Characteristics of Mn-Co-Ni Oxide Powders Prepared By Chemical Reduction Method for a Supercapacitor Electrode

Abstract

Supercapacitor is considered as a candidate for the promising energy storage device due to its permanent properties, high power density, and short charging time [1]. It can be used as a backup system, starting power of fuel cell , hybrid vehicle, or large industrial equipment [2]. There are two typical types of supercapacitors. One is electrochemical double layer capacitors (EDLC) utilizing a polarization phenomenon occurring between the surface of electrode and electrolyte. And the other is pseudo-capacitors using high-speed redox reactions. Normally, transition metal oxide and conductive polymer are used as the electrode materials of pseudo-capacitors [3]. Ruthenium [4] and nickel [5] are often studied among various metal electrode. They exhibit excellent performance, but it is difficult to commercially used because of its high price and eco-unfriendly with strong acid or alkali electrolyte. Therefore, manganese has been studied as an alternative materials. Manganese is showing potential to be used as a supercapacitor electrode because of its low price and eco-friendly property. But, the mechanical strength of manganese is weak, so discharge cycle life is relatively short as compared with that of other electrode materials [6]. In addition, manganese oxide is limited used in conditions that require high power because the power density is reduced with increasing contact resistance [7]. In this study, we fabricate alloy of cobalt, nickel, and manganese prepared by chemical reduction method using the reducing agent (N2H4) and the dispersant (C6H5Na3O7) [8]. The unique shape of Mn-Co-Ni oxide powder was formed by combing powder of Mn (plate like), Co (flower like), and Ni (sphere) (Figure. 1). The electrochemical performance of the Mn-Co-Ni oxide was measured with cyclic voltammetry and charge-discharge test. Reference [1] J.R. Miller, P. Simon, Science, 321 (2008) 651-652.[2] S. Sarangapani, B.V. Tilak, C.P. Chen, J. Electrochem. Soc., 143 (1996) 3791-3799.[3] K. Zhang, L.L. Zhang, X.S. Zhao, J. Wu, Chem. Mat., 22 (2010) 1392-1401.[4] J.P. Zheng, P.J. Cygan, T.R. Jow, J. Electrochem. Soc., 142 (1995) 2699-2703.[5] V. Srinivasan, J.W. Weidner, J. Electrochem. Soc., 144 (1997) L210-L213.[6] S.C. Pang, M.A. Anderson, T.W. Chapman, J. Electrochem. Soc., 147 (2000) 444-450.[7] Q. Li, Z.-L. Wang, G.-R. Li, R. Guo, L.-X. Ding, Y.-X. Tong, Nano Lett., 12 (2012) 3803-3807.[8] K.H. Kim, Y.B. Lee, S.G. Lee, H.C. Park, S.S. Park, Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process., 381 (2004) 337-342. Figure 1