A. Katelnikovas

CHARACTERIZATION OF CERIUM-DOPED YTTRIUM ALUMINIUM GARNET NANOPOWDERS SYNTHESIZED VIA SOL-GEL PROCESS

In this work the sol-gel process was used to prepare Ce-doped yttrium aluminium garnet (Y 3 A l 5 O 12, YAG) samples. The synthesis products were characterized by infrared spectroscopy (IR), X-ray powder diffraction analysis (XRD), and transmission electron microscopy (TEM). The particle size and luminescence properties of synthesized samples were also determined. The XRD patterns of Y 3 A l 5 O 12:Ce samples showed that phase purity of garnets depends on the synthesis temperature and concentration of dopant. The YAG:Ce samples calcined at 1000°C showed the formation of single-phase YAG in the whole doping range (from 0 up to 10 mol% of Ce). However, during calcination at 1300°C the formation of CeO2 as an impurity phase at >4 mol% of Ce was observed. The mean particle size of Y 3 A l 5 O 12:Ce sample (4 mol% of Ce) synthesized at 1300°C was determined to be approximately 180–280 nm. The luminescence properties of Ce-doped YAG also depend on cerium concentration in the samples. The highest emission (λ ex = 450nm) intensity was determined for Y 3 A l 5 O 12:Ce samples doped by 5–6 mol% of Ce.