上海大学学报(自然科学版) ›› 2020, Vol. 26 ›› Issue (4): 586-594.doi: 10.12066/j.issn.1007-2861.2056

• 研究论文 • 上一篇    下一篇

中空硅球/石墨烯复合材料制备及电化学性能

高阳, 蒋永, 焦正()   

  1. 上海大学 环境与化学工程学院,上海 200444
  • 收稿日期:2018-05-02 出版日期:2020-08-30 发布日期:2020-01-31
  • 通讯作者: 焦正 E-mail:zjiao@shu.edu.cn

Preparation and electrochemical performance of hollow silicon sphere/graphene composite electrodes

GAO Yang, JIANG Yong, JIAO Zheng()   

  1. School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
  • Received:2018-05-02 Online:2020-08-30 Published:2020-01-31
  • Contact: JIAO Zheng E-mail:zjiao@shu.edu.cn

摘要:

锂离子电池中硅基负极材料具有极高理论容量和低充放电电压平台,作为代替石墨的最佳负极材料,成为当下研究中热门的锂电池负极材料。设计中空硅球/石墨烯复合材料,H-Si 球与氧化石墨烯水热条件下形成三维多孔石墨烯气凝胶内嵌硅球复合物(H-Si/GA),H-Si 球与聚二烯丙基二甲基氯化铵(poly dimethyl diallyl ammonium,PDDA)功能化的氧化石墨烯溶剂热条件下静电吸附形成包覆状复合物(H-Si/G)。借助结构表征和电性能测试,硅球与石墨烯紧密包覆状的 H-Si/G 展示出更佳的电性能。中空硅球由于静电吸附作用嵌入石墨烯纳米片中,石墨烯牢牢固定硅球,构建了稳定的导电通道,缓冲体积膨胀,并保持电极结构稳定。硅球内部的空隙空间为体积膨胀预留足够缓冲空间,缩短了电子和离子传输通道。

关键词: 硅碳复合材料, 中空硅球, 石墨烯气凝胶, 锂离子电池

Abstract:

The silicon material of lithium-ion batteries with high theoretical capacity and low charge-discharge voltage platform, serving as the best anode material to replacing graphite, has become the most popular material for research. H-Si spheres and graphene oxide solutions form a three-dimensional porous graphene aerogel embedded silicon sphere nanocomposite (H-Si/GA) using hydrothermal reaction. H-Si spheres and positive graphene functionalizing with poly dimethyl diallyl ammonium (PDDA) electrostatically absorbed form a coating-like nanocomposite (H-Si/G) using solvothermal reaction. It was found that H-Si/G has better electrical properties because of compact coating through structural characterization and electrical performance tests. The hollow silicon spheres are embedded in the graphene nanosheets due to electrostatic adsorption. Graphene firmly fixes the silicon spheres, establishes stable conductive paths, buffers volume expansion and maintains electrode structure stability. And the void space inside the silicon spheres provides sufficient buffer space for volume expansion and shortens the electron and ion transmission channels.

Key words: silicon-carbon nanocomposites, hollow silicon spheres, graphene aerogels, Lithium-ion batteries

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