Rational design of carbon-based metal-free catalysts for electrochemical carbon dioxide reduction: A review

Electrochemical CO₂ reduction to chemicals or fuels presents one of the most promising strategies for managing the global carbon balance, which yet poses a significant challenge due to lack of efficient and durable electrocatalyst as well as the understanding of the CO₂ reduction reaction (CO₂RR) mechanism. Benefiting from the large surface area, high electrical conductivity, and tunable structure, carbon-based metal-free materials (CMs) have been extensively studied as cost-effective electrocatalysts for CO₂RR. The development of CMs with low cost, high activity and durability for CO₂RR has been considered as one of the most active and competitive directions in electrochemistry and material science. In this review article, some up-to-date strategies in improving the CO₂RR performance on CMs are summarized. Specifically, the approaches to optimize the adsorption of CO₂RR intermediates, such as tuning the physical and electronic structure are introduced, which can enhance the electrocatalytic activity of CMs effectively. Finally, some design strategies are proposed to prepare CMs with high activity and selectivity for CO₂RR. © 2019 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences.