On the incorporation of nickel and cobalt into MoS₂-edge structures

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• 作者：Sun ; Mingyong ; Nelson ; Alan E. ; Adjaye ; John
• 关键词：Molybdenum sulfide ; Nickel-promoted molybdenum sulfide ; Cobalt-promoted molybdenum sulfide ; Hydrotreating ; Density-functional theory
• 刊名：Journal of Catalysis
• 出版年：2004
• 出版时间：August 15, 2004
• 年：2004
• 卷：226
• 期：1
• 页码：32-40
• 全文大小：426 K

文摘

The present study investigates the details of MoS₂-edge surfaces modified with different loadings of nickel and cobalt using density-functional theory (DFT) under generalized gradient approximation (GGA) considering the effect of sulfidation conditions. Although this has been the subject of previous studies, a comprehensive understanding of the promoted edge surfaces is not complete. Under typical sulfidation conditions, nickel prefers to incorporate into the metal edge and cobalt the S-edge of MoS₂. On a partially promoted metal edge surface, sulfur atoms bond to the surface on top of the molybdenum atoms and the promoter atoms tend to be uncovered. The adsorbed sulfur atoms atop of molybdenum atoms and the neighboring uncovered promoter atoms provide pairs of base (or nucleophile) and acid sites for surface catalytic reactions.