Sepiolite-Supported WS₂ Nanosheets for Synergistically Promoting Photocatalytic Rhodamine B Degradation

Abstract

Pristine tungsten disulfide (WS2) nanosheets are extremely prone to agglomeration, leading to blocked active sites and the decrease of catalytic activity. In this work, highly dispersed WS2 nanosheets were fabricated via a one-step in situ solvothermal method, using sepiolite nanofibers as a functional carrier. The ammonium tetrathiotungstate was adopted as W and S precursors, and N,N-dimethylformamide could provide a neutral reaction environment. The electron microscope analysis revealed that the WS2 nanosheets were stacked compactly in the shape of irregular plates, while they were uniformly grown on the surface of sepiolite nanofibers. Meanwhile, the BET measurement confirmed that the as-prepared composite has a larger specific surface area and is more mesoporous than the pure WS2. Due to the improved dispersion of WS2 and the synergistic effect between WS2 and the mesoporous sepiolite mineral which significantly facilitated the mass transport, the WS2/sepiolite composite exhibited ca. 2.6 times the photocatalytic efficiency of the pure WS2 for rhodamine B degradation. This work provides a potential method for low-cost batch preparation of high-quality 2D materials via assembling on natural materials.

Keywords

• photocatalysis
• rhodamine B degradation
• sepiolite nanofibers
• catalyst support
• WS₂ nanosheets