Direct synthesis of TiO2-supported MoS2 nanoparticles by reductive coprecipitation

Molybdenum disulfide nanoparticles supported on titania were synthesized from aqueous solutions containing Ti and Mo precursor salts by an in situ redox reaction. The synthesis involves a redox process between Ti3+ and MoS42−, which proceeds readily under mild conditions in aqueous solution. Catalysts were made in a single step, yielding amorphous catalysts with high Mo content, or in two steps to obtain MoS2 supported on well-defined TiO2 with lower Mo content. Catalysts obtained by single-step reductive coprecipitation were highly active in the hydrodesulfurization of dibenzothiophene, exceeding the activity of an alumina-supported Co–Mo reference. In contrast to alumina-supported catalysts, the addition of Co as promoter did not enhance the catalytic activity of MoS2/TiO2 to the same extent (+30 %) as for alumina-supported Co–Mo catalysts. Instead, a change in selectivity towards hydrogenolysis products at the expense of hydrogenation products was observed. It is suggested that Ti may act as a promoter for MoS2 in hydrogenation reactions.