Thermoluminescence and photoluminescence analyses of MEH-PPV, MDMO-PPV and RU(bpy)3 gamma-irradiated polymer thin films
Por:
Ortiz-Morales A., Ortiz-Lopez J., Cruz-Zaragoza E., Gómez-Aguilar R.
Publicada:
1 ago 2015
Categoría:
Radiation
Resumen:
Effects of irradiation with 60Co gamma photons on poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(3',7' dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) and tris(2,2'-bipyridyl)dichlororuthenium(II) hexahydrate (Ru(bpy)3) thin films were analyzed regarding their thermoluminescence (TL) and photoluminescence (PL) properties. A linear TL dose response was obtained from the MEH-PPV and MDMO-PPV polymer films in dose ranges of approximately 0.170-4.08kGy and 0.170-0.850kGy, respectively, followed by a supralinear behavior. A dependence on the conjugation length of the polymer chains which was favored by heating of the film, was observed, and irradiation generated a blue-shift in MEH-PPV and Ru(bpy)3. Furthermore, the PL structure was not modified. The most likely effect involved in the TL emission was trapping. The high activation energy values of the traps in the TL may be attributed in part to the binding energy of the exciton. A deconvolution process was carried out to obtain the kinetic parameters from the TL glow curves and PL spectra. © 2015 Elsevier Ltd.
Filiaciones:
Ortiz-Morales A.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, Unidad Irradiac & Seguridad Radiol, Mexico City 04510, DF, Mexico
Unidad Profesional Interdisciplinaria de Ingeniería y Tecnologías Avanzadas, IPN, Av. Instituto Politécnico Nacional 2580, México D.F., 07340, Mexico
Unidad de Irradiación y Seguridad Radiológica, Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, México D.F., 04510, Mexico
Ortiz-Lopez J.:
Escuela Superior de Física y Matemáticas, IPN, Av. Instituto Politécnico Nacional s/n, México D.F., 07738, Mexico
Cruz-Zaragoza E.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, Unidad Irradiac & Seguridad Radiol, Mexico City 04510, DF, Mexico
Unidad de Irradiación y Seguridad Radiológica, Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, México D.F., 04510, Mexico
Gómez-Aguilar R.:
Unidad Profesional Interdisciplinaria de Ingeniería y Tecnologías Avanzadas, IPN, Av. Instituto Politécnico Nacional 2580, México D.F., 07340, Mexico
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