CuS和PbTe基掺杂分级结构制备及机理研究

发布时间：2018-07-11 13:28

本文选题：水热/溶剂热 + 硫属化合物　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：硫属化合物及其固溶体合金纳米材料具有独特的晶格结构和物理化学行为,是研究最早最为成熟的一种功能材料,同时也是目前实际应用中最为广泛的材料之一。硫属化合物纳米材料主要可以分类为IV-VI族和II-VI族两类。新兴的硫属纳米材料以及硫属基纳米复合材料由于本身具备的特异的光电,力学、磁学和催化等性能,所以为目前发展高性价比,高效和环境友好的先进能源转换和存储设备(ECS)提供了重大机遇。人们希望可以着眼于纳米尺度,对材料的物理化学性质和结构相关度方面进行系统的研究,同时希望可以通过相关手段控制纳米结构来实现材料的定制属性。由于纳米材料的属性与其形貌尺寸存在极大相关性,制备尺寸分布均匀合理和形状规整的纳米晶是获得性能优异材料的必备条件。同时,要实现对其形貌的有效调控,这就需要对不同制备方法涉及的生长热力学、动力学和机理有一个深入清晰的认识。本论文以硫属Cu S和Pb Te基掺杂纳米晶体系为研究对象,选取研究者涉足不多的几类材料作为掺杂剂,采用水热/溶剂热法制备具有特殊微纳米结构的纳米晶聚集体材料。通过掺杂剂调控形貌,发掘掺杂剂与纳米晶聚集体驱动力之间的关系,为进一步探究纳米晶聚集体可控制备提供理论基础。实验合成了不同Cu S(M=Pb,Sb,Bi,La)花球聚集体和Pb Te(M=Ag,Sb)(Ag PbmSb Tem+2)多晶实心微米球,系统地考察了各项反应参数和反应时间对最终产物的影响。研究了Cu S基花球和Pb Te基微晶球的可控合成,提出了重要实验参数在分子水平上对体系中化学反应和纳米尺度上纳米晶生长聚集过程的影响,进而总结出相关反应机制和生长机理。Ag PbmSb Tem+2多晶实心微米球相比单掺三元体系和纯Pb Te二元体系,Ag PbmSb Tem+2多晶实心微米球作为锂离子电池负极材料的测试结果展现了其优异的电化学性能和高循环稳定性。本课题不仅对Pb Te基和Cu S基材料的液相合成进行了探究,其研究结果也能为硫属纳米晶掺杂体系的可控制备和性能研究提供一定意义上的借鉴和指导。
[Abstract]:Sulfur compounds and their solid solution alloy nanomaterials have unique lattice structure and physicochemical behavior. They are the earliest and most mature functional materials, and they are also one of the most widely used materials in practice. The nanometer materials of sulfur compounds can be classified into two groups: IV-VI and II-VI. The emerging sulfur nanomaterials and sulfur based nanocomposites, due to their unique optoelectronic, mechanical, magnetic and catalytic properties, make it possible to develop high performance-to-price ratios at present. Efficient and environmentally friendly advanced energy conversion and storage devices (ECS) offer significant opportunities. It is hoped that the physical and chemical properties and structural correlation of materials can be systematically studied by focusing on nanometer scale, and that the customized properties of materials can be realized by controlling nanostructures by relevant means. Because the properties of nanomaterials are closely related to their morphology and size, the preparation of nanocrystalline with uniform and reasonable size distribution and regular shape is an essential condition for obtaining excellent materials. At the same time, in order to control the morphology effectively, it is necessary to have a clear understanding of the growth thermodynamics, kinetics and mechanism involved in different preparation methods. In this paper, the Cu S and Pb Te based doped nanocrystalline systems are studied, and several kinds of materials with less involvement are selected as dopants. Nanocrystalline aggregates with special microstructures are prepared by hydrothermal / solvothermal method. The relationship between the dopant and the driving force of nanocrystalline aggregates is explored by adjusting the morphology of the dopants, which provides a theoretical basis for further exploring the controllable preparation of nanocrystalline aggregates. The aggregates of different CuS (MbPbSbSbSbSbSbSbTiLa) and PbTe (Mg-AgSb) (Ag PbmSb-Tem 2) solid microspheres were synthesized experimentally. The effects of reaction parameters and reaction time on the final product were systematically investigated. The controllable synthesis of Cu S based flower spheres and Pb Te based microcrystalline spheres was studied. The effects of important experimental parameters on the chemical reaction and nanocrystalline growth and aggregation at the molecular level in the system were proposed. The experimental results of Ag PbmSb Tem _ 2 polycrystalline solid micron spheres as anode materials for lithium ion batteries were summarized. The results of Ag PbmSb Tem _ 2 polycrystalline solid micron spheres as anode materials for lithium ion batteries were summarized in comparison with single doped ternary system and pure Pb Te binary system. The results of the measurements of Ag PbmSb Tem _ 2 polycrystalline solid microspheres as anode materials for lithium ion batteries were summarized. Its excellent electrochemical performance and high cycle stability were demonstrated. In this paper, not only the liquid phase synthesis of Pb Te based and Cu S based materials is investigated, but also the results can be used for reference and guidance for the controllable preparation and study of properties of sulfur nanocrystalline doped system.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O611.4;TB383.1

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