CO2 Electrochemical Reduction As Probed through Infrared Spectroscopy

CO2 electrochemical reduction shows great promise in storing renewable energy and alleviating global warming. Its large-scale applications in the industry, however, are still in infancy mainly due to the unsatisfactory performance of electrocatalysts. Rational design of advanced electrocatalysts would be the ultimate solution, which has yet to be achieved currently because of the lack of understandings of reaction mechanisms. In the past few years, in situ attenuated total reflection infrared (ATR-IR) spectroscopy has been successfully adopted to study the electrochemical interface of the CO2 reduction reaction (CO2RR) and significantly advanced our understandings of this reaction. In this Perspective, these advances as well as the challenges and opportunities faced in further studying CO2RR by this technique are discussed.