Preparation And Luminescent Properties Of SrZrO₃: Sm～(3+), Eu～(3+) And CeO₂: Sm～(3+) Luminescent Materials

SrZrO₃: Sm³⁺ phosphor powders were prepared by solid state reaction method. The excitation spectra of SrZrO₃: Sm³⁺ phosphor displayed a broad band centered at 246nm, which was assigned to the charge transfer (CT) band of O^2--Sm³⁺. The emission spectra of SrZrO₃ Sm³⁺ phosphor showed three characteristic emission peaks, which can be attributed to the ⁴G_5/2→⁶H_5/2,⁴G_5/2→⁶H_7/2, and ⁴G_5/2→⁶H_9/2 transitions of Sm³⁺. The concentration quenching of SrZrO₃: Sm³⁺ phosphor occurred at about 8mol%.SrZrO₃: Eu³⁺ phosphor powders were synthesized by solid state reaction method and sol-gel method. For the phosphor synthesized by solid state reaction method, X-ray powder diffraction (XRD) analysis confirmed the formation of pure SrZrO₃: Eu³⁺ in the doping concentration of 0-3mol%. The excitation spectra of SrZrO₃: Eu³⁺ phosphor displayed a broad band around 295nm, which is due to the charge transfer (CT) band of O^2--Eu³⁺. The charge transfer is the dominant excitation mechanism for the photoluminescence (PL) of SrZrO₃: Eu³⁺. For the phosphor powders prepared by sol-gel method, TG-DTA curves, XRD and PL showed that SrZrO₃: Eu³⁺ begins crystallizing at 700℃ and its luminescence intensity increases with increasing the sintering temperature.The phosphor powders of CeO₂ doped with Sm³⁺ were prepared by solid state reaction method. The powder samples were characterized by XRD and PL. XRD analysis showed the formation of pure solid solution Ce_1-xSm_xO₂when the Sm³⁺concentration is below 4mol%. The dependence of luminescence intensity on the Sm³⁺ concentration in CeO₂: Sm³⁺ was studied. The luminescence intensity increased with increasing Sm³⁺ concentration, up to about 1mol %, and then abruptly decreased indicating the concentration quenching.