J. Mater. Sci. Technol. ›› 2016, Vol. 32 ›› Issue (2): 147-152.DOI: 10.1016/j.jmst.2015.08.003

• Orginal Article • Previous Articles     Next Articles

Interfacial Synthesis of δ-MnO2 Nano-sheets with a Large Surface Area and Their Application in Electrochemical Capacitors

?Zhijun Jia1, Jun Wang1, Yi Wang1, 2, Bingyang Li3, Baoguo Wang3, Tao Qi1, Xin Wang2   

  1. 1 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
    2 School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore;
    3 Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2015-01-16 Revised:2015-03-25
  • Contact: Ph.D.; Tel.: +86 10 82544967; Fax: +86 10 82544848 E-mail address: wangyi@ipe.ac.cn (Y. Wang).802. Ph.D.; Tel.: +65 6316 8866; Fax: +65 6794 7553. E-mail address: WangXin@ntu.edu.sg (X. Wang).

Abstract: Birnessite-type MnO2 (δ-MnO2) nano-sheets were successfully synthesized by an interfacial synthesis method in this work. The properties and electrochemical performance of the as-prepared δ-MnO2 were analyzed and evaluated by scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption measurement and electrochemical tests. This facile synthesis method enables δ-MnO2 nano-sheets to show a large specific surface area (257.5?m2?g-1). The electrochemical test results show that the specific capacitance is 272?F?g-1 and the specific capacitance retention is over 96.7% after 1000 cycles at a scan rate of 10?mV?s-1. All results demonstrate that δ-MnO2 has a great potential application in high-performance electrochemical capacitors, and this interfacial synthesis method will be a very promising method to synthesize highly active MnO2 materials in a large scale.

Key words: Oxides, Nanostructures, Chemical synthesis, Electron microscopy, Electrochemical properties