Luminescence characterization of Dy and Eu doped Na6 Mg(SO4 )4 phosphors.

Abstract

A series of single-phase phosphors based on Na6 Mg(SO4 )4 (Zeff =11.70) doped with Dy and Eu was prepared by the wet chemical method. The photoluminescence (PL) and thermoluminescence (TL) properties of Dy3+ - and Eu3+ -activated Na6 Mg(SO4 )4 phosphors were investigated. The characteristic emissions of Dy3+ and Eu3+ were observed in the Na6 Mg(SO4 )4 host. The TL glow curve of the Na6 Mg(SO4 )4 :Dy phosphor consisted of a prominent peak at 234°C and a very small hump at 158°C. The TL sensitivity of the Na6 Mg(SO4 )4 :Dy phosphor was found to be four times less than the commercialized CaSO4 :Dy phosphor. The TL dose-response of the Na6 Mg(SO4 )4 :Dy phosphor was studied from a dose range of 5-10kGy and the linear dose-response was observed up to 1kGy which is good for a microcrystalline phosphor. Trapping parameters for both the samples were calculated using the Initial Rise and Chen's peak shape methods.