Three-dimensional (3-D) thermoluminescence (TL) spectra of Eu3-:YVO4, Eu3+:YV0.4P0.6O4 and Eu3+:Ce:YPO4 powders irradiated by X-rays were studied in the temperature range 30-350°C. The powders were reacted by a special hydrolyzed colloid reaction (HCR) technique at ∼ 80°C and were subsequently fired at 800°C. The glow curves possess two major peaks indicating different defect structures. The first TL peak was observed at ∼ 85°C and represents defects in the anion sublattice. It was increased by extended firing and colloidization processes and by substituting PO3-4 for the VO3-4 anion. The second TL peak was found at 135°C and is generated by impurity defects in the cation site of an yttrium orthovanadate-phosphate system. It was identified by the assistance of the Ce dopant. In Eu3+:Ce:YPO4 the predominance of one of above-mentioned defect structures can be changed by a suitable selection of HCR parameters, thus obtaining high emission intensities caused by two orders of magnitude lower X-ray radiation levels than those used for the orthovanadates.
Erdei, S., Kovács, L., Martini, M., Meinardi, F., Ainger, F., White, W. (1996). High temperature 3-D thermoluminescence spectra of Eu3+ activated YVO4 - YPO4 powder systems reacted by hydrolyzed colloid reaction (HCR) technique. JOURNAL OF LUMINESCENCE, 68(1), 27-34 [10.1016/0022-2313(95)00085-2].
High temperature 3-D thermoluminescence spectra of Eu3+ activated YVO4 - YPO4 powder systems reacted by hydrolyzed colloid reaction (HCR) technique
MARTINI, MARCO;MEINARDI, FRANCESCO;
1996
Abstract
Three-dimensional (3-D) thermoluminescence (TL) spectra of Eu3-:YVO4, Eu3+:YV0.4P0.6O4 and Eu3+:Ce:YPO4 powders irradiated by X-rays were studied in the temperature range 30-350°C. The powders were reacted by a special hydrolyzed colloid reaction (HCR) technique at ∼ 80°C and were subsequently fired at 800°C. The glow curves possess two major peaks indicating different defect structures. The first TL peak was observed at ∼ 85°C and represents defects in the anion sublattice. It was increased by extended firing and colloidization processes and by substituting PO3-4 for the VO3-4 anion. The second TL peak was found at 135°C and is generated by impurity defects in the cation site of an yttrium orthovanadate-phosphate system. It was identified by the assistance of the Ce dopant. In Eu3+:Ce:YPO4 the predominance of one of above-mentioned defect structures can be changed by a suitable selection of HCR parameters, thus obtaining high emission intensities caused by two orders of magnitude lower X-ray radiation levels than those used for the orthovanadates.
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