Tandem strategy for electrochemical CO2 reduction reaction

Abstract

The electrochemical CO 2 reduction reaction (CRR) is a promising technique with which to achieve carbon balance, and strategies for improving CRR performance are of great significance. Inspired by nature, catalysts can be designed with dissimilar active sites to trigger different fundamental reactions, and tandem reactions facilitating CO 2 fixation or transformations of primary products to deeply reduced chemicals are also involved in photosynthesis. For the electrochemical CRR, developing efficient tandem strategies is also an emerging approach to improve the catalytic selectivity and output values. Herein, we first introduce the history and principles of tandem strategies used in the electrochemical CRR field. Then, recent advances in metal-based tandem catalysts, tandem cathodic reactions designed for tandem catalysis to improve the electrocatalytic CRR, and tandem devices to enhance CRR performance are systematically summarized. Finally, the challenges and perspectives of tandem strategies as well as the electrochemical CRR are also discussed. Electrocatalytic CO 2 reduction into value-added chemicals has drawn increasing attention due to the great potential for addressing the issues of greenhouse effect, energy crisis, and industrial transformation. The practical application of electrochemical CO 2 reduction is hindered by limited current density and selectivity for producing value-added chemicals. A recently developed tandem strategy has enlightened the way to achieve better electrochemical performances of CRR. Based on the principles of tandem strategy, this review systematically summarized tandem catalysts, tandem cathodic reactions, and tandem devices in detail. Some representative strategies have demonstrated promising results to enhance the electrocatalytic activity and selectivity for electrochemical CRR. Further overcoming the carbonate and energy use efficiency issues via developing efficient electrocatalysts, value-added tandem reactions, and electrolyzing systems may facilitate the electrochemical CRR technology for industrial applications. Tandem strategies involving tandem catalysts, tandem reactions, and tandem devices are emerging and efficient approaches to improve the selectivity of electrochemical CO 2 reduction into value-added products.