Synthesis and characterization of nano-sized YAG:Ce, Sm spherical phosphors

YAG:Ce, Sm spherical phosphors were synthesized by malic acid sol-gel method. The formation process of crystalline was characterized by X-ray diffraction (XRD) technique. The influence of Sm3+ doping on the luminescent intensity and the morphology of phosphors were studied by fluorescence spectrum and scanning electron microscopy (SEM) techniques, respectively. The results indicated that the size of spherical powders was about 100 nm calcined at 1200 °C for 3 h. The emission spectra of phosphors showed gradual red-shift from 525 to 540 nm with the increase of doping concentration of Sm3+ ion. A broadband emission spectrum of Ce3+ ion appeared at 540 nm, and a series of emission peaks corresponding to the 4G5/2→6HJ transition of Sm3+ ion also appeared at 617 nm with the doping of Sm3+. The red component of YAG:Ce phosphors increased with the doping of Sm3+.