The Impact of TiO 2 - Doped V 2 O 5 Films on the Structural, Linear and Nonlinear Optical Behavior for Optoelectronic Applications

Abstract

By the dip-coating method, composite films of titanium oxide-doped vanadium pentoxide (TVPO) in different compositional ratios were created. X-ray diffraction and TEM data indicate that TVPO films at any compositional ratio of TiO2 produce xTiO2-100−x V2O5, a substitutional solid solution where 0≤x≤5. Employing double-beam UV-VIS spectrophotometers, the optical properties of the created TiO2-doped V2O2 nanocrystalline films, including their transmittance, absorbance, and reflectance, were investigated. The nanocrystalline-formed films exhibit good transparency in the Visible region (550 - 900 nm). Urbach band tail energy, the refractive index, parameters of dispersion energy using the Wemple and DiDomenico (WDD) single-oscillator model, nonlinear refractive index, and first and third optical susceptibilities were also estimated. It was found that by comparing the observed linear and nonlinear optical properties in TiO2-doped films to pure V2O5, the doped films revealed smaller optical bandgaps of about 2.2 eV where the pure V2O5 is around 2.4 eV, suggesting the possibility of a variety of optical applications. As the TiO2 concentration rises, the absorption coefficient marginally increases. This is explained by the increasing lattice distortion brought on by the growing crystallite size, as shown by the XRD. It was discovered that the indirect permitted type transition mechanism had an expanding optical band gap Eop concerning the TiO2 concentration. By supposing a hydrogen-like model, the carrier’s contents N was presumed. The present research demonstrates that TiO2 doping significantly affects the optical and structural characteristics of V2O5 films, making them intriguing materials for a range of uses, including nonlinear optical applications and optoelectronic devices.