Nanostructured TiO₂ Sensitized with MoS₂ Nanoflowers for Enhanced Photodegradation Efficiency toward Methyl Orange

Nanostructured titanium dioxide (TiO₂) has a potential platform for the removal of organic contaminants, but it has some limitations. To overcome these limitations, we devised a promising strategy in the present work, the heterostructures of TiO₂ sensitized by molybdenum disulfide (MoS₂) nanoflowers synthesized by the mechanochemical route and utilized as an efficient photocatalyst for methyl orange (MO) degradation. The surface of TiO₂ sensitized by MoS₂ was comprehensively characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence spectroscopy (PL), Brunauer-Emmett-Teller (BET) surface area, and thermogravimetric analysis (TGA). From XRD results, the optimized MoS₂-TiO₂ (5.0 wt %) nanocomposite showcases the lowest crystallite size of 14.79 nm than pristine TiO₂ (20 nm). The FT-IR and XPS analyses of the MoS₂-TiO₂ nanocomposite exhibit the strong interaction between MoS₂ and TiO₂. The photocatalytic results show that sensitization of TiO₂ by MoS₂ drastically enhanced the photocatalytic activity of pristine TiO₂. According to the obtained results, the optimal amount of MoS₂ loading was assumed to be 5.0 wt %, which exhibited a 21% increment of MO photodegradation efficiency compared to pristine TiO₂ under UV-vis light. The outline of the overall study describes the superior photocatalytic performance of 5.0 wt % MoS₂-TiO₂ nanocomposite which is ascribed to the delayed recombination by efficient charge transfer, high surface area, and elevated surface oxygen vacancies. The context of the obtained results designates that the sensitization of TiO₂ with MoS₂ is a very efficient nanomaterial for photocatalytic applications.