| Supercapacitors draw more attentions due to the merits of high power density, fast charge discharge rate, long cycle lifetimes, environment friendly and safe in practice applications. However, the low energy density compared to battery is always a shortcoming. How to design and exploit a novel nanoscaled electrode plays an important role in promoting the electrochemical performance of supercapacitors. The pseudocapacitive electrode based on transition metal oxide possesses higher specific capacitance and becomes a promising electrode materials, but the poor conductive of the metal oxide restricts the electrochemical performance. Recently, some researchers devote themselves into adding conductivity enforcement nanomaterials into the electrode to improve the conductivity of the metal oxide. The problem of using this method is the weak interface bonding force between the current collector and the active materials.The effective way to solve the poor conductivity and the weak interface bonding force is self-grow a thin layer of the active metal oxide on the nanoporous metal(NPM) which has high conductivity and specific surface area. In this paper, we introduce the cobalt oxide with high stability and high specific capacitance based on binary NiMn and ternary NiCuMn oxy-hydroxide electrodes to prepare a novel ternary NiCoMn oxy-hydroxide and research the performance. Meanwhile, we also add some of iron to make low-cost NiFeMn and NiCuFeMn oxy-hydroxide electrode. The research contents as follows:(1) The thickness of 25um ternary single-phase alloy ribbon precursors of different systerm are prepared successfully according to the phase diagram. The tests of EDX and XRD characterization show that they are single-phase alloy and this kind of uniform composition is helpful to form three-dimensional structure.(2) Through control the different conditions of dealloy, we successfully prepared the three-dimensional and bicontinuous structure. XPS characterization shows that the metal elements exist different valence state with different system. Analyzing of the combination of oxygen, there are three different binding form, among them the content of metal oxide and hydroxide is high to improve the electrochemical properties. In the BET characterization, the pore size distribute uniformly between lnm and 10nm.The electrode based Ni20Co10Mn70 alloy has the highest specific capacitance of 48m2/g, which is useful to loading more active materials. The result of the pore size in TEM test is consistent with BET characterization. We can not only finding the pores in the TEM speculum but also observing two different phase in it. These methods of analysis and testing proved that a thin layer of mixed-valence oxide/hydroxide loads on the uniform nanoporous alloy.(3) Comparison of different system, NiFeMn based electrode have low specific capacitance. But compared to the electric double layered capacitance, the specific capacitance of 921F/cm~3 also much higher and hold advantage in the volumetric capacitance. Through the electrochemical performance test of NiCoMn system, the electrode based Ni20Co 10Mn70 alloy has the best performance:the potential window can reach up to 1.5V without hydrolysis; the volumetric capacitance can reach up to 2012F/cm~3 and the energy density can reach up to 114mWh/cm~3at the current density of 1 A/cm~3, meanwhile keeping 20mW/cm~3 of the power density.
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