【作者】 魏斯毅；

【导师】 唐成春；

【作者基本信息】 华中师范大学 ， 凝聚态物理， 2008， 硕士

【摘要】 低维纳米材料由于他们依赖于形貌和大小而表现出来的独特性质受到广泛关注，纳米技术也被认为是21世纪最具有前途的科研领域。纳米材料的物相、尺寸和颗粒形状等决定其性能和应用，因而其可控制备就显得至关重要。本论文介绍了通过简捷通用的合成方法控制生长并表征了几种具有特殊性能的低维纳米材料，对其性质进行了研究，对其生长机理也进行了相关探讨。（1）通过溶胶-凝胶法制备其前驱体，系统研究了硼和铝摩尔比、反应温度等对硼酸铝纳米晶须生长的影响，摸索出了大尺度合成硼酸铝纳米晶须的最优化条件。在最优条件下，我们得到的Al₄B₂O₉纳米晶须直径在50hm左右，长度在1μm左右；得到的Al₁₈B₄O₃₃纳米晶须直径也在50nm左右，长度在1μm左右。（2）对硼酸铝纳米棒的热稳定性进行了研究，首次发现硼酸铝纳米棒在水热条件下可以分解生成具有分层结构花状的水合氧化铝（AlOOH）纳米建筑，我们也对其形成机理进行了合理的解释。我们发现在制备三维γ-AlOOH分层次纳米建筑中，Al₄B₂O₉纳米棒起着至关重要的作用：增加反应体系化学能、通过分开γ-AlOOH的成核与生长来控制体系饱和度、为反应体系提供铝源。这种简捷的方法和分开成核与生长的思想，可以延伸为制备其他水合氧化物，为工业化生产提供了可能。（3）在研究硼酸铝纳米棒热稳定性的基础上得到线索，首次探索出在水热条件下一个快速大尺度制备纳米水合氧化铝（AlOOH）材料的简捷方法。通过控制反应条件（溶剂、PH值、表面活性剂），大量制备了不同形貌的纳米水合氧化铝（AlOOH）材料，实现了纳米材料的可控生长。这种方法可以延伸为制备其他水合氧化物，且该方法成本低廉，工艺简单，为工业化生产提供了可能。更多还原

【Abstract】 Low-dimensional nanomaterials have been attracting considerable attention due to their interesting properties dependent on size and shape, and the nanotechnology is also highly desirable in 21th century. Beceause of the composition, dimension and the shape of the nanomaterials play a crucial role in their properties and applications, it is necessary to synthesize morphology- and composition-controlled low-dimensional nanomaterials. In this dissertation, we synthesized some low-dimensional nanostructures by some simple controllable methods. The growth mechanisms have also been discussed.1.We have systematically investigated the preparing process of aluminum borate nanowhiskers. According to the synthesis process, we pay much attention to the key effects: the preparation of precursors from sol-gel method, the ratio of Al/B in the precursors, the calcined temperature. Under the optional conditions, The fine Al₄B₂O₉ nanowhiskers with the average diameter of-50 nm and the length of-1um were obtained by the calcination of Al/B-2 xerogel at 1000℃, while the heat treatment at 1100℃for Al/B-1 xerogel gave rise to the Al₁₈B₄O₃₃ nanowhiskers with the average diameter of-50 nm and the length of -1μm. A possible growth mechanism was also proposed.2. A sophisticated production of 3Dγ-AlOOH （boehmite） hierarchical nanoarchitectures built up of nanostrips has been successfully synthesized. The template/substrate-free and surfactant-free synthetic methodology of hierarchical structures of 1D nanostructures reported in this chapter is a simple, inexpensive, scalable, and mild synthetic process. We have also discussed the thermal stability of the Al₄B₂O₉ nanorods under hydrothermal condition. After that, we obtain the conclusion that the addition of the Al₄B₂O₉ nanorods played a key role in the synthesis of such nanoarchitectures, such as increasing the chemical potential of the solution, control the saturation of the solution to separate the nucleation and growth and supply the Al source continuously. Such a facile method and the idea of control nucleation and growth are applicable to synthesize other metal hydroxide hierarchical nanoarchitectures.3. Controlled growth of the nanomaterials was carried out. We catch our clues from the pre-work of our group and my grope about the thermal stability of the Al₄B₂O₉ nanorods under hydrothermal condition, a facile method was firstly proposed to synthesize AlOOH nanomaterials with large yield. According to control the reaction conditions （solution, PH value and surfactant）, A100H nanomaterials with various shapes were synthesized. Such a facile, inexpensive, scalable, and mild method was applicable to synthesize other metal hydroxide hierarchical nanoarchitectures.更多还原