Lower temperature synthesis of cerium-doped polycrystalline lutetium pyrosilicate powders by a novel sol-gel processing

A novel sol-gel processing was developed to synthesize polycrystalline cerium-doped lutetium pyrosilicate (Lu2Si2O7:Ce, LPS:Ce) powders under low temperature. It was found that the addition of propylene oxide (PPO) could promote the formation of Lu-O-Si bonds in precursor, which was beneficial to the formation of LPS phase. X-ray diffraction (XRD) patterns indicated that the single-phased LPS powder was well crystallized at 1050°C. Microstructure observation demonstrated that the synthetic LPS powder was composed of ellipsoidal grains with the mean size of 40 nm. The luminescent properties were characterized by photoluminescence (PL), X-ray excited luminescence (XEL) and vacuum ultraviolet (VUV) spectroscopy at room temperature. The synthetic LPS:Ce powder emitted a broad emission spectrum centered at about 380 nm, which should be ascribed to the 5d→4f transition of Ce3+. Decay time of the synthetic LPS:Ce powder was measured to be only 32 ns.