Carbon‐Limited Conversion of Molybdenum Carbide into Curved Ultrasmall Monolayer Molybdenum Disulfide under Effects of ZrO2 Crystal Phases for Efficient Sulfur‐Resistant Methanation. Issue 13 (6th June 2019)

• Record Type: Journal Article
• Authors: Zhao, Jun; Wang, Baowei; Yu, Wenxia; Li, Zhenhua; Xu, Yan; Ma, Xinbin
• Is Part Of: ChemCatChem. Volume 11:Issue 13(2019)
• Page Start: 3046
• Page End: 3053
• Publication Date: 2019-06-06
• Subjects: monolayer molybdenum sulfide -- molybdenum carbide -- amorphous carbon -- graphite carbon -- ZrO2 crystal phases; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201900648
• Languages: English
• ISSNs: 1867-3880

Abstract

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 Mo2 C species in H2 S 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 Mo2 C/M−ZrO2 catalyst displays superior sulfur‐resistant methanation activity and stability compared with sulfided Mo2 C/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. Abstract : Limited conversion . In this work, monolayer MoS2 catalysts supported on monoclinic ZrO2 (M−ZrO2 ) are prepared via carbon‐limited conversion Mo2 C species in H2 S atmosphere. Meanwhile, the sulfurized Mo2 C catalyst supported on tetragonal ZrO2 (T−ZrO2 ) was also prepared but no monolayer MoS2 was formed. As a result, monolayer MoS2 supported on M−ZrO2 (S−Mo2 C/M−ZrO2 ) shows highly activity and stability in sulfur‐resistant methanation.