Coordination Environment Engineering to Regulate the Adsorption Strength of Intermediates in Single Atom Catalysts for High-performance CO₂ Reaction Reduction

The modulation of the coordination environment of single atom catalysts (SACs) plays a vital role in promoting CO₂ reduction reaction (CO₂RR). Herein, N or B doped Fe-embedded graphyne (Fe-GY), Fe-nXGYm (n = 1, 2, 3; X = N, B; m = 1, 2, 3), are employed as probes to reveal the effect of the coordination environment engineering on CO₂RR performance via heteroatom doping in SACs. The results show that the doping position and number of N or B in Fe-GY significantly affects catalyst activity and CO2RR product selectivity. In comparison, Fe-1NGY exhibits high-performance CO₂RR to CH₄ with a low limiting potential of −0.17 V, and Fe-2NGY3 is demonstrated as an excellent CO₂RR electrocatalyst for producing HCOOH with a low limiting potential of −0.16 V. With applied potential, Fe-GY, Fe-1NGY, and Fe-2NGY3 exhibit significant advantages in CO₂RR to CH₄ while hydrogen evolution reaction is inhibited. The intrinsic essence analysis illustrates that heteroatom doping modulates the electronic structure of active sites and regulates the adsorption strength of the intermediates, thereby rendering a favorable coordination environment for CO₂RR. This work highlights Fe-nXGYm as outstanding SACs for CO₂RR, and provides an in-depth insight into the intrinsic essence of the promotion effect from heteroatom doping. © 2024 The Authors. Small published by Wiley-VCH GmbH.