Enhancing the optical, temperature-dependent electrical and dielectric properties of WO3 through Fe doping for optoelectronic applications

WO3 nanoparticles doped with various Fe concentrations were prepared via acid-assisted precipitation method. The XRD patterns confirmed the monoclinic arrangement, and the crystallite size decreased on increasing the dopant concentration. The surface characterizations performed using SEM images and the EDS spectra exposed the particle size and effective doping of Fe3+ ions within the host lattices of WO3. The local structure and crystal quality were studied by FTIR and Raman spectra. From the absorption spectra, doping of Fe decreases the optical band-gap energy and a rise in Urbach energies. The increase in green emission intensities of photoluminescence spectra reveals the increasing oxygen vacancies in WO3 after doping. The temperature-dependent AC and DC conductivities were enhanced on increasing the Fe concentration. The dielectric parameters were elucidated on the basis of Maxwell-Wagner theory which depends on dopant composition. On the whole, the electrical properties of WO3 can be improved by doping with Fe ions.