Boosting CO₂ Electroreduction over a Cadmium Single-Atom Catalyst by Tuning of the Axial Coordination Structure

Guided by first-principles calculations, it was found that Cd single-atom catalysts (SACs) have excellent performance in activating CO₂, and the introduction of axial coordination structure to Cd SACs cannot only further decrease the free energy barrier of CO₂ reduction, but also suppress the hydrogen evolution reaction (HER). Based on the above discovery, we designed and synthesized a novel Cd SAC that comprises an optimized CdN₄S₁ moiety incorporated in a carbon matrix. It was shown that the catalyst exhibited outstanding performance in CO₂ electroreduction to CO. The faradaic efficiency (FE) of CO could reach up to 99.7 % with a current density of 182.2 mA cm⁻² in a H-type electrolysis cell, and the turnover frequency (TOF) value could achieve 73000 h⁻¹, which was much higher than that reported to date. This work shows a successful example of how to design highly efficient catalysts guided by theoretical calculations.