Lewis Acid Site-Promoted Single-Atomic Cu Catalyzes Electrochemical CO₂ Methanation

Developing an efficient catalyst for the electrocatalytic CO 2 reduction reaction (CO 2 RR) is highly desired because of environmental and energy issues. Herein, we report a single-atomic-site Cu catalyst supported by a Lewis acid for electrocatalytic CO 2 reduction to CH 4 . Theoretical calculations suggested that Lewis acid sites in metal oxides (e.g., Al 2 O 3, Cr 2 O 3 ) can regulate the electronic structure of Cu atoms by optimizing intermediate absorption to promote CO 2 methanation. Based on these theoretical results, ultrathin porous Al 2 O 3 with enriched Lewis acid sites was explored as an anchor for Cu single atoms; this modification achieved a faradaic efficiency (FE) of 62% at −1.2 V (vs RHE) with a corresponding current density of 153.0 mA cm –2 for CH 4 formation. This work demonstrates an effective strategy for tailoring the electronic structure of Cu single atoms for the highly efficient reduction of CO 2 into CH 4 .