Strong and unusual violet-blue emission in ring shaped ZnO nanocrystals
Strong and unusual violet-blue emission in ring shaped ZnO nanocrystals
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DOI：
10.1039/c1jm13083h
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发表时间：
2011-11
影响因子：
--
通讯作者：
O. Mondal;M. Pal
中科院分区：
文献类型：
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作者：
O. Mondal;M. Pal
采用十六烷基三甲基溴化铵（CTAB）为介质的软化学方法，在无模板条件下生长出了分散性较好的ZnO纳米环。合成的材料已经通过X射线衍射（XRD）、紫外-可见（UV-Vis）吸收研究、傅里叶变换红外分析（FTIR）、高分辨率透射电子显微镜（HRTEM）和光致发光（PL）研究进行了广泛的表征。XRD和HRTEM均表明超细ZnO纳米粒子聚结成纳米环，纳米环本质上是晶体，沿沿着（101）方向取向。所观察到的紫外-可见光谱显示这些纳米环的蓝移。室温下的光致发光测量表明，紫蓝色的发射有关的结构缺陷，这是几乎无法观察到的。发现了一些新的发射特征，并根据实验结果提出了一个带模型，简要讨论了解释这种现象的可能机制。
ZnO nanorings, relatively well dispersed, have been grown without any template by adopting a soft chemical route mediated by cetyltrimethylammonium bromide (CTAB). As-synthesized materials have been extensively characterized by X-ray diffraction (XRD), UV-visible (UV-Vis) absorbance studies, Fourier transform infrared analysis (FTIR), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) studies. Both XRD and HRTEM indicate that ultrafine ZnO nanoparticles coalescence into the nano-rings which are crystalline in nature and oriented along the (101) direction. The observed UV-Vis spectra show a blue shift for these nano-rings. Room temperature photoluminescence measurements show violet blue emission related to the structural defects, which can barely be observed. Some new emission features are uncovered and a possible mechanism to explain it is briefly discussed with the help of a band model proposed on the basis of experimental results.