Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Mar 25;122:489-98. doi: 10.1016/j.saa.2013.10.106. Epub 2013 Nov 7.
Dosimetric properties of γ-irradiated ZnAl2O4:Ce(3+) (1-9 mol%) nanophosphors were studied and reported for the first time. The phosphor prepared by solution combustion route was well characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. PXRD patterns of calcined phosphor show pure cubic phase of ZnAl2O4:Ce(3+). Flake type morphology was observed from SEM studies. The particle size estimated by Scherrer's and Williamson Hall (W-H) plots and found to be in the range 11-17 nm. From photoluminescence (PL) studies two characteristic emission peaks at 363 and 480 nm were observed due to 5d-4f transitions of Ce(3+) ions. The thermoluminescence (TL) glow curves of ZnAl2O4:Ce(3+) (1-9 mol%) nanophosphor recorded two glow peaks 145 and 215 °C at a warming rate of 2.5 °C s(-1). The optimized TL intensity was observed for ∼5 mol% Ce(3+) concentration. The two TL glow peaks in the γ-irradiated (0.1-6 kGy) ZnAl2O4:Ce(3+) (5 mol%) nanophosphor indicates that two set of traps were activated within the temperature range 145 and 215 °C. The kinetic parameters (E,b,s) associated with the prominent glow peaks were estimated using Chen's glow peak shape method. The intensity of the TL glow peak (145 °C) increases linearly with increase of γ-dose upto 1 kGy above which it follows sub-linear behavior. Track interaction model (TIM) was used to explain the linearity/sub linearity/saturation behavior of TL intensity. The TL glow curves show simple glow peak structure, good reusability, low fading and wide range of linearity. Hence, the optimized ZnAl2O4:Ce(3+) (5 mol%) nanophosphor was quite useful for radiation dosimetry and display applications.
γ 辐照的 ZnAl2O4:Ce(3+)（1-9 mol%）纳米荧光粉的剂量学性能首次被研究并报道。通过溶液燃烧法制备的荧光粉通过粉末 X 射线衍射（PXRD）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）技术进行了很好的表征。煅烧后的荧光粉的 PXRD 图谱显示出纯立方相的 ZnAl2O4:Ce(3+)。SEM 研究观察到片状形态。通过 Scherrer 和 Williamson Hall（W-H）图谱估算的粒径范围在 11-17nm 之间。从光致发光（PL）研究中观察到两个特征发射峰，位于 363nm 和 480nm，归因于 Ce(3+)离子的 5d-4f 跃迁。ZnAl2O4:Ce(3+)（1-9 mol%）纳米荧光粉的热致发光（TL）发光曲线在升温速率为 2.5°C/s 时记录到两个发光峰，温度分别为 145°C 和 215°C。在优化的 TL 强度下观察到约 5 mol% Ce(3+)浓度。在 γ 辐照（0.1-6 kGy）的 ZnAl2O4:Ce(3+)（5 mol%）纳米荧光粉中观察到两个 TL 发光峰，表明在 145°C 和 215°C 的温度范围内激活了两组陷阱。使用 Chen 的发光峰形状法估计与主要发光峰相关的动力学参数（E，b，s）。TL 发光峰（145°C）的强度随 γ 剂量的增加而线性增加，在 1 kGy 以上时，它遵循亚线性行为。轨道相互作用模型（TIM）用于解释 TL 强度的线性/亚线性/饱和行为。TL 发光曲线显示出简单的发光峰结构、良好的可重复性、低衰减和宽线性范围。因此，优化后的 ZnAl2O4:Ce(3+)（5 mol%）纳米荧光粉非常适用于辐射剂量测定和显示应用。
