| Along with the development of the society, due to the consumption of the energy, the research for finding new and efficient energy storage devices attract much attentions. The preparation condition and microstructures of the electrode materials have important effects on the performance of energy storage devices. Among all the electrode materials, Ni-based materials exhibit promising prospect and have been used widely. Especially, the theory capacitance of Ni（OH）2 is 2082 Fg-1. The Ni-based materials, including Ni（OH）2 and NiMn layered double hydroxide, have been studied in this paper. In addition, their application on the energy storage have been explored. Through the combination with g-C3N4 or carbon cloth, the microstructure of the hybrid materials can be adjusted to provide convenient path for the electron, thus the hybrid materials can have a better electrochemical property. At last, the possible reaction mechanism is proposed.The g-C3N4 was fabricated by using pyrolysis method. The hybrid materials were performed with the g-C3N4 as substrate and Ni（CH3COO）2 ? 4H2 O as precursor by using hydrothermal method under 180℃. The structure, composition, morphology and electrochemical properties of as-prepared samples have been studied. It could be concluded that: due to the high surface energy, the Ni（OH）2 individual plate tended to self-assemble to form 3D flower-like when introduced g-C3N4. The 3D flower-like structure could improve bigger contact area with electrolyte and shorter transport/diffusion path lengths for both ions and electrons. Finally, the capacitance was calculated to be 505.6 Fg-1 at a current density of 0.5 Ag-1.The preparation conduction of NiMn layered double hydroxide was explored. The structure and electrochemical property were discussed by varying the hydrothermal temperature and the ration of the Ni precursor and Mn precursor. It was revealed that the hydrothermal temperature and the precursor ration had apparent effects on the structure of electrode materials. The result showed that excellent electrode materials could be obtained when the precursor of Ni and Mn were about 3:1, and the hydrothermal temperature were 100℃, respectively.According to the work we had done, the NiMn layered double hydroxide was obtained under proper ration of the precursor of Ni and Mn and suitable temperature of 100℃. The properties of electrode materials were discussed by varying the alkali precursor, named HMTA and urea. Some works had been done to explore their structure, morphology and electrochemical properties. The results were as follows: the honeycomb-like NiMn-LDH was obtained by using the HMTA as alkali precursor, and the storage energy of honeycomb-like NiMn-LDH was 2.687 C cm-2(2239 Fg-1) at a current density of 5 mA cm-2. To further demonstrate the electrochemical properities of NiMn-LDH, an asymmetric SC device was assembled by using NiMn-LDH as the positive electrode, named NiMn-LDH/CC// EACC-3. Based on the discharge curve, the areal capacitance of the whole device was calculated to be 104.9 mF cm-2 at 1.5 mA cm-2. |
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