Photoconductivity studies on amorphous and crystalline TiO2 and TiO2:Eu3+ thin films synthesized by sol-gel
Por:
Francisco-Santiago P., García-Macedo J.A., Valverde-Aguilar G.
Publicada:
1 ene 2012
Resumen:
Amorphous and crystalline TiO2 and TiO2:Eu 3+ 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, scanning electron microscopy and transmission electronic microscopy and UV-Vis absorption spectroscopy. An anatase phase was determined in the samples calcined at 500°C. Film thickness was calculated by SEM. Absorption peaks were located between 293-298 nm which are due to the titania host. It can be observed that this peak position depends of the 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 with curve lines to order square at darkness and under illumination (310 nm and 515 nm). This indicates a non-ohmic behavior. Transport parameters, photovoltaic and photoconductive; were calculated for both samples. © 2012 SPIE.
Filiaciones:
Francisco-Santiago P.:
Departamento de Estado Sólido, Instituto de Física, Universidad Nacional Autónoma de México, México D.F. C.P. 04510, Mexico
García-Macedo J.A.:
Departamento de Estado Sólido, Instituto de Física, Universidad Nacional Autónoma de México, México D.F. C.P. 04510, Mexico
Valverde-Aguilar G.:
CICATA Unidad Legaria, Instituto Politécnico Nacional, Legaria 694, Col Irrigación, Miguel Hidalgo, 11500 Ciudad de México, Distrito Federal, Mexico
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