Applications of in-situ spectroscopic techniques towards CO₂ electroreduction

In-situ experimental techniques have been widely applied to uncover the dynamic evolutions of both the structure of catalysts and the interfacial property of catalysis, thus serving as the most important means to gain molecular-level insights into the reaction mechanisms. In this mini review, we summarized recent progress in the applications of the interface-sensitive in-situ Raman and in-situ infrared (IR) spectroscopy towards CO₂ electroreduction. Specifically, we concentrated on two aspects to clarify the role of both in-situ Raman and in-situ IR in revealing reaction mechanisms of CO₂ electroreduction. The first one was the in-situ spectroscopy for detecting the active structures. The other one was the in-situ spectroscopy for capturing the reaction intermediates. As powerful guidance for the rational design of catalysts, the reaction mechanism was discussed in the specific examples. Finally, we try to predict the trends for the future development of in-situ spectroscopic techniques towards heterogeneous catalysis.