New materials for glass–ceramic X-ray storage phosphors

The development of transparent glass ceramics as X-ray storage phosphors and their advantages over their crystalline counterparts are briefly reviewed. Measurements of conversion efficiency, stimulation efficiency, storage times, and optical transparency are reported for the particular case of europium-doped fluorobromozirconate glass, in which rubidium and lithium replace the usual sodium component fraction. Annealing at 280 °C converts the as-prepared glass into a glass–ceramic which contains Rb2BaBr4 and RbBa2Br5 nano- and micro-crystallites. Only the RbBa2Br5 structure shows significant photo-stimulated luminescence after X-irradiation, and the maximum storage phosphor efficiency is 8% of that for the standard commercial storage phosphor BaFBr:Eu.