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.