Photoconductivity and stabilization of dopamine embedded in sol-gel TiO2 matrix
Por:
Prado-Prone G., Valverde-Aguilar G., Garcia-Macedo J., Vergara-Aragón P.
Publicada:
1 ene 2012
Resumen:
This work reports the synthesis of amorphous TiO2 matrix by sol-gel method at atmospheric conditions. DA was encapsulated in a TiO 2 matrix to reduce its chemical instability. To TiO2/DA sample was added the 15C5 to diminish the oxidation process. The stabilization process was followed by absorption spectra, colour change and infrared spectroscopy. Oxidation processes of the DA were identified by the presence of DA-quinone and DA-chrome. The TiO2/DA complex retarded the oxidation process for 30 days, while the TiO2/DA/15C5 complex this period was extended for 47 days. Photoconductivity studies were performed on both kinds of samples to analyze their charge transports. The experimental data were fitted with straight lines at darkness and under illumination at 320 nm, 400 nm, and 515 nm. This indicates an ohmic behavior. Transport parameters were calculated. The conductive effect is stronger under darkness than under illumination at 320 nm because the oxidation process in the darkness is less intense than under illumination. © 2012 SPIE.
Filiaciones:
Prado-Prone G.:
Department of Solid State, 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
Garcia-Macedo J.:
Department of Solid State, Instituto de Física, Universidad Nacional Autónoma de México, México D. F., C. P. 04510, Mexico
Vergara-Aragón P.:
Physiology Department, Faculty of Medicine, Universidad Nacional Autónoma de México, México D. F., C. P. 04510, Mexico
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