Sulphide catalysts on silica as a support

Yermakov, Yu. I.; Startsev, A. N.; Бурмистров, В. А.; Shumilo, O. N.; Bulgakov, N. N.

doi:10.1016/s0166-9834(00)80297-3

Cited by 32 publications

(8 citation statements)

References 48 publications

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“…It has been shown experimentally, in surface science type experiments and by thermo-chemistry calculations, that the removal of S atoms from a MoS 2 slab starts from the edges. 37,45 Theoretical calculations show that this removal starts with the terminal S atoms originally bound on the 2-fold unsaturated Mo atoms, for example in our case, on the (101 h0) edges (that we called "reduced"). These terminal S atoms could be removed even by molecular hydrogen, but this is much easier in the presence of activated hydrogen.…”

Section: Discussionmentioning

confidence: 82%

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄

Delmon

Pang

2000

J. Phys. Chem. A

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It is shown that ab initio MO approaches are suitable to simulate the relatively large hexagonal MoS 2 slab corresponding to the average initial size (15-20 Å) of MoS 2 on alumina-supported catalysts used in hydrodesulfurization (HDS) and hydrogenation (HYD) of petroleum fractions. By using a general ab initio MO program, GAMESS, the structure optimization of the Mo 27 S 54 slab is possible at the UHF/MINI/ECP)SBK level of theory, providing helpful information on the structural and electronic properties of the slab. The improvement, compared to other theoretical calculations based on simplified structural models, is that the different bonding and electronic properties of the Mo and S atoms in basal plane and on different edges and corners of the slab can clearly be distinguished. The structure of the slab is relaxed toward the edges. The 2-fold coordinatively unsaturated sites (CUS) on corners have both electron-donating and -accepting properties, making them potentially active for HDS (and HYD) reactions. The 2-fold CUS's on the edges ("reduced edges") seem to permit only the HYD reaction or CO hydrogenation. The removal of the basal plane S atoms requires activated atomic hydrogen species. The unreduced (1 h010) edges do not seem to be potentially active catalytically. This deepens the understanding of the catalytic nature of the MoS 2 structure for several reactions, especially HDS and HYD (hydrotreating reactions) and CO hydrogenation.

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Section: Discussionmentioning

confidence: 82%

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄

Delmon

Pang

2000

J. Phys. Chem. A

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“…At high cobalt content, the Co 9 S 8 phase is formed. 276 In Ni7Mo7S and Ni7W7S catalysts, the phase NiS was also observed along with mixed phases. 277 According to NMR and EXAFS data, the major active phase of a molybdenum sulfide catalyst consists of MoS 2 plates with Mo coordination number 4 or 5 and with the Co atoms at their edges.…”

Section: Almentioning

confidence: 93%

Heterogeneous hydrogenation catalysts

Navalikhina¹,

Крылов²

1998

Russ. Chem. Rev.

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“…1, it is found there are two types of edge (i.e. (1 01 0) and (1 0 1 0)) on the Mo 27 S 54 cluster [5,27]. Surface science experimental results and theoretical calculations have shown that the formation of CUS with the removal of S starts with the terminal S atoms on the (1 01 0) and (1 0 1 0) edges [28][29][30].…”

Section: Discussionmentioning

confidence: 97%

“…In these dispersed particles, the boundaries in all directions are believed to provide the high intrinsic activity for HDS reaction. Furthermore, it has been shown experimentally that the removal of S atoms from a MoS 2 slab starts from the edge on which the formed CUS has strong adsorption affinity for thiophene and H 2 S and is responsible for the thiophene HDS [5,6]. Although it is easy to form 2-fold CUS on the (1 0 1 0) edge of MoS 2 even under the atmosphere of H 2 , the 2-fold CUSs may not activate the thiophene to the degree of cleaving S C bond of thiophene [7,8].…”

Section: Introductionmentioning

confidence: 99%

Formation and adsorption properties of the bridging sulfur vacancies at the (1¯ 0 1 0) edge of Mo27S(54−x): A theoretical study

Fan

Delmon

et al. 2006

Journal of Molecular Catalysis A: Chemical

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Sulphide catalysts on silica as a support

Cited by 32 publications

References 48 publications

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄

Heterogeneous hydrogenation catalysts

Formation and adsorption properties of the bridging sulfur vacancies at the (1¯ 0 1 0) edge of Mo27S(54−x): A theoretical study

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Sulphide catalysts on silica as a support

Cited by 32 publications

References 48 publications

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS2 Slab: Mo27S54

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS2 Slab: Mo27S54

Heterogeneous hydrogenation catalysts

Formation and adsorption properties of the bridging sulfur vacancies at the (1¯ 0 1 0) edge of Mo27S(54−x): A theoretical study

Contact Info

Product

Resources

About

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄

Ab Initio Study of the Structural and Electronic Properties of a Real Size MoS₂ Slab: Mo₂₇S₅₄