Al掺杂四针状ZnO纳米结构的制备及其光致发光和场发射特性

采用热蒸发法成功制备了Al掺杂四针状ZnO纳米结构(T-AZO),利用扫描电子显微镜、X射线衍射仪、荧光光谱仪和场发射测试系统分别研究了不同Al摩尔分数对T-AZO纳米结构表面形貌、微结构、光致发光谱和场发射特性的影响。实验结果表明:T-AZO纳米结构呈现六角纤锌矿结构,Al掺杂对四针状ZnO纳米结构的形貌产生明显影响并且使紫外发射峰产生蓝移。实验中,当Al掺杂摩尔分数为3%时,场发射性能最好,其开启场强为1.33 V/μm,场增强因子为8 420。

Fabrication of Tetrapod-liked Al-doped ZnO Nanostructures and Their Photoluminescence and Field Emission Properties

High-quality tetrapod-shaped Al-doped ZnO (T-AZO) nanostructures were synthesized via thermal evaporation of mixed Zn and Al powders. The effects of Al dopant concentration on the morphology, microstructure, optical and field emission (FE) properties of T-AZO were investigated using scanning electronic microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL) spectra and FE measurement. It is found that the incorporation of Al increases the aspect ratio of the tetrapods, leads to blue-shift in the UV region, and significantly improves the FE performances. The results also show that tetrapod cathodes with 3% Al mole fraction have the best FE properties, with a turn-on field of 1.33 V/μm, and a field enhancement factor as high as 8 420. The superior FE properties are mainly attributed to the high aspect ratio of the legs in the unique tetrapod-liked structures, and more electrons being induced in the conduction band by Al dopand.