纳米金属氧化物光电材料的制备、微观结构及其物理化学性能研究

发布时间：2018-11-20 10:09

【摘要】：随着纳米科技的发展,纳米光电材料展现出比块材更加优异的物理化学性能。因此,纳米光电材料的研发工作引起了人们的广泛兴趣。近几年来研究发现,金属氧化物纳米光电材料由于其独特的物理化学性能和简便的制备工艺,使其在环境保护、纳米光电子器件以及太阳能电池中呈现出巨大的应用前景。本论文详细研究了氧化亚铜纳米颗粒、有机染料/二氧化钛及氧化铜/氧化亚铜纳米杂化材料等金属氧化物纳米半导体材料的微观结构及其光电性能,阐明了其生长机理,关联了材料微观结构与宏观物化性能。主要研究内容如下:(1)在不同温度下,通过调控电化学沉积过程的电流密度与反应时间,保持总电量不变,制备出不同形貌的Cu2O纳米晶。利用扫描电子显微镜和紫外分光光度计探讨了不同实验条件对沉积产物的形貌、尺寸及成分的影响,进一步深入地研究了Cu2O纳米晶电化学沉积的生长机制。(2)利用无电极沉积法制备出形貌规则的Cu2O纳米八面体颗粒,并通过扫描电子显微镜和透射电子显微镜对不同金属基底上得到产物的微观结构进行了细致的研究,并提出了其生长机理模型。此外,探究了Cu2O纳米八面体的光学性能及其光催化活性。(3)利用自组装技术制备出有机染料与TiO2纳米颗粒杂化的有机/无机杂化纳米材料。利用扫描电子显微镜和透射电子显微镜对其微观结构进行了细致的观察研究,发现有机分子优先吸附于TiO2纳米颗粒的{101}面,并与其光学性能进行关联。利用密度泛函理论深入地探究了有机染料分子在TiO2纳米颗粒{101}表面的择优吸附。(4)Cu2O/CuO纳米杂化材料微观结构的前期研究工作发现,生长在CuO纳米线上的Cu2O纳米颗粒存在纳米立方体和纳米八面体两种结构,其中八面体形貌所占比例约为80%。本论文利用紫外-可见吸收光谱检测Cu2O/CuO纳米杂化材料光催化降解甲基橙的活性,发现其光催化活性有了显著的提升,并利用密度泛函理论探究了Cu2O/CuO纳米杂化材料的光催化活性改善的机理。
[Abstract]:With the development of nanotechnology, nano-optoelectronic materials exhibit better physical and chemical properties than bulk materials. Therefore, the research and development of nano-optoelectronic materials has aroused wide interest. In recent years, it has been found that metal oxide nano-optoelectronic materials have great application prospects in environmental protection, nano-optoelectronic devices and solar cells due to their unique physical and chemical properties and simple preparation process. In this paper, the microstructure and photoelectric properties of metal oxide nanocrystalline semiconductors, such as cuprous oxide nanoparticles, organic dyes / titanium dioxide and copper oxide / cuprous oxide nanohybrid materials, were studied in detail, and the growth mechanism was explained. The microstructure of the material is correlated with the physical and chemical properties of the material. The main contents are as follows: (1) Cu2O nanocrystals with different morphologies were prepared by adjusting the current density and reaction time of electrochemical deposition at different temperatures and keeping the total electric quantity unchanged. The effects of different experimental conditions on the morphology, size and composition of the deposited products were investigated by means of scanning electron microscope (SEM) and ultraviolet spectrophotometer. The growth mechanism of electrochemical deposition of Cu2O nanocrystals was further studied. (2) Cu2O nano-octahedron particles with regular morphology were prepared by electrodeless deposition. The microstructure of the products on different metal substrates was studied by scanning electron microscope (SEM) and transmission electron microscope (TEM), and the growth mechanism model was proposed. In addition, the optical properties and photocatalytic activity of Cu2O nanooctahedron were investigated. (3) Organic dyes and TiO2 nano-particles hybrid organic / inorganic hybrid nanomaterials were prepared by self-assembly technique. The microstructure of TiO2 nanoparticles was investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). It was found that the organic molecules were preferentially adsorbed on the {101} surface of TiO2 nanoparticles and correlated with their optical properties. The preferential adsorption of organic dye molecules on the surface of TiO2 nanoparticles {101} was investigated by using density functional theory. (4) the previous studies on the microstructure of Cu2O/CuO nano-hybrid materials were carried out. The Cu2O nanoparticles grown on CuO nanowires have two kinds of structures: nano-cube and nano-octahedron, in which the octahedral morphology is about 80%. In this paper, the photocatalytic activity of Cu2O/CuO nano-hybrid materials for degradation of methyl orange was detected by UV-Vis absorption spectra, and it was found that the photocatalytic activity of Cu2O/CuO nano-hybrid materials was significantly improved. The mechanism of the improvement of photocatalytic activity of Cu2O/CuO nano-hybrid materials was investigated by density functional theory (DFT).
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TB383.1

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