• Journal of the Korean institute of surface engineering
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• v.36 no.6
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• pp.437-443
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• 2003

The effects of additive(grain refiner, GR) on process efficiency of the Ni-Fe-P alloy electrodeposition and the material properties of the deposit were investigated. Electrochemical properties of the deposits were investigated using polarization and electrochemical impedance techniques, and the material properties of the deposits were characterized through inductively coupled plasma(ICP), spiral contractometer, XRD, SEM and TEM. When the additive was added into the electrodeposition bath, current efficiency, Ni content and corrosion resistance of the deposit increased, whereas residual stress, surface roughness and grain size of the deposit decreased.

• Journal of the Korean institute of surface engineering
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• v.43 no.5
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• pp.243-247
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• 2010

The micro Vickers hardness and internal stress of Ni-Fe metal thin film synthesized by electrodeposition method at $25^{\circ}C$ were studied as a function of bath composition, and surface microstructure and atomic compositions of thin films were investigated by SEM and EDS. And the shape change of $200\;{\AA}$ Ni-Fe nanowires made using anodic aluminum oxide(AAO) templates by electrodeposition method were observed by SEM as a function of ultrasonic treatment time and bath composition. The Fe deposition contents on the substrate non-linearly increased with Fe ion concentration over total metal ion concentration. In case of low Fe contents film, the grain size is smaller and denser than high Fe contents deposited films, and the micro Vickers hardness increased with Fe contents of electrodeposited films. These results affected the shape change of nanowire after ultrasonic treatments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.557-558
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• 2006

The mechanical properties of micro-hardness and internal stress of Ni-Fe alloy thin film made by electrodeposition method have been measured as a function of bath composition and current density. And also the microstructure of $200{\AA}$ Ni-Fi nanowires made using anodic aluminum oxide(AAO) templates by electrodeposition method have been observed by SEM as a function of ultrasonic treatment time and bath composition.

• Journal of the Korean institute of surface engineering
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• v.54 no.3
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• pp.152-157
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• 2021

The pseudocapacitor has a high energy density characteristic because it accumulates charges through a paradic redox reaction. However, due to its strong insulation properties, metal hydroxides should be designed as structural systems optimized for charge transfer to support fast electron transport. Also, Nickel material is weak to heat and is easily deformed when used as a cathode material, so stability must be secured. In this study, nickel hydroxide was produced by electrodeposition to secure the stability of nickel. Electrodeposition is a synthetic method suitable for growing optimized nickel hydroxide because it allows fine control. Nickel hydroxide (Ni(OH)₂) is a metal hydroxide used as a pseudocapacitor anode due to its high capacitance, electrical conductivity and resistance. Therefore, in order to determine how Ni(OH)₂ nanosheets are formed and what are the optimization conditions, various measurement methods were used to focus on structural growth of nanosheets produced by electrodeposition.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.289-292
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• 2000

In order to evade the patent of Oak Ridge National Laboratory (RABiTS process) and search for more economical process, a new process for producing the biaxially textured Ni tape by electrodeposition has been investigated. Electrodeposition was performed in the modified Watts bath. The crystal orientations of electrodeposited Ni were analysed by X-ray pole figure, ${\phi}$-scan and ${\omega}$-scan. The electrodeposited Ni tape showed cube texture with good out-of plane(< 8${\circ}$) and in-plane alignment(< 20${\circ}$).

• Journal of the Korean institute of surface engineering
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• v.54 no.1
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• pp.37-42
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• 2021

Electrodeposition is a synthetic method that allows fine control of the nucleation and growth factors of metals and is a suitable method for studying the nucleation and growth of Ni(OH)2. Hexa-methylenetetramine (HMT) helps to form Ni(OH)2 nanosheets by increasing the OH- of the nickel precursor solution and helps to improve the electrochemical properties of the electrode. In this study, the structural properties of Ni(OH)2 nanosheets according to the HMT concentration change using electrodeposition were studied. As the concentration of HMT increased, the size and thickness of the Ni(OH)2 nanosheet adsorbed on the surface increased and porosity increased. Also, the Scharifker-Hills nucleation theory model and experimental data were compared. In conclusion, the nanosheet shape of the HMT 7.5 mM sample electrodeposited with -0.85 V vs. Ag/AgCl grew most uniformly, and the best result was obtained as an electrode material for a pseudocapacitor.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.125-130
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• 2002

An attempt was made for the application of porous reticular metal to a heat dissipation material in semiconductor process. For this aim, the electrodeposition of Fe/Ni alloy on the porous reticular Cu has been performed to minimize the thermal expansion mismatch between Cu skeleton and electronic chip. Preliminary tests for the electrodeposition of Fe/Ni alloy layer were conducted by using standard Hull Cell to examine the effect of current density on the composition of alloy layer. It seemed that mass transfer affected significantly the composition of Fe/Ni layer due to anomalous codeposition in the electrodeposition of Fe/Ni alloy. A paddle type stirring bath, which was employed to control the mass transfer of electrolyte in the work, was found to allow the electrodeposition Fe/Ni with a precise composition. result showed that the thermal expansion of Fe/Ni alloy layer was much lower than that of pure copper. From the tests of heat dissipation by using the apparatus designed in the work the heat dissipation material fabricated in the work showed the excellent heat dissipation capacity, namely, more than two times as compared to that of pure copper plate.

• Korean Journal of Materials Research
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• v.27 no.11
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• pp.624-630
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• 2017

In this study, we investigated the overpotential of precipitation related to the catalytic activity of electrodes on the initial process of electrodeposition of Co and Co-Ni alloys on polycrystalline Cu substrates. In the case of Co electrodeposition, the surface morphology and the magnetic property change depending on the film thickness, and the relationship with the electrode potential fluctuation was shown. Initially, the deposition potential(-170 mV) of the Cu electrode as a substrate was shown, the electrode potential($E_{dep}$) at the $T_{on}$ of electrodeposition and the deposition potential(-600 mV) of the surface of the electrodeposited Co film after $T_{off}$ and when the pulse current was completed were shown. No significant change in the electrode potential value was observed when the pulse current was energized. However, in a range of number of pulses up to 5, there was a small fluctuation in the values of $E_{dep}$ and $E_{imm}$. In addition, in the Co-Ni alloy electrodeposition, the deposition potential(-280 mV) of the Cu electrode as the substrate exhibited the deposition potential(-615 mV) of the electrodeposited Co-Ni alloy after pulsed current application, the $E_{dep}$ of electrodeposition at the $T_{on}$ of each pulse and the $E_{imm}$ at the $T_{off}$ varied greatly each time the pulse current was applied. From 20 % to less than 90 % of the Co content of the thin film was continuously changed, and the value was constant at a pulse number of 100 or more. In any case, it was found that the shape of the substrate had a great influence.

• Journal of the Korean institute of surface engineering
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• v.44 no.2
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• pp.68-73
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• 2011

A Ni-W thin-film was synthesized by electrodeposition, and its corrosion resistance and electrical surface conductivity were investigated. Amount of tungsten in the Ni-W thin-film increased linearly with current density during the electrodeposition, and crack-free and low-crystalline Ni-21 at.%W coating layer was obtained. Corrosion resistances of the Ni-W thin-films were examined with an anodic polarization method and a storage test in a strong sulfuric acid solution. As a result, the Ni-21 at.%W thin-film exhibited the greatest corrosion resistance, and maintained the electrical surface conductivity even after the severe corrosion test, which could be applicable as a surface treatment for advanced metallic bipolar plates in fuel cell or redox flow battery systems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.269-270
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• 2009