SrAl2O4 : Eu2+, Dy long afterglow phosphors prepared by chemical coprecipitation method
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．