This paper proposed a "top-down" and high-efficient process route to produce Si nanostructures with semiconductor compound machining method. First of all ,the micro/submicro Si , particle mean size (D50) of which is about 1.45 μm,intermediate products are efficiently fabricated from heavily doped boron silicon ingot by means of spark discharge method. Subsequently ,the particle size can be further reduced to dozens of nanometers using high-energy ball milling ,and the particle mean size (D50) is approximately 60 nm. The first time discharge specific capacity of the micro/submicro Si is extremely high,which is more than 3500 mAh/g. However,after 65 cycles,reversible capacity of the Si-based electrode maintains at about 300 mAh/g ,which corresponds to 15% capacity retention. As a contrast,the first time discharge specific capacity of the nano-Si is 2717.3 mAh/g. And after 65 cycles,reversible capacity of the Si-based electrode maintains at about 1458.6 mAh/g,which corresponds to 66.84%capacity retention.%提出一种高质高效、自上而下的纳米硅制备方法,从半导体复合加工方法入手,以重掺杂晶体硅为原料,采用火花放电法高效预制备微米/亚微米硅材料,其平均粒径(D50)约1.45μm,进而通过高能球磨法将尺寸缩减至数十纳米,获得尺寸均布、平均粒径(D50)约60 nm的硅颗粒.微米/亚微米硅材料首次放电比容量较高,超过3500 mAh/g,但经65次循环,电极的可逆比容量仅剩300 mAh/g,容量保持率不足15%.纳米硅颗粒首次放电比容量为2717.3 mAh/g,经65次循环,电极的可逆比容量仍保持有1458.6 mAh/g,容量保持率高达66.84%.
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