Spectroscopy of Indirect and Direct Bandgap Semiconductor for Tungsten Trioxide Nanoparticles

The aim of this paper is to synthesize WO3 direct band gap nanoparticles. As it is an issue that WO3 is an indirect band gap materiel; it only shows direct band gap properties when there is quantum confinement effect. Various samples were prepared using various concentrations with various stabilized concentration. The Structural properties of all samples were characterized using XRD and Raman. SEM images showed spheroid porous WO3. UV-visible spectroscopy and Photo luminescent studies were performed to analyze its optical properties. Results confirmed the formation of WO3 nanoparticles as confirmed by XRD. UV-Visible spectroscopy calculated the band gap in both indirect and direct case 2.8 eV and 4.6 eV respectively. Quantum confinement effect is confirmed by by both PL and UV-visible Spectroscopy.