Electrochemical Mass Spectrometry: Evolution of the Cell Setup for On‐Line Investigation of Products and Screening of Electrocatalysts for Carbon Dioxide Reduction

One of the most important current topics in the renewable and sustainable energy scenario is the CO2 electro‐reduction reaction (CO2RR), which is an alternative and important route for its conversion into various high value‐added chemicals, therefore making up a CO2 recycling process. Despite its importance and the works already developed in this field, many challenges still need to be overcome for CO2RR to reach high values of efficiency and selectivity. This is even more challenging considering that this reaction occurs with the transfer of several electrons, making the investigation and elucidation of the reaction mechanism a real need. Thus, several characterization techniques have been employed, and specially, the on‐line Electrochemical Mass Spectrometry (EC‐MS) technique emerges as a powerful tool, thus making possible to improve the understanding of reaction pathways, through the identification of products and intermediaries, and allowing the screening of electrocatalyst potentials for CO2RR. Herein, we present the evolution of adaptations of general electrochemical cell designs for the study of the CO2RR. Evolution of EC‐MS: The technique of electrochemical mass spectrometry (EC‐MS) has great potential in investigating and elucidating reaction mechanisms of redox processes and in the screening of new electrocatalysts. With an immense application in the most varied studies in the electrochemistry field, this technique is a powerful tool in studying the electrochemical conversion of CO2 into fuels and valuable products.