalpy of CO on oxide-derived Cu was also estimated, suggesting that our temperature-controllable SEIRAS could distinguish the strong CO binding sites on different Cu catalysts.