Europium doped MBrCl （M=Ca, Sr, and Ba） phosphors were prepared by solid state reaction in reductive atmosphere. Photolu- minescence （PL）, photostimulated luminescence （PSL） after X-ray irradiation and optical absorption studies of MBrCI：Eu2＋ （M=Ca, Sr, and Ba） revealed that： （1） blue light emission, under the excitation of 300 nm, was observed in all these phosphors; （2） the shape of the emission spectra in CaBrCI：Eu2＋ could be changed by varying the bromine/chlorine ratio during synthesis, while that in SrBrCI：Eu2＋ and BaBrCI：Eu2＋ showed no change; and （3） PSL was observed in SrBrCI：Eu2＋ and BaBrCI：Eu2＋ after X-ray irradiation. Difference absorption spectrum （DAS） in SrBrCl：Eu2＋showed two broad bands centered at about 470 and 570 nm, and DAS in BaBrCl：Eu2＋showed two bands at about 550 and 675 nm, respectively. This enabled the use of He-Ne laser （633 nm） or even semiconductor fight-emitting diodes （LED） instead of gas lasers for photostimulation.
A series of Eu2＋-doped fluorochlorozirconate glass-ceramics were prepared by solid state reaction method. X-ray diffraction, pho- toluminescence, photo-stimulated luminescence （PSL） and the turbidity of fluorozirconate glass containing BaCl2 nano- and micro-crystals were measured for the samples annealed at 290℃ for 10 rain The PSL was attributed to the characteristic emission of Eu2＋ in nano-crystallites of BaCI2, which formed in the glass upon annealing. The PSL efficiency of the glass ceramic was increased by increasing the concentration of BaCl2, which, however, resulted in the decreasing in the transparency of the sample. The sample turned to a semi-transparent glass ceramic or even an opaque and milky white one from a near-transparent glass. The trade-off between optical transparency and PSL intensity over different concentrations of BaCl2 for X-ray imaging plate applications was briefly discussed.
