Xu Bingyu, Li Mingxia, Pan Kai, Li Rong, Fan Naiying, Wang Guofeng
J Nanosci Nanotechnol. 2016 Apr;16(4):3522-6. doi: 10.1166/jnn.2016.11848.
SrWO4:Ln3+ (Ln = Eu, Ce, and Tb) nanocrystals were successfully synthesized by a hydrothermal method, and were characterized by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The results indicated that the crystalline size of nanocrystals decreases with increasing Eu3+ concentrations and increases with increasing annealing temperature, gradually. The photoluminescence properties of SrWO4:Ln3+ were investigated in detail. In the emission spectra of SrWO4:Eu3+, the luminescence was dominated by 5D0--> 7F2 transition, indicating that Eu3+ occupied a site lacking inversion symmetry. The concentration quenching effect hardly occurs. In the excitation spectra of SrWO4:Eu3+ nanocrystals monitored at 619 nm, the most intense peak is centered at 467 nm when the Eu3+ concentration was less than 10%, while the most intense peak is centered at 396 nm when the Eu3+ concentration was 15%. In the normalized emission spectra of SrWO4:Ce3+/Tb3+ nanocrystals excited at 254 nm, the intensity ratio of the sharp emission peaks from Tb3+ ions to the broad emission band from Ce3+ ions increased with increasing Tb3+ concentration.
通过水热法成功合成了 SrWO4:Ln3+（Ln = Eu、Ce 和 Tb）纳米晶体，并通过 X 射线衍射、透射电子显微镜和扫描电子显微镜对其进行了表征。结果表明，纳米晶体的晶体尺寸随着 Eu3+浓度的增加而减小，并随着退火温度的升高而逐渐增加。详细研究了 SrWO4:Ln3+的光致发光特性。在 SrWO4:Eu3+的发射光谱中，发光主要由 5D0→7F2 跃迁主导，这表明 Eu3+占据了一个缺乏反演对称性的位置。浓度猝灭效应几乎不发生。在 SrWO4:Eu3+纳米晶体在 619 nm 处监测的激发光谱中，当 Eu3+浓度小于 10%时，最强峰位于 467 nm 处，而当 Eu3+浓度为 15%时，最强峰位于 396 nm 处。在 254 nm 激发的 SrWO4:Ce3+/Tb3+纳米晶体的归一化发射光谱中，Tb3+离子的尖锐发射峰与 Ce3+离子的宽发射带的强度比随着 Tb3+浓度的增加而增加。
