【作者】 朱卫兵；

【导师】 宗俊；

【作者基本信息】 华东师范大学 ， 分析化学， 2008， 硕士

【摘要】 纳米技术是当今世界尖端技术之一,纳米材料科学是集凝聚态物理学、胶体化学、配位化学、化学反应动力学、表面和界面化学等学科为一体的交叉科学。由于其所具有的特殊结构使得纳米材料具有了许多普通材料不具有的特殊性质,纳米材料在诸多领域有着广泛的应用前景。纳米氧化锌作为一种功能材料与普通氧化锌相比,由于纳米材料所特有的表面效应、小尺寸效应、量子效应和宏观量子隧道效应等,使得纳米氧化锌在光、电、磁、化学、生物学等方面具有一系列新的特殊性能。当前,关于纳米氧化锌的研究已经进行的非常多,并且在很多方面也取得了很大的进展。目前已经成功研究出很多纳米氧化锌的制备方法,关于纳米氧化锌的应用也开展了其在光催化领域、气敏性、涂料行业和作为发光材料等诸多方面的研究并且取得了很大的成功。本实验在这些研究的基础上对纳米氧化锌的制备和光催化性能进行了深入的研究,主要的研究内容和成果如下:1.纳米氧化锌的制备(1)、对目前应用广泛的直接沉淀法进行了改进,把超声波引入该方法中,并且选用合适的表面活性剂,制备出了分布均匀颗粒尺寸约为15nm的氧化锌颗粒。通过这种方法大大改善了直接沉淀法所具有的粒子粒径范围分布较宽且团聚现象较严重等缺点。(2)、本实验还对用水热分解法制备特殊形貌的纳米氧化锌进行了一定的研究。通过研究发现,锌粉在碱性环境中水热分解产生氧化锌的实验中加入硝酸锌、硝酸锰等溶液可以极大的改善产物的形貌和尺寸,通过这种方法制备出了花簇形氧化锌纳米棒。同时通过实验发现碱度对产物的形貌尺寸有很大的影响,碱度越高,制得的产物氧化锌纳米棒尺寸越小形貌越规则。该实验方法操作简单,很容易制得形貌良好的产物氧化锌纳米棒。2.纳米氧化锌的改性纳米氧化锌的应用在很多领域中都是将其混合在有机物中,而氧化锌作为无机物要直接添加到有机物中存在着相当大的困难,因此必须对其进行改性研究。本实验在运用直接沉淀法制得纳米氧化锌颗粒的基础上对其进行了改性研究,选择油酸作为改性剂,通过测定改性前后氧化锌的亲油化度对改性效果进行探讨,通过多种方法证明这种改性实际上是纳米氧化锌表面的羟基与油酸通过酯化反应从而把油酸接枝到纳米氧化锌颗粒上形成了单分子层,这样大大提高了纳米氧化锌的亲油性,使它能够更好的分散在有机溶剂中,同时还能有效的阻挡纳米氧化锌的团聚现象发生。3.纳米氧化锌的光催化性能研究ZnO是一种具有许多卓越性能的新型宽禁带Ⅱ—Ⅵ族化合物半导体材料,而目前利用半导体材料做催化剂,光催化氧化处理有机污染物已经成为研究的热点。本实验在前文研究纳米氧化锌制备方法的基础上,结合最近几年纳米氧化锌在光催化领域的应用情况,用制备的纳米氧化锌产物对亚甲基蓝、品红等有机染料进行光催化实验,对纳米氧化锌的光催化性能以及影响其光催化性能的几个因素进行综合性的研究。结果表面纳米氧化锌对于很多的有机物都有良好的光催化降解作用,并得出最佳的反应条件。更多还原

【Abstract】 Nanotechnology is the world’s cutting-edge technology, nano-materials science is set condensed matter physics, colloidal chemistry, coordination chemistry, chemical reaction dynamics, chemical and other surfaces and interfaces for the integration of cross-disciplinary science. Because of the special structure which makes nano-materials with many special nature that common materials do not have have a wide application. Nano-Zinc Oxide as a functional materials compared with ordinary zinc oxide, nano-materials because of the unique surface effect, small size effect, the quantum effect and the macro quantum tunnel effect, making nano-Zinc Oxide in the light, electricity, magnetic, chemical, Biology has a new series of special performance.At present, research on nano-zinc oxide has conducted many, and in many ways has also made great progress. We have successfully developed a lot of the preparation method of nano-Zinc Oxide, nano-zinc oxide on the applications for its photocatalytic fields, gas sensing, and the paint industry as a luminous materials, and so on and achieved great success. In this experiment on the basis of these studies for the preparation of nano-Zinc Oxide and photocatalytic properties of an in-depth study, the main research and results are as follows:1. The preparation of nano ZnOWe have done research on nano-Zinc Oxide by two different methods of preparation. At present the simple application of a wide range of direct precipitation has improved, the introduction of the ultrasound method, and selected the right surfactant, a uniform distribution of particle sizes of about 15 nm zinc oxide particles. Through these improvements has greatly improved by a direct precipitation of the particle size distribution of a wide scope of the phenomenon and reunion, and other more serious shortcomings.Apart from direct precipitation, this study also thermal decomposition of water prepared by special morphology of nano-zinc oxide to a certain amount of research. Through the study found that zinc powder in alkaline water environment in the thermal decomposition of zinc oxide produced in the experiment by adding zinc nitrate, manganese, such as nitric acid solution can greatly improve the shape and size of the product, this way of a flower-shaped clusters Zinc oxide nano-rods. At the same time, found that the alkalinity of the morphology of the impact of significant size, the higher alkalinity, the product of a system of zinc oxide nanorods morphology of the smaller size of the rules. The experimental method is simple, easy system in good shape the product of zinc oxide nanorods.2. The surface modification of nano ZnOThe application of nano-zinc oxide in many areas are mixed in their organic matter, and zinc oxide as a non - of direct-to add to organic matter, there are considerable difficulties, it is necessary to modify their research. This experiment in the use of direct precipitation method in nano-zinc oxide particles on the basis of a modified its research, choose oleic acid as a modifier, through the modification of zinc oxide before and after the oil-degree effect of the modification, Through a variety of ways that this modification is in fact the surface of the nano-zinc oxide and hydroxy acid etherification through to the oleic acid grafted nano-zinc oxide particles formed a single-molecule level, this has greatly enhanced the nano-zinc oxide The pro-oil to enable it to better spread in organic solvents, while effective in blocking the reunion phenomenon in nano-zinc oxide.3. The study on the catalytic capability of nano ZnOZnO is a kind of superior performance in many of the new wide band gap II-VI family compound semiconductor materials and semiconductor materials currently used as catalyst, photocatalytic oxidation of organic pollutants has been a hot research. The text of the first experimental study of methods of nano-zinc oxide on the basis of recent years, nano-zinc oxide catalyst in the field of optical applications, the use of nano-zinc oxide product of methylene blue, magenta, and other organic fuel photocatalytic Experiments on the photocatalytic properties of nano-zinc oxide and the impact of its photocatalytic properties of several factors undertake a comprehensive study. The results of the surface of nano-zinc oxide for many organic compounds have good photocatalytic degradation, and that the best conditions.更多还原