Enhancing the optoelectronic properties of V2O5 thin films through Tb doping for photodetector applications

Using highly economical and scalable nebulizer-aided spray pyrolysis approach, a high-quality terbium (Tb) doped vanadium pentoxide (V2O5) thin film-based optical sensor was developed. To investigate the effects of various terbium doping concentrations on its growth and optoelectronic features, the structural prop-erties as well as its elemental composition, surface morphology, photoluminescence, optical, and current-voltage (I-V) characteristics were examined. An orthorhombic structure with orientation along the (010) plane was found to be existing in the X-ray diffraction pattern of Tb-doped V2O5 thin films with increase in the crystallite size upto 3 % Tb-doped V2O5 films. The prevalence of dense nanorods is observed in all the films while analyzing their micrograph from a field emission scanning electron microscope. Also it is noted that the addition of 3 % Tb dopants increases UV absorption by lowering its energy gap from 2.43 to 2.37 eV. A strong green emission peak at 530 nm and weak UV bands were noted in the PL spectrum due to higher crystalline quality, free from defects and native flaws for the 3% Tb-doped V2O5. Terbium-doped V2O5 films exhibited elevated UV photo response and photoelectric properties than their pristine form. Among various doping concentrations, 3 % terbium in V2O5 thin film exhibited a maximum response (4.72 x 10-1 A/W), detectivity (7.82 x 1010 Jones), external quantum efficiency (110 %), and high photo-switching character-istics. This study confirms the optimal 3 % Tb dopant concentration plays a significant role in enhancing the UV-visible photo-sensing behavior of the V2O5 thin films. Data availability statement: The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.(c) 2023 Elsevier B.V. All rights reserved.