WAN You-bao, CHU Jun-hao, HUANG Fang-peng. Second Harmonic Generation of Nonlinear Optic Crystal Potassium Lithium Niobate[J]. Chinese Journal of Luminescence, 2000,21(2): 129-132
WAN You-bao, CHU Jun-hao, HUANG Fang-peng. Second Harmonic Generation of Nonlinear Optic Crystal Potassium Lithium Niobate[J]. Chinese Journal of Luminescence, 2000,21(2): 129-132DOI:
Green-emitting phosphors of yttrium borophoshate coactivated with Ce
3+
、Tb
3+
and Gd
3+
have been prepared for the first time by a single step of firing
using BPO4 and rare earth oxides as reactants.With the aid of emission spectra and excitation spectra
the spectroscopic properties of Ce
3+
、Tb
3+
and Gd
3+
and interaction among them in yttrium borophosphate have been studied.In the systems doped with Tb
3+
Ce
3+
or Gd
3+
the energy transfers from Ce
3+
to Tb
3+
or from Gd
3+
to Tb
3+
are observed
but in the system activated with Ce
3+
and Gd
3+
the competitive absorption and individual emission between them are found.After the incorporation of gadolinium into the yttrium borophosphate doped with Ce
3+
and Tb
3+
the increment of Ce
3+
emission intensity is more than that of Tb
3+
emission intensity. It is considered that the increment of Ce
3+
emission intensity is due to prevention of energy transfer from Ce
3+
to Tb
3+
and that of Tb
3+
emission intensity may attribute to effective energy transfer form Gd
3+
to Tb
3+
.In above system
Gd
3+
prevention of energy transfer from Ce
3+
to Tb
3+
may exists
which makes it impossible that Gd
3+
ion absorbs energy from Ce
3+
ion and transfer the energy to Tb
3+
ion
because 5d energy level of Ce
3+
ion is lower than 6I and 6P energy levles of Gd
3+
ion. If yttrium is replaced wholly by gadolinium in the matrix
the relative brightness of the prepared phosphor increases
however
x value of chromatic cordinates decreases slightly
so controlling the amount of gadolinium in the matrix will be of advantage to improving the luminescent characteristics of phosphors.