Effect of CTAB Surfactant on Textural, Structural, and Photocatalytic Properties of Mesoporous WS₂

In this paper, we report the influence of CTAB surfactant on solvothermally obtained mesoporous tungsten disulfide (WS₂). The role of CTAB concentration in the formation of mesoporous WS₂ structure is demonstrated. The X-ray diffraction (XRD) analysis revealed the presence of hexagonal WS₂. The field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM) studies showed the formation of mesoporous WS₂ structure. At room temperature, the cations of CTA+ aggregated into mixed micelles with WS^2– precursors and acted as templates for the synthesis of mesoporous WS₂. The sample S4 with 0.2 mmol of CTAB surfactant had a BET surface area of around 217.6 m² g^–1. The calculated band gap energy of sample S4 is 1.41 eV. The photocatalytic activity was tested for the degradation of Rhodamie B (RhB) pollutant under UV light irradiation. It was found that sample S4 exhibited superior photocatalytic activity than that of sample S1, S2 and S3. The enhancement in the photocatalytic activity was attributed to large surface area. The textural, morphological and photocatalytic properties of mesoporous WS₂ were strongly influenced by concentration of surfactant. It is observed that the mesopore size increases with the molar concentration of CTAB.