氧化物复合纳米结构的控制合成及其性能研究

发布时间：2018-11-06 12:11

【摘要】：本文首先利用化学气相沉积法合成出花状ZnO与带状SnO_2纳米结构。然后以合成的带状SnO_2纳米结构为基础,结合溶液法研究了氧化物复合纳米结构的控制合成。还以花状ZnO为原料制成柔性紫外探测器,并研究了SnO_2复合ZnO之后的光催化性能和光电化学性能。第一章从纳米科技,纳米材料在紫外探测器件的运用,以及纳米材料在半导体光催化应用三块分别介绍。纳米科技概述了其定义,引出纳米材料的物理特性,以及纳米材料的合成方式。纳米材料在紫外光探测器件的应用主要介绍了紫外光探测技术在其应用方向的重要意义,紫外光探测器件的种类和发展方向,最后论述了纳米材料的性质应用在制备高性能紫外光探测器件拥有巨大优势。纳米材料在半导体光催化应用,介绍了半导体光催化技术的净化环境方面的突出表现,概述了光催化的原理,分析了影响光催化性能的因素。第二章研究了花状Zn O纳米结构的合成,并以其为光电探测材料制备出柔性紫外探测器件,分析了器件的光电性能。具体来说:首先用化学气相沉积法,以锌粉和纯氧气为原料制备出花状ZnO纳米材料,使用扫描电镜、X射线衍射对其表征和研究。之后我们用非常简易的“刻划法”,在镀金的柔性PET基底上制作柔性紫外探测器件进行试验。研究结果表明,该器件在试验中弯曲了不同角度后所展示出的灵敏度依然很高,而且都能够在电压为6v的条件开关紫外灯时迅速做出反应且光电流与暗电流比值高达105。第三章研究了SnO_2纳米带及其复合纳米结构的控制合成。首先,用化学气相沉积法(CVD)合成带状SnO_2,并通过SEM、XRD测试手段对其表征。接下来,基于带状SnO_2纳米材料进行复合研究,分别用乙酸锌水溶液、乙酸锌乙醇溶液合成了SnO_2/ZnO复合纳米结构,并SEM、EDS、XRD、TEM测试手段对其进行表征。对比分析发现,SnO_2在乙酸锌乙醇溶液浸泡比在乙酸锌水溶液浸泡最终得到的SnO_2/ZnO形貌长得更均一,复合效果更好。第四章研究了SnO_2/ZnO复合纳米结构的光电化学及光催化性质。我们使用三电极法测试样品光电化学响应,将样品涂在ITO表面形成薄膜制作为工作电极。使用氙灯平行光源来模拟太阳光,我们用电化学分析仪测试出样品间歇光照i-t曲线,并对比SnO_2/ZnO与SnO_2的间歇光照i-t曲线。实验结果证明,SnO_2与Zn O复合以后大大提升了光电转化效率,光电流增大明显,光响应十分灵敏,弛豫时间极短,达到了提高光电化学性能的目的。之后,以SnO_2/ZnO为原料制固定型光催化剂,测试出两次SnO_2/ZnO复合材料光催化降解性能,并与纯的SnO_2进行对比。实验结果证明,SnO_2/ZnO复合纳米材料的光催化降解能力高于纯SnO_2的光催化能力,SnO_2/ZnO固定型光催化剂二次使用仍然有较好降解能力。
[Abstract]:Firstly, flower-like ZnO and banded SnO_2 nanostructures were synthesized by chemical vapor deposition. Then the controlled synthesis of oxide composite nanostructures was studied by solution method based on the SnO_2 nanostructures. Flexible UV detectors were prepared from flower-like ZnO and the photocatalytic and photochemical properties of SnO_2 composite ZnO were studied. The first chapter introduces the nanotechnology, the application of nano-materials in UV detectors, and the application of nano-materials in semiconductor photocatalysis. The definition of nanotechnology, the physical properties of nanomaterials and the synthesis of nanomaterials are summarized. The application of nanomaterials in ultraviolet detectors is introduced in this paper. The significance of ultraviolet detection technology in its application direction, the types and development direction of ultraviolet detectors are introduced. Finally, the properties and applications of nanomaterials in the preparation of high performance UV detectors have great advantages. The application of nanomaterials in semiconductor photocatalysis is reviewed. The outstanding performance of semiconductor photocatalytic technology in purifying environment is introduced, the principle of photocatalysis is summarized, and the factors affecting photocatalytic performance are analyzed. In chapter 2, the synthesis of flower-like Zn O nanostructures is studied, and the flexible ultraviolet detectors are prepared by using them as photodetector materials. The photoelectric properties of the devices are analyzed. Specifically, the flower-like ZnO nanomaterials were prepared by chemical vapor deposition with zinc powder and pure oxygen as raw materials. They were characterized and studied by scanning electron microscope (SEM) and X-ray diffraction (XRD). After that, we fabricated flexible UV detectors on a gold-plated flexible PET substrate by a very simple "scribing method". The results show that the sensitivity of the device is still very high after bending different angles in the experiment, and it can react quickly when the voltage is 6 v, and the ratio of photocurrent to dark current is as high as 105. In chapter 3, the controlled synthesis of SnO_2 nanobelts and their composite nanostructures are studied. Firstly, (CVD) was synthesized by chemical vapor deposition and characterized by SEM,XRD. Then, based on the ribbon SnO_2 nanocomposites, SnO_2/ZnO nanostructures were synthesized by zinc acetate aqueous solution and zinc acetate ethanol solution, respectively, and characterized by SEM,EDS,XRD,TEM. It was found that the morphology of SnO_2 in zinc acetate ethanol solution was more uniform than that in zinc acetate solution, and the composite effect was better than that in zinc acetate solution. In chapter 4, the photochemical and photocatalytic properties of SnO_2/ZnO nanostructures are studied. Three electrode method was used to measure the photochemical response of the sample. The sample was coated on the surface of ITO to form a thin film to be a working electrode. The parallel light source of xenon lamp was used to simulate solar light. We measured the I-t curves of samples by electrochemical analyzer, and compared the I-t curves of SnO_2/ZnO and SnO_2. The experimental results show that the photoconversion efficiency of SnO_2 and Zn O is greatly improved, the photocurrent increases obviously, the photoresponse is very sensitive, and the relaxation time is very short. After that, the photocatalytic degradation of SnO_2/ZnO composite was determined by using SnO_2/ZnO as raw material and the photocatalytic degradation was compared with that of pure SnO_2. The experimental results show that the photocatalytic degradation ability of SnO_2/ZnO nanocomposite is higher than that of pure SnO_2, and the secondary use of SnO_2/ZnO fixed photocatalyst still has good degradation ability.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.1

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