Efficient electrocatalytic CO2 reduction on Ti3C2O2 surfaces: The effect of single-atom TM anchoring on product selectivity

Electrocatalytic CO2 reduction reaction (CO2RR) can transform CO2 into high-value-added chemicals, which is a key step toward alleviating greenhouse gas emissions and achieving carbon neutrality. Therefore, we constructed a transition metal single-atom catalyst anchored on Ti3C2O2 (TM-Ti3C2O2) through theoretical calculation. The results show that TMs are stable and capable of activating CO2. The embedding of TM breaks the symmetry of Ti3C2O2, causing different degrees of charge distribution of TM and distinct selectivity to CH4 products. CoTi3C2O2 is the optimum candidate for producing CH4 with limiting potential of -0.21 V. We established a linear relationship between the activity descriptor and the limiting potential of the product, which provided a method for screening efficient TMs. With applied potential, Co, Sc, and V-Ti3C2O2 exhibited great advantages in the CO2RR to CH4. This research serves as a point of reference for industrial production and helps to achieve the objective of carbon peaking more efficiently.