Research Article

Research on the photoelectrical properties of TiO₂-doped V₂O₅/FTO nanocomposite thin films under thermal and electrical excitation

¹ College of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, P.R. China
² Shanghai Key Laboratory of Modern Optical System, Shanghai 200093, P.R. China

^* Corresponding author: liyi@usst.edu.cn

Received: 25 October 2024
Accepted: 3 January 2025

Abstract

The TiO₂-doped V₂O₅/FTO nanocomposite thin films were prepared on the FTO substrates by sol-gel method and post-annealing process, and the MSM structural devices based on the prepared films were fabricated by sputtering, photolithography and etching techniques. SEM, XRD, and XPS were respectively used to study the morphology, structure and composition of the film, and the electrical and optical regulations of the device were measured by using spectrophotometry and semiconductor parameter analyzer. In the temperature range of 20–360 °C, the maximum modulation amplitude of the TiO₂-doped V₂O₅/FTO film in the 400–1600 nm band was 18.282% and the modulation of the V₂O₅/FTO film was increased by 9.663% after TiO₂-doping. The resistance of the FTO/V₂O₅-TiO₂/FTO device reduced by 3–4 orders of magnitude by comparing with the FTO/V₂O₅/FTO device. The FTO/V₂O₅-TiO₂/FTO device underwent semiconductor-metal state transition (SMT) around 259.91 °C. Under the applied voltage of 0–5 V, the maximum transmittance variations could reach 8.821%, 7.174% and 11.540% in 400–1600 nm band at the temperature of 20 °C, 40 °C and 80 °C, respectively. The outstanding optical and electrical regulation properties and the favorable cycling stability make the nanocomposite film expected to be applied in the field of optoelectronic devices.