Computational study of nitrogen-doped vanadium disulfide-loaded single-atom catalysts for the electrocatalytic reduction of CO2

The electrocatalytic reduction of CO2 using single-atom catalysts (SACs) has significant potential to make a substantial impact on energy regeneration and greenhouse effect control in the future. The novel SACs were designed based on the properties of vanadium disulfide (VS2) nanosheets with large surface area and unique electronic structure, and the outstanding catalytic performance of transition metal atoms bonding with nitrogen atoms for CO2 reduction reaction (CO2RR). In this work, the electrocatalytic performance of N-doped vanadium disulfide nanosheets loading a series of transition metal single atoms for CO2RR was systemically evaluated by density functional theory (DFT). The results showed that TM@N3-VS2 (TM = Ti, V, Cr, Mn, Zr, Nb, Mo, Ru, Rh) possess excellent performance for reduction of CO2 to CH4, with low limiting potential of 0.36 eV, 0.28 eV, 0.2 eV, 0.34 eV, 0.54 eV, 0.33 eV, 0.55 eV, 0.38 eV, and 0.25 eV, respectively. The calculation results indicated that the nitrogen atoms could adjust the coordination environment of transition metal atoms and modulate the ability of transition metal atoms and VS2 nanosheets accepting and donating electrons, which makes CO2 adsorb on TM@N3-VS2 with moderate adsorption energy, and significantly reduces the reaction energy barrier.