Solid Synthesis Of NiFe₂O₄and The Characterization Of Its Anode Performance

The spinel NiFe2O4is a kind of new composite materials, In view of its properties: chemical stability, anti-corrosion, the wearability, thermostable, and so on, it is used for the preparing and researching of inert anode.In this paper, the NiO and Fe2O3is used to prepare by spinel NiFe2O4for high temperature solid-state reaction and added1%of MnO2,0.5%of TiO2and1.5%of V2O5to investigate the effects of different additive for Nickel Ferrite inert anode by AC impedance spectroscopy. In the result, the additives can increase electrical conductivity. In simultaneous, the electrical conductivity and all the result obeys Arrhenius Law, which it is increased with increased temperature. As the additives were added, the activation energy for conduction is decreased. According to experiment, the activation energy for conduction of MnO2, TiO2and V2O5are82.52J/mol,56.11J/mol and8.04J/mol.In this research, the different spinel NiFe2O4which contain mole fraction of0.03%～0.12%of TiO2are used to investigate the effects for electrical conductivity of Nickel Ferrite inert anode by AC impedance spectroscopy; the product characteristics were examined with powder X-ray diffraction (XRD) and the analytical scanning electron microscope (SEM). Measure the AC impedance spectroscopy in NaCl-CaCl2molten salt and anodic polarization curve in NaCl-CaCl2-CaO molten salt of NiFe2O4-xTiO2. In the result, the electrical conductivity is increased in firstly and then it decreased following the increased amount of TiO2. The XRD patterns showed that the composite had characteristic diffraction peaks for NiFe2O4and Ni3TiO5, and it can cause the distortion of unit cell and chance the parameter of unit cell. According to the fitting parameter of AC impedance spectroscopy of NiFe2O4-xTiO2, the NiFe2O4-xTiO2which is prepared under this condition possessed some advantages, which are small porosity in the surface; good connect between the surface of molten salt, pure capacitance in double-layer capacitance and significantly increased conductivity of NiFe2O4with increased temperature of molten salt system. The anodic polarization curve of NiFe2O4-xTiO2reported to added TiO2can decrease anodic over voltage of NiFe2O4-xTiO2in NaCl-CaCl2-CaO molten salt and increased reaction current.