Precipitation synthesis and low temperature luminescence prosperities of Zn2SiO4 : Mn2+ green phosphor

Green phosphor Zn2SiO4: Mn2+ for PDP was synthesized by precipitation reaction. The sample was characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), vacuum ultraviolet (VUV) spectra, ultraviolet (UV) spectra and FT-IR spectrum. XRD pattern shows that the sample is pure phase of Zn2SiO4 and well-crystallized. SEM image reveals that the sample shows nearly spherical morphology and the particles sizes are between 1 mu m and 5 mu m. VUV and UV emission spectra at 20 K, 50 K and 100 K show that the low temperature luminescence intensifies of the peaks at 523 nm which correspond to the T-4(1) ((4)G)->(6)A(1) (S-6) transitions of Mn2+ ions become weak with the increasing of the measured temperature under 147 nm and 254 nm excitation. The excitation spectrum illustrates two strong absorption peaks at around 210 nm. and 243 nm, which are ascribed to the transitions of the charge transfer states when 523 nm emission is monitored. The absorption peaks of SiO2, v(j) SiO4 (j=1, 2, 3) and v(j) ZnO4 (j = 1, 3) could be observed in FT-IR spectrum.