Surfactant-assisted hydrothermally synthesized MoS2 samples with controllable morphologies and structures for anthracene hydrogenation

Abstract

MoS2 samples with controllable morphologies and structures were synthesized using surfactant-assisted hydrothermal processes. The effects of surfactants (PEG, PVP, P123, SDS, AOT, and CTAB) on the morphologies and structures of MoS2 samples were investigated. The results revealed that spherical, bulk-like, and flower-like MoS2 particles assembled by NH4+-intercalated MoS2 nano-sheets were synthesized. The morphologies of the MoS2 samples and their structures (including the slab length and the number of stacked layers) of MoS2 nano-sheets in these samples could be controlled by adjusting the surfactants. Mono-dispersed spherical MoS2 particles could be synthesized with PEG via the creation of MoS2 nano-sheets with slab lengths shorter than 15 nm and fewer than six stacked layers. Possible formation mechanisms of these MoS2 samples created via surfactant-assisted hydrothermal processes are proposed. Further, the catalytic activities of MoS2 samples for anthracene hydrogenation were evaluated in a slurry-bed reactor. The catalyst synthesized with the surfactant PEG exhibited the highest catalytic hydrogenation activity. Compared with the other catalysts, it had a smaller particle size, mono-dispersed spherical morphology, shorter slab length, and fewer stacked layers; these were all beneficial to exposing its active edges. This work provides an efficient approach to synthesize transition metal sulfides with controllable morphologies and structures.