Synthesis and luminescent properties of nano-scale Y2Si 2O7:Re3+ (Re=Eu, Tb) phosphors via sol-gel method

Abstract

By using metal nitrates as starting materials and citric acid as a complexing agent, Y2Si2O7:Re3+ (Re=Eu, Tb) phosphors were prepared by a sol-gel method. X-ray diffraction was employed to characterize the resulting samples. The results of XRD indicate that the α-Y2Si2O7 nanocrystal with size of 27 nm is obtained at 1000 °C and the doping ion content does not influence the structure. The excitation spectra in the UV and VUV ranges and the emission spectra of Re3+ doped samples were measured. The excitation spectra in the VUV range is due to absorption of host, that in the UV range is ascribed to absorption transitions from 4f to 5d state of the Tb3+ and the charge transfer in the Eu3+-O2- bond. The spectral energy distribution of the Tb3+ emission depends strongly on the Tb 3+ concentration. The dependence of photoluminescence intensity on Re3+ concentration is also discussed in detail. The fluorescent decay curves at room temperature were measured and analyzed. © 2008 Chinese Physical Society.