聚合物基ZnO纳米线的制备和生长机理研究

采用独特的高分子溶液自组装生长方法, 在经化学镀预处理的基底上利用高分子溶液的网络络合效应制备了ZnO纳米线. 通过场发射扫描电子显微镜(FE-SEM), X射线能谱仪(EDS)等对样品的表面形貌及组成进行了观测表征. 结果显示, 纳米线直径约50 nm, 长度达到了数微米; 产物Zn、O化学计量比接近1∶1. 通过Si基底经化学镀工艺预处理和未经化学镀预处理对ZnO纳米结构、紫外吸收和PL性能影响的分析比较, 发现了化学镀Ni对于纳米线长度和直径尺寸的控制更为有效; 在PL图谱中, 经化学镀预处理的样品在中心波长385 nm出现了由激子碰撞复合所形成的近紫外发光峰. 进一步还分析了在不同的pH值和反应时间下样品的紫外吸收和光致发光性能. 通过以上实验, 讨论并提出了ZnO纳米线的生长机理及过程, 认为纳米线的生长是在化学镀催化剂和高分子双重作用下进行的.

Preparation and Growth Mechanism of Polymer/ZnO Nanowires

By the unique method of polymer solution self-assembling and its complex effect, zinc oxide (ZnO) nanowires were fabricated on the Si substrate pretreated with a method of electroless plating. The sample composition and surface morphology were observed and characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray spectrometry (EDS). It was found that the size of diameter mostly was 50 nm, and the lengths reached several microns; the sample was basically composed of elements Zn and O, and the ratio of Zn/O was about 1∶1. By the comparison of different morphology, UV absorption and PL spectra of the samples with electroless plating and without electroless plating, it was found that the electroless plating was a more effective method for controlling the length and diameter size of the nanowires, and there was a strong near UV emission peak at about 385 nm, which results from the exciton composite and collision. Furthermore, the UV absorption and PL spectra of the samples were analyzed at different pH value and reaction time. The growth process and mechanism of the ZnO nanowires were discussed, and it was considered that the growth process was controlled by the effects of catalyzed active particles via electroless Ni plating and the complex function of the polymer network.