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At low temperature, some long-lasting phosphors could not work well in practical applications. So it is necessary to investigate the temperature dependence of the phosphors. The Y_2O_2S∶Eu, Ti, Mg microcrystalline samples were prepared by solid state reaction method. Phosphors were sintered at 1150 ℃ for 20 min in air, putting in and taking out both at high temperature. The emission spectra and the afterglow spectra as well as the thermoluminescence curve were measured for Y_2O_2S∶Eu, Ti, Mg. Its temperature dependence of the afterglow spectra and decay curves were studied from 140 to 300 K and from 290 to 350 K respectively. When the temperature is lower than 230 K, namely the start temperature point in its thermoluminescence curve, the intensity of the afterglow emission is weak, due to the probability of releasing electrons from traps is very small. With temperature rising from 230 to 290 K, the intensity of the afterglow emission are gradually increased and the thermoluminescence curve is going up. The reason is that the probability of releasing electrons from traps is becoming bigger and bigger. With temperature rising from 290 to 350 K, the decay time of the afterglow becomes quicker and quicker. As from 290 to 350 K the thermoluminescence curve is going down, the temperature is higher than the thermoluminescence peak 278.5 K indicating that the traps are rather shallow, and the electrons would be released from traps more easily and quicker. The behavior of the temperature dependence of the long afterglow of Y_2O_2S∶Eu, Ti, Mg is closely related with its thermoluminescence curve, and it was analyzed and discussed with the long-lasting phosphorescence mechanisms.
At low temperature, some long-lasting phosphors could not work well in practical applications. So it is necessary to investigate the temperature dependence of the phosphors. The Y_2O_2S: Eu, Ti, Mg microcrystalline samples were prepared by solid state reaction method. Phosphors were sintered at 1150 ° C for 20 min in air, putting in and taking out both at high temperature. The emission spectra and the afterglow spectra as well as the thermoluminescence curves were measured for Y_2O_2S: Eu, Ti, Mg. Its temperature dependence of the afterglow spectra and decay curves were studied from 140 to 300 K and from 290 to 350 K respectively. When the temperature is lower than 230 K, for the start temperature point in its thermoluminescence curve, the intensity of the afterglow emission is weak, due to the probability of releasing electrons from traps is very small. With temperature rising from 230 to 290 K, the intensity of the afterglow emission are gradually increased and the thermoluminesc The reason is that probability of releasing electrons from traps is becoming bigger and bigger. With temperature rising from 290 to 350 K, the decay time of the afterglow becomes quicker and quicker. As from 290 to 350 K the thermoluminescence curve is going down, the temperature is higher than the thermoluminescence peak 278.5 K indicating that the traps are rather shallow, and the electrons would be released from traps more easily and quicker. The behavior of the temperature dependence of the long afterglow of Y 2 O 2 S: Eu, Ti, Mg is closely related with its thermoluminescence curve, and it was analyzed and discussed with the long-lasting phosphorescence mechanisms.