Enhanced Photocatalytic activities of TiO2 through Metal chalcogenides based Nanocomposites (ZnS/TiO2) for Methylene Blue degradation

We report the photocatalytic activity of ZnS/TiO2 nanocomposite synthesized through a one-step hydrothermal method. The effect of ZnS concentration on the phase and morphology of coupled materials was investigated. Xray diffraction (XRD) confirms the phase purity and formation of the tetragonal structure of anatase phase TiO2. From the UV-Visible spectra, it is found that the increase in ZnS concentration enhances the absorption towards higher wavelength. The surface morphology as revealed by Transmission electron microscope (TEM) shows the formation of the mesoporous structure of TiO2. The presence of ZnS deposited on the mesoporous structure of TiO2 was further confirmed through elemental (EDX) analysis. The surface area of ZST1 is found to be 236.23 m2/g as measured by Brunauer Emmett-Teller (BET) analysis. The addition of ZnS prevents the aggregation of TiO2 and promotes the carrier transfer efficiency, high electron mobility and thus enhancing the photocatalytic activity. The highest degradation efficiency was found to be 93 % of methylene blue (MB) solution after 60 minutes under visible light irradiation.

Automated summary

We synthesized ZnS/TiO2 nanocomposite through a one-step hydrothermal method and studied the effect of ZnS concentration on the phase and morphology of the materials. XRD confirmed the formation of tetragonal structure of anatase phase TiO2. UV-Visible spectra showed increased absorption towards higher wavelength with higher ZnS concentration. TEM revealed the formation of mesoporous structure of TiO2 and EDX analysis confirmed the presence of ZnS on the surface. The addition of ZnS prevented TiO2 aggregation and enhanced photocatalytic activity, achieving a highest degradation efficiency of 93% for methylene blue solution under visible light irradiation after 60 minutes.