稀土Y(下标 2-x)SiO5:Eu(下标 x)(上标 3+)纳米发光材料结构对发光性能影响及发光机理研究

Nano-meter Y(subscript 2-x)SiO5:Eu(subscript x) materials were synthesized by sol-gel method, and its structure and morphology were characterized by XRD, FTIR and TEM. The influence of phase structure, calcination temperature and Eu(superscript 3+) doping concentration on luminescence properties was investigated. The results show that the materials obtained at calcination temperature below 900℃ mainly present non-crystal state, while the materials mainly exhibit crystal state structure when calcined over 900℃. The particle size increased with the calcination temperature. The particle size was 15~45 nm and 60~80 nm for amorphous and crystal forms, respectively. The excitation and emission spectra of materials are all affected by phase structure, calcination temperature and Eu(superscript 3+) doping concentration. For Y(subscript 2-x)SiO5:Eu(subscript x) nanocrystal samples, in excitation spectra the charge transfer state (CTS) in crystal state absoption peak appeared red-shifted obviously compared with that in amorphous form, and in emission spectra the strong emission peak corresponding to 5D0→7F2 transition was observed and its intensity increased and decreased, respectively, with the calcination temperature for amorphous samples and crystal samples, at the same time two novel sharp emissions peaks were found at longer wavelength and became stronger with particle size. The spectra with respect to the 5D0→7F1 transition splitted into sharp triple peaks, but the emission spectra corresponding to 5D0→7F0 transition was almost not affected by the crystal phase and the particle size. While in the crystal Y(subscript 2-x)SiO5:Eu(subscript x) of 60~80 nm, the luminescence intensities of 5D0→7F2 and 5D0→7F1 transitions were influenced by Eu(superscript 3+) doping concentration, when the Eu(superscript 3+) doping concentration was at x=0.4, the luminescence intensity was the strongest.