Photoconductivity studies on amorphous and crystalline TiO2 and TiO2:Eu3+ thin films synthesized by sol-gel

摘要

Amorphous and crystalline TiO2 and TiO2:Eu3+ thin films were synthesized by the sol–gel process at room temperature. The films were spin-coated on glass substrates. The samples were calcined at 400°C, 500°C for 2h to produce crystalline films. The films were characterized using X-ray diffraction, infrared spectroscopy, scanningelectron microscopy and transmission electronic microscopy and UV-Vis absorption spectroscopy. An anatase phasewas determined in the samples calcined at 500°C. Film thickness was calculated by SEM. Absorption peaks werelocated between 293-298 nm which are due to the titania host. It can be observed that this peak position depends ofthe calcination temperature. Band gap was calculated, and it indicates a non-linear behavior of the samples.Photoconductivity studies were performed on amorphous and crystalline films. The experimental data were fitted withcurve lines to order square at darkness and under illumination (310 nm and 515 nm). This indicates a non-ohmicbehavior. Transport parameters, photovoltaic and photoconductive; were calculated for both samples.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.