关键词: 二硫化钼, 还原氧化石墨烯, 水热, 催化剂, 催化加氢

Abstract:

MoS₂ catalysts supported on reduced graphene oxide (MoS₂/rGO) were synthesized through hydrothermal process. The nanostructure parameters including stacking layers, slab length, and dispersion were characterized by scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy and high-resolution transmission electron microscopy. The results indicated that the hydrothermal synthesis method could successfully load MoS₂ over the surface of rGO support, and adjust the catalytic active sites of MoS₂ by tuning the Mo precursors. Polycyclic aromatic hydrocarbon anthracene was used as the model compound of heavy oils to evaluate the catalytic hydrogenation performance of the MoS₂/rGO catalysts. The MoS₂/rGO-ATTM catalyst, synthesized with ammonium tetrathiomolybdate as Mo precursor by the hydrothermal method, demonstrated an extremely high anthracene hydrogenation conversion of 55.1% and a high selectivity to octahydroanthracene of 86.6%, which were respectively 2.0 times and 4.2 times as high as those of the IM-MoS₂/rGO catalyst synthesized by impregnation method. The catalytic hydrogenation activities of MoS₂/rGO catalysts were not related to their surface area, but depended on their stacking layers and slab lengths. The excellent catalytic activity of the MoS₂/rGO-ATTM catalyst may be ascribed to the high exposure of hydrogenation active sites, the enhanced dispersion of MoS₂ nanosheets in the catalyst, and the good suspension of the catalyst in the reaction mixture.

Key words: molybdenum disulfide(MoS₂), reduced graphene oxide, hydrothermal, catalyst, catalytic hydrogenation