火花放电和高能球磨组合工艺制备纳米硅颗粒的研究

发布时间：2018-05-31 10:34

本文选题：纳米硅颗粒 + 火花放电　；参考：《南京航空航天大学》2017年硕士论文

【摘要】：纳米硅材料在陶瓷、光学、微电子等领域有着广泛应用。纳米硅颗粒的制备包括化学和物理两种方法。化学制备方法(如化学气相沉积法等)普遍存在反应条件苛刻、工艺路线复杂、可控性差和产量低的缺点,而物理方法(如球磨法等)尚不能满足高效、低成本制备纳米硅的应用需求。本论文从半导体复合加工手段入手,以重掺杂P型单晶硅为原料,采用火花放电法预制备微米/亚微米硅材料,然后采用高能球磨法制备纳米硅材料,实现了一种高质高效、自上而下的纳米硅制备技术路线,并在此基础上,开展了相关电化学性能测试,具体过程如下:1、以重掺杂P型单晶硅(0.01Ω·cm)为工件,铜管为工具电极,采用火花放电法制备出微米/亚微米硅颗粒,粒径(D50)在1.45μm左右;进而通过高能球磨法,选用0.1mm氧化锆磨球,制备出粒径(D50)在88nm左右的纳米硅颗粒,尺寸分布均匀。2、为验证纳米化对硅材料在脱/嵌锂过程中体积效应的改善,针对上述制备的微米/亚微米和纳米硅材料,开展了电化学性能测试,结果如下:微米/亚微米硅材料首次放电比容量较高,超过4000 mAh/g,但经过65次循环,电极的放电比容量仅剩300 mAh/g,容量保持率不足8%;纳米硅材料首次放电比容量为2717.3 mAh/g,经过65次循环,电极的放电比容量仍保持有1458.6mAh/g,容量保持率高达66.84%。
[Abstract]:Nano-silicon materials are widely used in ceramics, optics, microelectronics and other fields. The preparation of nanocrystalline silicon particles includes chemical and physical methods. Chemical preparation methods (such as chemical vapor deposition) generally have the disadvantages of harsh reaction conditions, complex process routes, poor controllability and low yield, while physical methods (such as ball milling) can not meet the high efficiency. Application requirements for low cost preparation of nano-silicon. In this paper, starting with the semiconductor composite processing method, the micron / submicron silicon was prepared by spark discharge method with heavily doped P type monocrystalline silicon as raw material, and then nano-silicon material was prepared by high energy ball milling method, which realized a high quality and high efficiency. On the basis of the top-down preparation technology of nanocrystalline silicon, relevant electrochemical performance tests have been carried out. The specific process is as follows: 1, with heavily doped P-type monocrystalline silicon (0.01 惟 cm) as workpiece and copper tube as tool electrode. The micrometer / submicron silicon particles were prepared by spark discharge method, the diameter of which was about 1.45 渭 m, and then, by high-energy ball milling, 0.1mm zirconia grinding ball was used to prepare nano-silicon particles about 88nm. In order to verify the improvement of volume effect of nanocrystalline silicon in the process of lithium removal and intercalation, electrochemical performance tests were carried out for the micrometer / submicron and nanometer silicon materials. The results are as follows: the first discharge specific capacity of micron / submicron silicon is high, exceeding 4000 mAh/ g, but after 65 cycles, The discharge specific capacity of the electrode is only 300mAh/ g and the capacity retention rate is less than 80.The discharge specific capacity of the nanocrystalline silicon material is 2717.3 mAh/ g for the first time. After 65 cycles, the discharge specific capacity of the electrode remains at 1458.6 mAhs / g, and the capacity retention rate is as high as 66.84g.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ127.2;TB383.1

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