Structural and Optical Studies on WO3/SnO2 and WO3/SnO2/SrO Composites

Doping is a widely explored technique to modify the properties of semiconducting materials. In the case of tungsten trioxide (WO3), doping with elements such as SnO2 and SrO has garnered significant attention owing to its potential impact on structural, functional, and optical characteristics. We report on structural, functional, optical, and dielectric properties of SnO2/WO3 and SrO/SnO2/WO3 composites and, for comparison, WO3 prepared via a wet chemical method. Crystallite phases were confirmed using x-ray diffraction patterns. Fourier-transform infrared spectroscopy and dielectric studies were employed to analyze the functional groups, dielectric constants, and losses of the SnO2/WO3 and WO3/SnO2/SrO composites. Ultraviolet-visible spectroscopy and photoluminescence spectroscopy were used to examine the optical absorption and emission maxima, respectively. The energy bandgap was determined from the absorption spectra by using a Tauc plot. Additionally, all the prepared composites exhibited brighter and sharper narrow emissions in the photoluminescence spectra. Dielectric studies of WO3/SnO2/SrO composites revealed slightly better dielectric constants and lower dielectric losses than those of SnO2/WO3 composites. Our findings suggest that the prepared composites are suitable for use in sensor and optoelectronic device applications.