The catalytic mechanism of CO2 electrochemical reduction over transition metal-modified 1T'-MoS2 monolayers

Abstract

Recently, typical transition metal disulfides (e.g. MoS2 in the 2H phase), have attracted tremendous attentions for catalyzing CO2 reduction reaction (CO2RR), but the potential catalytic performance of MoS2 in the conducting 1T' phase for CO2RR has rarely been reported. Inspired by the high catalytic activity of low-dimensional single-atom catalysts for CO2RR and the enhanced stability of 1T'-MoS2 when embedded transition metals, herein, the catalytic mechanisms of transition metal-modified 1T'-MoS2 monolayers (denoted as TM@1T'-MoS2, where TM is 3d-5d transition metals except Y, Tc, Cd, Hg and La-Lu) in reducing CO2 to CH4 have been systematically investigated via the first-principles calculations. The results show that compared to pristine 1T'-MoS2, embedding transition metals can enrich the varieties of the CO2RR products. Among the considered catalysts, we find that Ru@1T'-MoS2 and Pt@1T'-MoS2 can catalyze CO2 reduction to CH4 and CH3OH with acceptable limiting potentials of -0.56 and -0.73 V, respectively. Besides, Re@1T'-MoS2 and Zn@1T'-MoS2 are considered to be the promising catalysts for HCOOH generation with the ultralow limiting potentials of -0.13 and -0.22 V, respectively. This work will provide useful insights to guide the design of TMD-based catalysts.