In situ Raman spectroscopy studies for electrochemical CO2 reduction over Cu catalysts

An accurate understanding of reaction mechanisms is crucial for the rational design of highly efficient catalytic materials for electrochemical CO2 reduction reaction (CO2RR). In situ characterization methods are powerful to reveal structure-performance correlations of working catalysts under reaction conditions. Electrochemical in situ Raman spectroscopy is able to probe catalyst structures as well as reaction intermediates on/near catalyst surfaces in an electrochemical environment. In this short review, we briefly introduce the principle of electrochemical in situ Raman spectroscopy and highlight recent advances of its applications in tracking structure evolution of catalyst surfaces and identifying reaction intermediates during CO2RR over selected Cu catalysts. The research challenges and opportunities of investigating CO2RR mechanisms using electrochemical in situ Raman spectroscopy are also proposed.