物理化学学报 >> 2015, Vol. 31 >> Issue (5): 913-919.doi: 10.3866/PKU.WHXB201503162

电化学和新能源 上一篇    下一篇

还原氧化石墨烯/TiO2复合材料在钠离子电池中的电化学性能

许婧, 杨德志, 廖小珍, 何雨石, 马紫峰   

  1. 上海交通大学化学化工学院, 上海电化学能源器件工程技术研究中心, 上海200240
  • 收稿日期:2014-11-27 修回日期:2015-03-13 发布日期:2015-05-08
  • 通讯作者: 廖小珍 E-mail:liaoxz@sjtu.edu.cn
  • 基金资助:

    上海市自然科学基金(15ZR1422300), 国家自然科学基金(21336003, 21073120, 21006063)和国家重点基础研究发展计划(973)(2014CB239700) 资助项目

Electrochemical Performances of Reduced Graphene Oxide/Titanium Dioxide Composites for Sodium-Ion Batteries

XU Jing, YANG De-Zhi, LIAO Xiao-Zhen, HE Yu-Shi, MA Zi-Feng   

  1. Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
  • Received:2014-11-27 Revised:2015-03-13 Published:2015-05-08
  • Contact: LIAO Xiao-Zhen E-mail:liaoxz@sjtu.edu.cn
  • Supported by:

    The project was supported by the Natural Science Foundation of Shanghai, China (15ZR1422300), Natural Science Foundation of China (21336003, 21073120, 21006063), and National Key Basic Research Program of China (973) (2014CB239700).

摘要:

二氧化钛(TiO2)作为有前景的钠离子电池负极材料, 具有良好的循环稳定性, 但由于其导电率较低, 而导致容量和倍率性能不佳限制了其实际应用. 本文采用喷雾干燥技术制备了氧化石墨烯/纳米TiO2复合材料(GO/TiO2), 通过热处理获得还原氧化石墨烯/TiO2复合材料(RGO/TiO2). 电化学测试结果表明, 还原氧化石墨烯改性的RGO/TiO2复合材料的电化学性能得到显著提升, RGO含量为4.0%(w)的RGO/TiO2复合材料在各种电流密度下的可逆容量分别为183.7 mAh·g-1 (20 mA·g-1), 153.7 mAh·g-1 (100 mA·g-1)和114.4 mAh·g-1 (600mA·g-1), 而纯TiO2的比容量仅为93.6 mAh·g-1 (20 mA·g-1), 69.6 mAh·g-1 (100 mA·g-1)和26.5 mAh·g-1 (600mA·g-1). 4.0%(w) RGO/TiO2复合材料体现了良好的循环稳定性, 在100 mA·g-1电流密度下充放电循环350个周期后, 比容量仍然保持146.7 mAh·g-1. 同等条件下, 纯TiO2电极比容量只有68.8 mAh·g-1. RGO包覆改性极大提高了TiO2在钠离子电池中的电化学嵌钠/脱钠性能. RGO包覆改性技术在改进钠离子电池材料性能中将有很好的应用前景.

关键词: 二氧化钛, 还原氧化石墨烯, 负极材料, 钠离子电池

Abstract:

Anatase TiO2 shows excellent long-term cycling stability as an anode for sodium-ion batteries. However, the low specific capacity and poor rate capability resulting from its intrinsic low electrical conductivity limit its applications. In this work, TiO2 nanoparticles were coated with reduced graphene oxide (RGO) using a combination of spray-drying and heat treatment. Electrochemical tests showed that the obtained RGO/TiO2 composites had improved electrochemical performances. The reversible capacities of the RGO/TiO2 [4.0% (w)] composites were 183.7 mAh·g-1 (20 mA·g-1), 153.7 mAh·g-1 (100 mA·g-1), and 114.4 mAh·g-1 (600 mA·g-1). Bare TiO2 showed low capacities of 93.6mAh·g-1 (20mA·g-1), 69.6mAh·g-1 (100mA·g-1), and 26.5mAh·g-1 (600 mA·g-1). The 4.0%(w) TiO2/RGO composites exhibited good cycling stability with a charge capacity of 146.7 mAh·g-1 at a current density of 100 mA·g-1 after 350 cycles, compared with 68.8 mAh·g-1 for bare TiO2. RGO modification is a promising method for improving the electrochemical performances of the sodium energystorage materials.

Key words: Titanium dioxide, Reduced graphene oxide, Anode material, Sodium ion battery