Yu Lixin, Song Hongwei, Liu Zhongxin, Yang Linmei, Lu Shaozhe
Key Laboratory of Excited State Physics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 16 Eastern Nan-Hu Road, Changchun 130033, P. R. China.
Phys Chem Chem Phys. 2006 Jan 14;8(2):303-8. doi: 10.1039/b512087j. Epub 2005 Nov 9.
One-dimensional La(2)O(3):Eu(3+) nanowires (NWs) and sub-micrometer samples (SMs) were fabricated by a hydrothermal method. Their photoluminescent characteristics were studied and compared. The results indicated that the exciton band in NWs blue-shifted in contrast to SMs. In comparison with the charge transfer (CT) band, the relative intensity of the exciton band in NWs was lower than that in SMs, which was attributed to the more energy transfer from the exciton band to surface defects. Frequency-selective-excitation spectra indicated that there existed three symmetry sites of Eu(3+) ions in NWs and two sites in SMs. The results of the temperature dependence of (5)D(1)-(7)F(2) lifetimes indicated that the electronic radiative rate of (5)D(1)-Sigma(7)F(J) in the two samples had hardly any variation and the nonradiative transition rate of (5)D(1)-(5)D(0) in NWs increased slightly.
采用水热法制备了一维La(2)O(3):Eu(3+)纳米线(NWs)和亚微米样品(SMs)。对它们的光致发光特性进行了研究和比较。结果表明,与SMs相比,NWs中的激子带发生了蓝移。与电荷转移(CT)带相比,NWs中激子带的相对强度低于SMs中的相对强度,这归因于激子带向表面缺陷的能量转移更多。频率选择性激发光谱表明,NWs中存在Eu(3+)离子的三个对称位点,SMs中存在两个位点。(5)D(1)-(7)F(2)寿命的温度依赖性结果表明,两个样品中(5)D(1)-Σ(7)F(J)的电子辐射率几乎没有变化,NWs中(5)D(1)-(5)D(0)的非辐射跃迁率略有增加。