Elucidating the layer-number impact of MoS2 on the adsorption and hydrogenation of CO

MoS 2 is an attractive sulfur-resistant catalyst for directly converting sulfur-containing syngas to high value-added chemicals. However, the effect of the layered structure on the catalytic activity for CO hydrogenation reactions is far from clear. Herein, MoS 2 /carbon composite catalysts with 1–8 stacking layers in MoS 2 crystallites are synthesized, and the impact of the layer numbers on the catalytic performance is probed for the low-temperature methanation of sulfur-containing syngas. The results indicate that the turnover frequency of CO methanation increases from 2.4 × 10 -3 to 3.7 × 10 -3 s −1 with decreasing layer numbers of MoS 2 crystallites from 8.3 to 1.1. This result is thoroughly explained by the fact that the higher ratio of rim sites in MoS 2 crystallites with fewer layer numbers enhances the catalytic activity, which originates from the facilitated activation of CO and H 2 . These understandings are important for the rational design and development of more efficient MoS 2 -based catalysts for CO hydrogenation.