Preparation of V2O5 thin film by sol-gel method and its photoelectric properties during thermally induced phase transition

Abstract:Here a high quality V₂O₅ film was prepared on quartz substrate by sol-gel spin coating method,which was then post-annealed. Its optical and electrical properties were studied during thermally induced phase transition. The crystal structure and morphology of the V₂O₅ film were analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM). And the composition of the V₂O₅ film was analyzed by XPS patterns.The optical, electrical properties and phase transition of the V₂O₅ film were characterized under different bias voltages and temperatures. The results show that the optical transmittance of the V₂O₅ film is 60% from 300 to 2000 nm at room temperature. There is an obvious change in the optical transmittance during the phase transition.When temperature is higher than 231°C,the near-infrared transmittance of V₂O₅ film from 900 to 1600 nm is averagely reduced by 18% with resistance changes by 3 orders of magnitude.The thermal hysteresis loops also shows that the film has good photoelectric properties during the reversible phase transition.
Keywords:V₂O₅ film;sol-gel;thermotropic phase transition;optical transmittance;resistance