Acta Chim. Sinica ›› 2017, Vol. 75 ›› Issue (2): 218-224.DOI: 10.6023/A16080424 Previous Articles     Next Articles

Special Issue: 先进电池材料



刘丽露, 戚兴国, 胡勇胜, 陈立泉, 黄学杰   

  1. 中国科学院大学物理科学学院 中国科学院物理研究所 北京 100190
  • 投稿日期:2016-08-21 修回日期:2016-11-10 发布日期:2016-11-24
  • 通讯作者: 胡勇胜,;Tel.:010-82649808;Fax:010-82649046
  • 基金资助:


Novel Cu Based Oxides with Tunnel Structure as Cathode for Sodium-ion Batteries

Liu Lilu, Qi Xingguo, Hu Yongsheng, Chen Liquan, Huang Xuejie   

  1. School of Physical Sciences, University of Chinese Academy of Sciences, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2016-08-21 Revised:2016-11-10 Published:2016-11-24
  • Contact: 10.6023/A16080424
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 51222210 and 11234013), and One Hundred Talent Project of the Chinese Academy of Sciences.

Lithium-ion batteries have dominated the electronic and portable device market, since its commercialization in 1990s. However, the cost gets boosted because of the shortage and uneven distribution of lithium. Due to the advantage of cost compared with lithium-ion batteries, sodium-ion batteries are considered as the potential candidates for large scale energy storage systems. Cu based tunnel type materials were first synthesized through simple solid state reaction, with Na2CO3, CuO, Fe2O3, MnO2 and TiO2 as starting materials. These raw materials were weighed and grounded in an agate mortar, followed by heat treatment at 950℃ for 24 h in air. The obtained samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical performance test. The XRD results demonstrate the tunnel structure was formed with space group pbam (the same with Na0.44MnO2) for each compound. SEM observation manifests that the distribution of particle size is from several hundred of nanometers to several micrometers. The specifically designed compound with Mn substitution (Na0.66Cu0.17Mn0.33Ti0.50O2) can deliver 90 mAh/g cycled between 1.5~4.1 V. Good cycling stability was verified for this compound, of which 90% of its capacity maintained after 50 cycles at 0.1C rate. Moreover, the rate capability is also good and 74% of its capacity remained when cycled at 1C rate. Charge transfer mechanism was studied by X-ray photoelectron spectroscopy (XPS), and the electroactivity of Cu3+/Cu2+ in this tunnel structure was proved. In addition, we also performed in-situ XRD in order to examine the structure change during sodium extraction and intercalation. Only solid solution reaction took place during the test with shift of peaks or change of the peaks' intensity, however without the appearance of new peaks or disappearance of existed peaks. Here we report, for the first time, the electroactivity of Cu3+/Cu2+ in tunnel type structure. Our results provide new insights in designing tunnel type compound as cathode material for sodium-ion batteries.

Key words: Cu3+/Cu2+ redox couple, layered structure, tunnel structure, sodium-ion batteries