Carbon‐Limited Conversion of Molybdenum Carbide into Curved Ultrasmall Monolayer Molybdenum Disulfide under Effects of ZrO₂ Crystal Phases for Efficient Sulfur‐Resistant Methanation

Abstract

MoS2 has been regarded as a highly active catalyst for the sulfur‐resistant methanation because of its abundant active sites on defect and edge sites. A challenging problem is how to increase the density of the intrinsic active sites. It is a reasonable method to increase more active sites toward CO methanation by preparing ultrasmall monolayer molybdenum disulfide and curving them. Therefore, highly active ultrasmall and curved monolayer MoS2/ZrO2 catalysts are fabricated via carbon‐limited conversion Mo2C species in H2S atmosphere. The physical and chemical properties of the supports and catalysts were characterized by X‐ray diffraction, N2‐Physisorption, Raman spectroscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, and thermogravimetric. The results indicate that amorphous carbon on monoclinic zirconia (M−ZrO2) is the key for the formation of such MoS2 structure. The sulfided Mo2C/M−ZrO2 catalyst displays superior sulfur‐resistant methanation activity and stability compared with sulfided Mo2C/tetragonal zirconia (T−ZrO2), ascribed to curved ultrasmall monolayer MoS2 well dispersed on M−ZrO2 with more active sites. This synthetic strategy provides a new method for the preparation of well‐dispersed monolayer molybdenum disulfide catalysts.