摘要
以纳米硅粉为活性材料,乙炔为碳源,通过化学气相沉积(CVD)一步法原位制得核壳结构可控的三维硅/多孔碳纳米复合材料。透射电子显微镜(TEM)和热重分析(TGA)结果表明,制备了厚度可控的无定形碳包覆纳米硅颗粒核壳结构,并形成串珠状三维导电网络。以200 m A/g在0.01~1.00 V循环100次,复合材料中硅的可逆比容量保持在1 270 m Ah/g。这主要是因为:原位生成的无定形碳可缓冲纳米硅颗粒的体积变化,Li+扩散通道更好;三维网络改善了电子传输性能。
Three-dimensional（3D） silicon/porous carbon composite was synthesized via a one-step facile approach assisted by chemical vapor deposition （CVD）, using nano-silicon as active material and acetylene as carbon source. The porous amorphous carbon coated nano-silicon composite with 3D electrical conducting network was characterized by transmission electron microscopy （TEM） and thermogravimetric analysis（TGA）. The composite used for lithium storage kept a reversible capacity of 1 270 mAh/g （0. 01 -1.00 V,200 mA/g） after 100 cycles calculated based on silicon. The improved energy density and cycling performance could be mainly attributed to the in-situ formed porous amorphous carbon layer of the 3D network with better buffering and electron/ ion conductivity properties.
出处
《电池》
CAS
CSCD
北大核心
2017年第6期328-331,共4页
Battery Bimonthly
基金
国家自然科学基金(51403193)
关键词
锂离子电池
硅/碳复合材料
三维导电网络
化学气相沉积
Li-ion battery
silicon/carbon composite
three-dimensional（3D） network
chemical vaper deposition（CVD）
