Preparation and properties of Sm2O3 doped Y3Al5O12 powders

YAG powders with different Sm concentrations were synthesized by nitrate-citrate sol-gel combustion method. Phase evolution, morphology and luminescent properties of the obtained materials were characterized by XRD, FESEM, photoluminescent excited by purple light, respectively. Powder X-ray diffraction showed that cubic YAG : Sm crystallites were directly obtained at 800 degrees C from amorphous materials. The crystallization stage was characterized by an exothermic peak of DSC curve at 910 degrees C. FESEM micrographs revealed that the resultant phosphors were agglomerated with an average particle size of about 300 nm. The photoluminescence spectra excited by 405 nm wavelength showed several obvious emission bands located in the 550 similar to 700 nm, corresponding to (4)G(5/2) -> H-6(5/2), (4)G(5/2) -> H-6(7/2), (4)G(5/2) -> H-6(9/2) transitions of Sm3+ ions, respectively. For luminescence property, the emission intensity of YAG : Sm powders varied with the Sm contents and reached the maximum at 3% (mole fraction) Sm.