Rare Earth Doped Y2O3:RE3+ (RE= Eu, Tm and Tb) Powder Phosphors Prepared by Microwave Heating Technique
A simple microwave heating system was designed for firing phosphor samples. An 800W magnetron operating at 2.45 GHz was used. The system is capable of reaching 1200oC in less than three minutes with the help of SiC succeptor. The synthesis technique prior to the microwave heating is described. The results indicate that the samples start to crystallize after 5 minutes. The X-Ray diffraction (XRD) data indicates that the sample is polycrystalline and acquires the host structure. The Photoluminescence (PL) and Photoluminescence Excitation (PLE) spectra for the powder phosphor prepared show similar results as those prepared using the conventional method. The Y2O3 powder samples doped with Eu show strong red emission at 630nm, the Tb doped samples show a strong green emission at 550nm and Tm doped samples shows blue emission at 460nm. The Scanning Electron microscope (SEM) picture taken show that the crystal size of the microwave irradiated samples was smaller in comparison to those prepared using the conventional method. This may be due to shorter heating time. These results indicate that the microwave heating technique is a reliable, fast and suitable technique to produce these powder phosphors. The characteristics of the phosphors are as good as those prepared using the conventional heating technique.
A.K. Arof and S.A. Hashim Ali
I. Ishak, A. Daud, "Rare Earth Doped Y2O3:RE3+ (RE= Eu, Tm and Tb) Powder Phosphors Prepared by Microwave Heating Technique", Materials Science Forum, Vol. 517, pp. 227-231, 2006