Atomic Cu Sites Engineering Enables Efficient CO(2) Electroreduction to Methane with High CH(4)/C(2)H(4) Ratio

Electrochemical reduction of CO(2) into high-value hydrocarbons and alcohols by using Cu-based catalysts is a promising and attractive technology for CO(2) capture and utilization, resulting from their high catalytic activity and selectivity. The mobility and accessibility of active sites in Cu-based catalysts significantly hinder the development of efficient Cu-based catalysts for CO(2) electrochemical reduction reaction (CO(2)RR). Herein, a facile and effective strategy is developed to engineer accessible and structural stable Cu sites by incorporating single atomic Cu into the nitrogen cavities of the host graphitic carbon nitride (g-C(3)N(4)) as the active sites for CO(2)-to-CH(4) conversion in CO(2)RR. By regulating the coordination and density of Cu sites in g-C(3)N(4), an optimal catalyst corresponding to a one Cu atom in one nitrogen cavity reaches the highest CH(4) Faraday efficiency of 49.04% and produces the products with a high CH(4)/C(2)H(4) ratio over 9. This work provides the first experimental study on g-C(3)N(4)-supported single Cu atom catalyst for efficient CH(4) production from CO(2)RR and suggests a principle in designing highly stable and selective high-efficiency Cu-based catalysts for CO(2)RR by engineering Cu active sites in 2D materials with porous crystal structures. [Image: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s40820-023-01188-1) contains supplementary material, which is available to authorized users.