Bifunctional WO3-AgInS2 nanocomposite material: Enhanced electrical property and photocatalytic activity for degradation of methylene blue dye under visible-light irradiation

Nanocomposite material based on WO3-AgInS2 with different weight percentages of AgInS2 is synthesized using solid-state reaction method. Several analytical methods confirm that the heterostructure WO3-AgInS2 nanocomposite can be used as an electric material as well as a photocatalyst for the degradation of methylene blue (MB) dye under visible light. X-Ray diffraction, Scanning Electron Microscopy-Energy Dispersive X-ray, Transmission Electron Microscopy, and UV-Diffuse Reflectance spectroscopy were used to characterize the synthesized nanocomposites. AC Impedance measurements show that the addition of the semiconductor AgInS2 suppresses electronic conductivity and increases the ionic conductivity compared to pure WO3. Nanocomposite containing 20 wt. % AgInS2 (20-WAIS) was found to have higher ionic mobility, with ionic conductivity of 1.00×10−2 Scm−1 at ambient temperature and bulk resistance of 7.50 Ω. The most effective photocatalytic activity for MB decolorization was shown by 20-WAIS nanocomposite and 97 % degradation of MB was achieved within 50 min of visible-light illumination. The enhanced photocatalytic activity might be the result of a direct Z-Scheme mechanism that maintains charge separation ability throughout time. 20-WAIS nanocomposite exhibits structural and morphological changes that are very significant to the increase of conductivity and outstanding photocatalytic activity. Energy and environmental concerns may be addressed and alleviated as a result of the research undertaken in the present study. [Display omitted]