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A D-π-D type of organic dye 2,7-di[4-(N,N-diphenylamino)styryl]-9-n-pentyl-9H- carbazole (DPSPC) with diphenylamine as donor group and styrene-carbazole-styrene as conjugation bridge has been synthesized. The photophysical properties of the dye in different solvents and poly methyl methacrylate/organic modified sol-gel glasses are researched. The results indicate that the fluorescence properties of the organic dye in composite glass increase relative to that in solvents and there are no fluorescence quenching in high doped concentration in composite glass matrixes. The dye has higher stability in the composite glass than that in solution.

Zn2SiO4 single-doped and co-doped with Mn2+ ions and Pb2+ ions has been prepared by a sol–gel process. The luminescent properties of the samples have been investigated. From the excitation and emission spectral analysis, it was found that the emission peaks vary with the change of the excitation wavelength. An enhanced luminescent characteristic of Mn2+ ions (in blue and green spectral zones) has been observed, due to the energy transfer from the Pb2+ ion to the Mn2+ ion. The emission peaks originate from the d–d transitions of the Mn2+ ion. However, the relative intensities of the peaks show a dependence on the concentration of the Pb2+ ion.

Cu-doped, Ce-doped and CuCe-doped SrAl 2 O 4 luminescent materials have been synthesized by solid state reaction at 1200 °C and weak oxidation atmosphere. The photoluminescence (PL) and excitation spectra of the doped samples have been investigated at room temperature. The excitation spectrum of Ce 4+ -doped SrAl 2 O 4 sample consists of two sharp bands, one in the ultraviolet (381 nm) and the other in the visible (517 nm) part of the spectrum. The PL spectra of Ce 4+ -doped SrAl 2 O 4 sample vary with the changing of the excitation wavelength. Because of the energy transfer between Cu 2+ and Ce 4+ , the PL and excitation spectra of the sample co-doped with Cu 2+ and Ce 4+ are dramatically different from that of Ce 4+ -doped sample. Also, the PL spectra of the co-doped sample change with using different excitation wavelength.

The changing presented during the heating of sol–gel derived Zn2SiO4 doped with Ni2+ have been investigated by X-ray diffraction (XRD) and differential thermal analysis (DTA). When calcining temperature 900 °C, XRD pattern of the sample shows the characteristic peaks of α-Zn2SiO4 crystal phase. Also, the excitation and emission spectra of the undoped and Ni2+-doped samples have been investigated. Stable green–yellow–red emission has been observed from Zn2SiO4 crystalline phase. A novel photoluminescence (PL) phenomenon has been observed from Ni2+-doped Zn2SiO4.