Carbon dioxide electroreduction (CO₂ER) exploited in conjugation with renewable energy sources can open the path to a carbon-neutral energy cycle, concurrently offering the possibility to synthesize low-carbon fuels. In the last decades, a huge amount of work has been carried out by the scientific community in order to obtain high-performing and low-cost catalysts, and to design reactors able to maximize the efficiency of CO₂ER. Electrochemical impedance spectroscopy (EIS) proved to be a useful tool in studying this electrochemical reaction, and has been widely employed to characterize novel materials and reactor architectures. The aim of this Review is to provide an insight on the application of EIS for the study of CO₂ER. A brief introduction on the technique and on the reaction will be given, followed by a review of the most important applications in this field. Finally, a brief discussion of future research directions will be presented.

与可再生能源结合使用的二氧化碳电解还原（CO ₂ ER）可以为实现碳中性能源循环开辟道路，同时也提供了合成低碳燃料的可能性。在过去的几十年中，科学界已经进行了大量工作，以便获得高性能和低成本的催化剂，并设计出能够使CO ₂ ER效率最大化的反应器。电化学阻抗谱（EIS）被证明是研究这种电化学反应的有用工具，已被广泛用于表征新型材料和反应器结构。这篇综述的目的是对EIS在CO ₂研究中的应用提供一个见解。ER。将简要介绍该技术和反应，然后回顾该领域最重要的应用。最后，将对未来的研究方向进行简短的讨论。