Abstract: | Phosphor yttrium aluminum garnet Y3Al5O12 (YAG), activated with trivalent cerium (Ce3+), was synthesized by T-tube impinging streams, T-type vortex impinging streams co-precipitation method (IS-CP) and direct
co-precipitation method (D-CP), respectively. The crystallization, morphologies, particle size and particle size distribution
of the phosphors obtained under different experimental conditions were studied. The influence of various factors on the luminescence
intensity of the phosphor was also investigated, such as feeding methods, volume flow rate, contents of Ce and initial reactant
concentration. The results show that the precursors synthesized by T-tube impinging streams co-precipitation reaction transform
to Y3Al5O12 (YAG) phosphor at about 1 000 °C. The particles are far smaller and narrower than those prepared by D-CP. In the impinging
streams co-precipitation system, the luminescent intensity of YAG:Ce phosphor increases with the increase of liquid flow rate.
The intensity firstly increases then decreases with the increasing Ce3+ doping content, and the maximum intensity is shown at 1.67% (molar fraction) Ce. Luminescent intensity gradually decreases
with the increase of initial concentration of reactants. At the same operational condition, the luminescent intensity of the
phosphors prepared by T-tube impinging streams reactor is higher than that by D-CP, and the luminescent intensity of the phosphors
prepared by T-type vortex impinging streams is higher than that by T-tube impinging streams reactor. |