化学学报 ›› 2017, Vol. 75 ›› Issue (2): 206-211.DOI: 10.6023/A16100542 上一篇    下一篇

所属专题: 先进电池材料

研究论文

具有三维导电网络结构的锡纳米颗粒/石墨烯纳米片复合电极材料的储镁性能研究

张长欢a, 李念武a, 姚胡蓉a,b, 刘琳a,b, 殷雅侠a,b, 郭玉国a,b   

  1. a 中国科学院化学研究所 中国科学院分子纳米结构与纳米技术重点实验室 北京 100190;
    b 中国科学院大学 化学与化工学院 北京 100049
  • 投稿日期:2016-10-13 修回日期:2016-12-19 发布日期:2016-12-20
  • 通讯作者: 殷雅侠,E-mail:yxyin@iccas.ac.cn;郭玉国,E-mail:ygguo@iccas.ac.cn;Tel.:010-82617069;Fax:010-82617069 E-mail:yxyin@iccas.ac.cn;ygguo@iccas.ac.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.51225204,21303222,21127901)和中国科学院战略性先导科技专项(XDA09010100)资助.

Synthesis of Sn Nanoparticles/Graphene Nanosheet Hybrid Electrode Material with Three-Dimensional Conducting Network for Magnesium Storage

Zhang Changhuana, Li Nianwua, Yao Huronga,b, Liu Lina,b, Yin Yaxiaa,b, Guo Yuguoa,b   

  1. a CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences(CAS), Beijing 100190, China;
    b School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2016-10-13 Revised:2016-12-19 Published:2016-12-20
  • Contact: 10.6023/A16100542 E-mail:yxyin@iccas.ac.cn;ygguo@iccas.ac.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51225204, 21303222, and 21127901) and the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA09010100).

镁二次电池具有安全性高、价格低廉等优点,是一种具有潜在应用前景的高能量密度电池体系.目前,镁二次电池的研究重点之一是寻找合适的电极材料.最近,我们通过水热和热处理相结合的方法成功制备了具有三维导电网络结构的锡纳米颗粒/石墨烯纳米片复合电极材料.研究发现,在石墨烯的三维导电网络片层上,均匀分布了粒径小于100 nm的锡纳米颗粒.将锡纳米颗粒/石墨烯纳米片复合材料作为镁二次电池电极材料,当电流密度为15 mA·g-1和300 mA·g-1时,首次放电容量分别达到了545.4 mAh·g-1和238.8 mAh·g-1,经过150圈后,容量保持率达到了93%,库伦效率为99%,表现出了较高的电化学活性.研究还发现,镁离子嵌入复合材料中形成镁锡合金,当镁离子脱出后,再次形成锡纳米颗粒/石墨烯纳米片复合电极材料,镁离子的脱出和嵌入具有很高的可逆性.这对未来研究设计高性能镁离子电极材料具有十分重要的意义.

关键词: 储镁材料, 镁二次电池, 纳米复合材料, 三维导电网络, 锡纳米颗粒, 石墨烯纳米片

Rechargeable magnesium (Mg) batteries have attracted research attention as one promising alternative for energy storage because of abundant raw materials. However, the strong electrostatic interaction between bivalent Mg-ions and host lattices often cause sluggish solid state diffusion of Mg-ion within the local crystal structure and consequently prevent reversible insertion/extraction of Mg-ion. Thus much more effort has been paid to develop suitable electrode materials with Mg-ion storage capability. This paper reports the synthesis of Sn nanoparticles/reduced-graphene-oxide nanosheet hybrid nanocomposite (Sn/rGO), by simple hydrothermal method and subsequent thermal treatment. Transmission electron microscopy (TEM) clearly shows that in the as-synthesized Sn/rGO powder Sn nanoparticles are well crystallized, and X-ray diffraction (XRD) pattern was consistent well with tetragonal Sn. Thermogravimetric analysis (TG) suggested that the mass percentage of Sn is ca. 82.3 wt% in the Sn/rGO nanocomposite, very close to the design ratio of ca. 83.4 wt%. As Mg-ion battery anode, the Sn/rGO electrode material exhibit a high initial discharge specific capacity (545.4 mAh·g-1 at 15 mA·g-1), good reversible ability and rate performance. The impressive electrochemical property could be attributed to the unique structure of Sn/rGO, in which the three-dimensional (3D) conducting network of rGO can effectively prevent the aggregation of Sn nanoparticles and alleviate the serious volume variation of Sn during repeated discharging/charging process, as well as facilitate the fast access of electrons and Mg-ion to improve kinetics for Mg-ion insertion/extraction. Ex situ XRD and SEM characterization were performed to investigate the electrochemical evolution of Sn/rGO electrode at different discharging/charging states. It is found that upon magnesiation crystalline Mg2Sn appears and subsequently disappears during de-magnesiation process, which indicates the good electrochemical activity of Sn nanoparticles in Sn/rGO hybrid nanocomposite for magnesium storage. Our result will open new avenue to develop high-efficient magnesium storage material for rechargeable Mg batteries.

Key words: magnesium storage, rechargeable magnesium battery, nanocomposite, conducting network, tin, graphene