Single-Atom Transition Metals Anchored NbS 2 : Electrocatalytic Reduction of CO 2 to HCOOH

The design and synthesis of highly stable single-atom catalysts (SACs) are key challenges in enhancing the electrocatalytic carbon dioxide reduction reaction (CO2RR). Two-dimensional material-supported SACs have received extensive attention due to their own characteristics, such as stability and activity. However, developing stable and efficient electrocatalysts remains a critical challenge in the electrocatalytic reduction of CO2 to formic acid (HCOOH). Based on first-principles calculations, we systematically investigate the catalytic performance of the six single-atom transition metals (TM = Ti, V, Mn, Y, Zr, Hf) anchored on monolayer niobium disulfide (TM@NbS2) as novel catalysts of the CO2RR in this work. The Mn@NbS2, V@NbS2, and Y@NbS2 catalysts demonstrate efficient catalytic reduction of CO2 to HCOOH. In particular, the Mn@NbS2 catalyst exhibits the lowest limiting potential of −0.53 V for HCOOH production among the studied TM@NbS2 systems. Compared with the hydrogen evolution reaction (HER), the Mn@NbS2 catalyst demonstrates superior selectivity toward the CO2RR. Therefore, the Mn@NbS2 catalyst is a promising candidate for the electrocatalytic reduction of CO2 to HCOOH. This work may be helpful for the development of high-efficiency NbS2-based electrocatalysts.