Silicon/carbon composites have been successfully synthesized via high-energy mechanical milling and following pyrolysis of silicon monoxide/sucrose mixture.X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) are used to evaluate the composite, indicating that the obtained nano-sized (less to 50 nm) crystal silicon particles are homogenously dispersed in carbon matrix.The cycling performance of the composites is excellent, and reversible capacity is 650 mAh ·g-1 after 50 cycles with average capacity fading ratio of 0.27％ per cycle.Small absolute volume changes of in-situ formed nano-silicon particles, better buffering effect of carbon matrix and enhanced electrical conductivity are responsible for the superior electrochemical performance.%以一氧化硅和蔗糖为原料,通过高能球磨和后续热解原位制备硅/碳复合材料.采用X射线衍射仪(XRD)和高分辨透射电子显微镜(HRTEM)对其进行了表征,得到的纳米(小于50 nm)硅颗粒均匀地分散于无定形碳基体中.复合材料电极电化学测试显示,循环50次其可逆容量仍保持在650 mAh·g-1以上,平均每次容量衰减率仅为0.27%.优异的电化学性能主要归因于原位生成的纳米硅颗粒处于无定形碳基体中对其体积变化具有良好的缓冲作用及纳米硅颗粒周围的石墨相对于导电性的改善.
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