Advances and challenges in the electrochemical reduction of carbon dioxide.

The electrocatalytic carbon dioxide reduction reaction (ECO 2 RR) is a promising way to realize the transformation of waste into valuable material, which can not only meet the environmental goal of reducing carbon emissions, but also obtain clean energy and valuable industrial products simultaneously. Herein, we first introduce the complex CO 2 RR mechanisms based on the number of carbons in the product. Since the coupling of C-C bonds is unanimously recognized as the key mechanism step in the ECO 2 RR for the generation of high-value products, the structural-activity relationship of electrocatalysts is systematically reviewed. Next, we comprehensively classify the latest developments, both experimental and theoretical, in different categories of cutting-edge electrocatalysts and provide theoretical insights on various aspects. Finally, challenges are discussed from the perspectives of both materials and devices to inspire researchers to promote the industrial application of the ECO 2 RR at the earliest.