金属氧化物纳米半导体材料的可控制备、微观结构及物理化学性能研究

发布时间：2018-04-20 15:05

本文选题：金属氧化物纳米材料 + 微观结构　；参考：《青岛大学》2017年硕士论文

【摘要】：作为重要的功能材料,金属氧化物纳米半导体材料具有独特的光、电、热以及力学性能,在太阳能电池、催化剂、传感器和磁存储器中有着广泛的应用前景。材料的宏观性能取决于其形貌和微观结构,因此有必要对金属氧化物纳米半导体的性能与形貌和微观结构进行关联。本论文主要对金属氧化物纳米半导体材料的可控制备、微观结构和物理化学性能进行了系统的研究。第一章首先对金属氧化物纳米半导体材料的制备方法、物理化学性能、应用领域等方面进行了综述。此外,对纳米半导体材料的光催化性能和湿敏性能的研究做了详细的介绍。第二章利用真空加热法还原氧化铁纳米刀片,成功地制备出含有氧空位、位错以及孔洞等缺陷的还原氧化铁纳米刀片。在相同实验条件下,还原后的氧化铁纳米刀片相比于氧化铁粉末和纳米刀片具有更高的光催化降解效率。缺陷的存在减少了氧化铁纳米刀片中电子-空穴对的复合,加速了有机物的分解,因此还原后的纳米刀片的光催化性能得到大幅提升。第三章通过水热法,成功地制备出不同形貌的二氧化锡纳米结构,主要有三种形貌:纳米颗粒、纳米棒状组成的三维结构和纳米十二面体组成的三维结构。不同形貌二氧化锡纳米结构的湿敏性能研究表明,三维多级结构二氧化锡纳米十二面体具有响应-恢复时间短、湿滞小、灵敏度高和稳定性好等优点。纳米十二面体独特的三维结构以及暴露出高活性的{101}晶面显著提升了其湿敏性能。第四章利用高分辨透射电子显微镜对氧化铁纳米线中两种周期的调制结构进行研究。纳米线中的调制结构是由氧空位有序引起的,其周期分别为(30(?)0)晶面间距的10倍和(11(?)0)晶面间距的6倍。两种调制结构的纳米线中铁原子数与氧原子数之比分别为0.7407和0.7273,与四氧化三铁的铁和氧原子数之比(0.7500)非常接近。电子能量损失谱的研究表明,由于氧气供应不足,铁原子数与氧原子数之比将趋近于四氧化三铁的铁、氧原子数之比,从而使氧化铁纳米线达到稳定结构。
[Abstract]:As important functional materials, metal oxide nano-semiconductor materials have unique optical, electrical, thermal and mechanical properties, and have a wide range of applications in solar cells, catalysts, sensors and magnetic memories. The macroscopic properties of the materials depend on their morphology and microstructure, so it is necessary to correlate the properties of metal oxide nano-semiconductors with their morphology and microstructure. In this paper, the controllable preparation, microstructure and physical and chemical properties of metal oxide nanocrystalline semiconductor materials are studied. In the first chapter, the preparation methods, physical and chemical properties and application fields of metal oxide nanocrystalline semiconductors are reviewed. In addition, the photocatalytic and hygroscopic properties of nanometer semiconductor materials are introduced in detail. In chapter 2, the reduction of iron oxide nanocrystalline blades containing oxygen vacancies, dislocations and voids was successfully prepared by using vacuum heating method to reduce iron oxide nanocrystalline inserts. Under the same experimental conditions, the photocatalytic degradation efficiency of the reduced iron oxide nano-blade is higher than that of the iron oxide powder and nano-blade. The defect reduces the combination of electron-hole pair and accelerates the decomposition of organic matter in the iron oxide nano-blade, so the photocatalytic performance of the reduced nano-blade is greatly improved. In chapter 3, tin dioxide nanostructures with different morphologies have been successfully prepared by hydrothermal method. There are three main morphologies: nanocrystalline particles, nanorods and nano-dodecahedrons. The study of humidity sensitivity of tin dioxide nanostructures with different morphologies shows that the three-dimensional multilevel tin dioxide nanododecahedrons have the advantages of short response-recovery time, low humidity lag, high sensitivity and good stability. The unique three-dimensional structure of the nano-dodecahedron and the exposure of highly active {101} crystal surface significantly improved its humidity sensitivity. In chapter 4, the modulation structures of two periods in iron oxide nanowires are studied by high resolution transmission electron microscope. The modulation structure of nanowires is caused by the order of oxygen vacancy. The periods of the modulation structure are 10 times and 6 times of the distance between the crystal plane and the crystal plane, respectively. The ratio of the number of iron atoms to the number of oxygen atoms in the two modulated nanowires is 0.7407 and 0.7273 respectively, which is very close to the ratio of iron atom to oxygen atom of iron trioxide (0.7500). The study of electron energy loss spectra shows that due to the shortage of oxygen supply, the ratio of the number of iron atoms to the number of oxygen atoms will be close to that of iron and oxygen atoms of iron trioxide, so that the structure of iron oxide nanowires will be stable.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN304;TB383.1

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