writer：Sun, YB，Qiu, GM(*)，Zhang, SQ，Zhang, M，Yan, CH，Dai, SJ
keywords：luminescence；strontium aluminate；long afterglow phosphors；coprecipitation method；rare earths
source：期刊
specific source：Journal of Rare Earths
Issue time：2004年
SrAl₂O₄：Eu“，Dy”long afterglow phosphors were um carbonate and ammonium hydrogen carbonate were used as prepared by chemical coprecipitation method．Ammoni— the precipitants．The preparation of the SrAl2 04：Eu2+， Dy3+precursor was completed at room temperature by controlling the concentration of the metal—salt solution，pH value of the system．etc．The phosphors were prepared by sintering the precursor at 1000～1200℃in a weak reducing at— mosphere for 2 h．The XRD．SEM，excitation spectra，emission spectra and afterglow decay of the samples were tested and the optimal synthesis conditions of the SrAl2 04：Eu“，Dy”long afterglow phosphors prepared by precipitation method were determined．The phosphor which had good luminescent properties 1s prepared and lts persistent time can reach more than 1 600 min．In the coprecipitation process，a small amount of glucose operates to refe the luminescent powders．The particle size of the phosphor can be less than l ixm．The sintering temperature of the sample prepared by the coprecipitation method is much 10wer than that of the one prepared by the high temperature solid state method． Compared with the high temperature solid state method，a clear blue shift occurs in the excitation and emission spectra of the samples．