• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.533-539
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• 2013

The electrochemical corrosion and passivation of Ni rotating disk electrod in borate buffer solution was studied with potentiodynamic and electrochemical impedance spectroscopy. The mechanisms of both the active dissolution and passivation of nickel and the hydrogen evolution in reduction reaction were hypothetically established while utilizing the Tafel slope, impedance data, the rotation speed of Ni-RDE and the pH dependence of corrosion potential and current. Based on the EIS data, an equivalent circuit was suggested. In addition, carefully measured were the electrochemical parameters for specific anodic dissolution regions. It can be concluded from the data collected that the $Ni(OH)_2$ oxide film, which is primarily formed by passivation, is converted to NiO by dehydration under the influence of an electrical field.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05c
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• pp.75-78
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• 2002

The dielectric properties for Ni electrode multilayer ceramic chip capacitor for Y5V has been studied with $(Ba_{0.93}Ca_{0.07})_m(Ti_{0.82}Zr_{0.18})O_2+MnO_2$ 0.2wt%, $Y_2O_3$ 0.18wt%, $SiO_2$ 0.15wt%, glass frit 1 wt% composition. The m ratio in the range of 1.006 ~ 1.012 have dielectric constant 9,500 ~ 14,500 and insulation resistance 390 ~ 460 $G{\Omega}$. Using the dielectrics, nikel electrode multilayer chip capacitor with Y5V, 104Z in EIA 0603 size specific capacitance were developed.