Synergistic carbon and hydrogen reactions in the electrochemical reduction of CO2 to liquid fuels

Abstract

The electrochemical reduction reaction for the conversion of CO₂ to liquid fuels in aqueous conditions (e-CO₂RR-lf) is one of the promising methods for converting the greenhouse gas into easy-storage fuels. Unfortunately, electrocatalysts for e-CO₂RR-lf cannot satisfy the industrial requirements because they are sluggish in kinetics and poor in selectivity. To ensure the activity and selectivity of e-CO₂RR-lf on electrocatalysts, the carbon reaction (CO₂ to carbon intermediates and then to organic liquid fuels) and hydrogen reaction (hydrogenation of the carbon intermediates) in e-CO₂RR-lf should be fast and generate specific intermediates for basic reactions with high selectivity. Therefore, the rational design of the composition and structure of electrocatalysts is critical to improving the catalytic performance of these two reactions in e-CO₂RR-lf. In this review, we comprehensively discuss the strategies for designing electrocatalysts to enhance the hydrogen and carbon reactions. Suggestions to control the composition and structure of electrocatalysts that can accelerate the reaction rate and the selectivity of hydrogen and carbon reactions, and improve the rate and selectivity of e-CO₂RR-lf are given at the end. We expect that the concepts of promoting e-CO₂RR-lf by enhancing the hydrogen and carbon reactions can guide the design and fabrication of electrocatalysts with high performance in the near future.