Recent advances in the electrochemical CO reduction reaction towards highly selective formation of Cx products (X = 1–3)

Abstract

The electrochemical conversion of carbon monoxide (CO) to high-value chemicals has been extensively explored as a promising strategy for carbon utilization. Robust electrocatalysts with high activity and selectivity are critically important for the industrial application of CO reduction reaction (CORR). Here, we review a broad spectrum of progress toward high-rate CO conversion to C 1 –C 3 products, including mechanistic insights, catalyst development, and device designs that can improve performance even further. Detailed discussions provide a rational understanding of how the key parameters, including catalyst surface facets, nanostructures, electrolyte effects, and electrochemical conditions, enhance the catalytic performance. Finally, we discuss the current challenges and possible future directions for advanced catalysts, analysis, and systems toward efficient CO reduction. Although electrochemical CO 2 reduction reaction (CO 2 RR) has been considered a promising carbon-neutrality system, its low level of selectivity for the production of specific chemicals limits further developments, except for the conversion of CO 2 to CO (>99% selectivity). Recently, the electrochemical CO reduction reaction (CORR) has been receiving a great deal of attention owing to its better selectivity for conversion to specific chemicals than that of CO 2 RR. Accordingly, the development of a two-step tandem system consisting of CO 2 to CO conversion and CO to specific chemical conversion is considered to have the potential to achieve high selectivity of the entire CO 2 conversion system. To enhance the understanding of current CORR technology and aid in the development of related fields, this review provides mechanistic insights and key parameters, including catalyst surface faceting, nanostructuring, electrolyte effects, electrochemical conditions, and device design, used to promote the CORR activity and selectivity. This review provides a broad spectrum of progress toward CO reduction reaction to value-added C x products (X = 1–3), including mechanistic insights, catalyst development, and device designs. The current challenges and possible future directions for advanced catalysts, analysis, and systems toward efficient CO reduction are also discussed.