Chapter 16: Electrochemical CO₂ Reduction

The electrochemical reduction of CO₂ has strongly emerged as a promising approach to recycle the gas and generate e-fuels and e-chemicals. It amounts to storing electricity under the form of dense energy and stable chemicals. Toward this goal, metal molecular complexes as well as solid metal based materials may be used as catalysts for generating the target products. Designing efficient catalysts (being both stable, selective and fast) requires understanding the operating mechanisms by which CO₂ is reductively transformed. Such a task necessitates combining electrochemical and spectroscopic operando methods, and theoretical calculations. This chapter presents an overview of the recent efforts along these lines. Results and lessons obtained from studies devoted to C1 (e.g. CO, CH₃OH, CH₄) and C2/C2+ (e.g. ethanol, ethylene, acetic acid, etc.) products are presented, and we further identify the challenges for controlling these processes. All these efforts are mandatory for the emergence of electrochemical technologies able to recycle CO₂ on a large scale.