Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (5): 899-907.doi: 10.3866/PKU.WHXB201403261

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Synthesis of a MnO2/NiCo2O4 Composite by Electrostatic Self-Assembly and Its Electrochemical Performance

LI Li1,2, HU Zhong-Ai1, YANG Yu-Ying1, WU Hong-Ying1, CUI Lu-Juan2   

  1. 1 Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China;
    2 College of Chemical Engineering, Northwest University for Nationalities, Lanzhou 730030, P. R. China
  • Received:2013-12-12 Revised:2014-03-26 Published:2014-04-25
  • Contact: HU Zhong-Ai E-mail:zhongai@nwnu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20963009, 21163017), Specialized Research Fund for the Doctoral Program of Higher Education, China (20126203110001), and Fundamental Research Funds for the Central Universities, China (zyz2012064).

Abstract:

A hetero-layered MnO2/NiCo2O4 composite was fabricated according to an electrostatic self-assembly process between negatively charged MnO2-layered nanosheets and positively charged Co-Ni-layered double hydroxide nanosheets, followed by a heat-treatment process. The morphology, composition, and microstructure characteristics of the resulting material were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectrometry, atomic absorption spectrometry (AAS), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Furthermore, the electrochemical behaviors of the composite were evaluated by cyclic voltammetry (CV), galvanostatic chargedischarge, and electrochemical impedance spectroscopy (EIS). The test results indicated that the hetero-layered composite showed porous stacking structure, which increased the effective liquid-solid interfacial area, and provided a fast path for the insertion and extraction of electrolyte ions. A specific capacitance of 482 F·g-1 was obtained in the potential window from-0.6 to 0.45 V at a current density of 1 A·g-1. These values were therefore superior to those of pure MnO2 or pure NiCo2O4.

Key words: Electrostatic self-assembly, MnO2, NiCo2O4, Layered stacking structure, Electrochemical performance

MSC2000: 

  • O646