CHARACTERIZATION OF CERIUM-DOPED YTTRIUM ALUMINIUM GARNET NANOPOWDERS SYNTHESIZED VIA SOL-GEL PROCESS
Abstract
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 CeO 2 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 = 450 nm ) intensity was determined for Y 3 A l 5 O 12 : Ce samples doped by 5-6 mol% of Ce.