Pronounced effects of the nominal concentrations of WO₃ and Ag: WO₃ nano-plates (obtained by a co-precipitation method) on their structural, morphological and optical properties

Tungsten oxide and different concentration of silver (Ag)-doped tungsten oxide nano material were synthesized by co-precipitation technique. The functional vibrations, structure, and morphology of as-prepared nano material were studied by Fourier transmission infrared spectroscopy, X-ray diffraction, scanning electron microscopy (SEM) and High-resolution transmission electron microscopy (HR-TEM) techniques. The SEM and HR-TEM analysis revealed the formation of nano-plate/nano rods with an average diameter of 40-80 nm diameter and 1-1.5 mm length. Fluorescence (PL) and UV-visible absorption techniques have been used to study the optical properties of the prepared nanoparticles. The observed red shift in the visible absorption spectra confirmed the promoted electron-phonon interaction in WO₃ and Ag: WO₃ nanoparticles compared to bulk structures. The photoluminescence of nanocrystalline Ag²⁺ doped WO₃ exhibited a strong violet-blue, blue-green emission. Concentration dependence of the emission intensity of Ag²⁺ in WO₃ was studied, and the significant concentration was found to be 0.5% of Ag: WO₃. The effluent dye degradation executed for the 0.5% of Ag: WO₃ sample under the visible light which reveals the highest degradation efficiency in appropriate time. (orig.)