Hydrophobic carbon quantum dots with Lewis-Basic nitrogen sites for electrocatalyst CO 2 reduction to CH 4

Metal-free carbon-based catalysts offered a promising alternative for efficient electrochemical carbon dioxide reduction (ECO 2 RR), presenting potential advantages over transition metal-based counterparts. However, challenges such as low Faraday efficiencies and limited current densities persist. Herein, we synthesized CQDs with high Lewis basic sites to enhance CO 2 adsorption and activation, resulting in an optimized CQD-2 catalyst that achieved a Faradaic efficiency of 52.00 % and a current density of 178 mA cm −2 for CH 4 production. In situ characterizations unveiled that CO 2 was activated into *COOH intermediates, which further converted to *CO species. Concurrently, activated H 2 O molecule ionized into protons, facilitating reaction kinetics. This research provides valuable insights into designing carbon-based catalysts with high Lewis base content, offering significant prospects for advancing high-performance ECO 2 RR technologies.