化工学报 ›› 2017, Vol. 68 ›› Issue (9): 3600-3606.DOI: 10.11949/j.issn.0438-1157.20170342

• 材料化学工程与纳米技术 • 上一篇    下一篇

结构有序的Si/void/C/graphene纳米复合结构的制备及储锂性能

何大方1,2, 李丽鲜1, 白凤娟2, 沈丽明1, 暴宁钟1,2   

  1. 1 南京工业大学化工学院, 材料化学工程国家重点实验室, 江苏 南京 210009;
    2 江南石墨烯研究院, 江苏 常州 213149
  • 收稿日期:2017-03-31 修回日期:2017-06-29 出版日期:2017-09-05 发布日期:2017-09-05
  • 通讯作者: 暴宁钟
  • 基金资助:

    国家自然科学基金项目(51425202,51202110);江苏省自然科学基金项目(BK20160093);常州市科技支撑计划项目(CE20150054,CE20160031);江苏高校品牌专业建设工程项目。

Design, preparation, and lithium-storage properties of ordered Si/void/C/graphene nanocomposites

HE Dafang1,2, LI Lixian1, BAI Fengjuan2, SHEN Liming1, BAO Ningzhong1,2   

  1. 1 State Key Laboratory of Material-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, Jiangsu, China;
    2 Jiangnan Graphene Research Institute, Changzhou 213149, Jiangsu, China
  • Received:2017-03-31 Revised:2017-06-29 Online:2017-09-05 Published:2017-09-05
  • Contact: 10.11949/j.issn.0438-1157.20170342
  • Supported by:

    supported by the National Natural Science Foundation of China (51425202,51202110),the Natural Science Foundation of Jiangsu Province (BK20160093),the Industrial Support Program of Changzhou (CE20150054,CE20160031) and the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP).

摘要:

采用简单的超声、冷冻干燥和热还原相结合的自组装方法,设计和构建了纳米硅核/间隙/无定形碳壳层/石墨烯(Si/void/C/graphene) 三维有序纳米复合结构。在该结构中,纳米硅核与碳壳层之间的空隙有效避免了硅的巨大体积膨胀对碳层的破坏,大幅度提高了锂离子电池的循环稳定性;将Si/void/C纳米结构嵌入在石墨烯层与层之间,利用石墨烯卓越的导电性和柔韧性,进一步缓冲了硅材料的体积效应和提高了复合材料的导电性能。该复合材料在4200 mA·h·g-1(1 C)电流密度下循环1000次后比容量仍高达1603 mA·h·g-1;在67 A·g-1(16 C)的高倍率下,比容量仍有310 mA·h·g-1,显示出了在锂离子电池负极材料领域的巨大应用潜力。

关键词: 硅, 石墨烯, 碳, 复合材料, 纳米材料, 电化学

Abstract:

An ordered three-dimensional Si/void/C/graphene nanostructure composite was constructed by a simple self-assembly method combined with ultrasonication, freeze-drying, and thermal reduction. In this novel nanostructure, Si nanoparticles are completely sealed inside carbon shells with rationally designed void spaces between the Si nanoparticles and the carbon shell, which are in turn embedded in layers of graphene sheets. The well-defined void space allows the Si particles to expand freely without breaking the outer carbon shell. Meanwhile, the graphene layers further reinforce the Si/void/C structure and thus enhance the electrical conductivity of silicon anode material and substantially increase the electrochemical performance of silicon anode material. This novel ordered structure delivers a long-term stability of 1603 mA·h·g-1 over 1000 cycles at a high current density of 4200 mA·g-1 (1 C), and an excellent rate capability of 310 mA·h·g-1 at 67 A·g-1 (16 C), thus exhibiting great potential as an anode composite structure for durable high-rate lithium ion batteries.

Key words: Si, graphene, carbon, composites, nanomaterials, electrochemistry

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