• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.460-465
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• 2013

Plate-shaped inorganic particles are coated onto a stainless steel substrate by the electrophoretic deposition of a precursor slurry which includes the inorganic particles of $Al_2O_3$ and polymer resin in mixed solvents to mimic the abalone shell structure, which is a composite of plate-shaped inorganic particles and organic interlayer binding materials with a layered orientation. The process parameters of the electrophoretic deposition include the voltage, coating time, and conductivity of the substrate. In addition, the suspension parameters are the particle size, concentration, viscosity, conductivity, and stability. We prepared an organic-inorganic composite coating with a high inorganic solid content by arraying the plate-shaped $Al_2O_3$ particles and electrophoretic resin via an electrophoretic deposition method. We analyzed the effect of the slurry composition and the electrophoretic deposition process parameters on the physical, mechanical and thermal properties of the coating layer, i.e., the thickness, density, particle orientation, Young's modulus and thermogravimetric analysis results.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2431-2437
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• 2014

In this study, Ni, Ni-Cu and Ni/Cu catalysts were deposited onto C-fiber textiles via the electrophoretic deposition method, and the growth characteristics of carbon nanofibers on the deposited catalyst/C-fiber textiles were investigated. The catalyst deposition onto C-fiber textiles was accomplished by immersing the C-fiber textiles into Ni or Ni-Cu mixed solutions, producing the substrate by post-deposition of Ni onto C-fiber textiles with pre-deposited Cu, and passing it through a gas mixture of $N_2$, $H_2$ and $C_2H_4$ at $700^{\circ}C$ to synthesize carbon nanofibers. For analysis of the characteristics of the synthesized carbon nanofibers and the deposition pattern of catalysts, SEM, EDS, BET, XRD, Raman and XPS analysis were conducted. It was found that the amount of catalyst deposited and the ratio of Ni deposition in the Ni-Cu mixed solution increased with an increasing voltage for electrophoretic deposition. In the case of post-deposition of Ni catalyst onto substrates with pre-deposited Cu, both bimetallic catalyst and carbon nanofibers with a high level of crystallizability were produced. Carbon nanofibers yielded with the catalyst prepared in Ni and Ni-Cu mixed solutions showed a Y-shaped morphology.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.80-84
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• 1997

In this experiment, A1$_2$O$_3$ thick films were prepared by electrophoretic method using A1$_2$O$_3$ fine Powder of which composition were FA-5-500 and FA-5-900. The growth behavior of A1$_2$O$_3$ thick films were characterized as preparation conditions, such as applied voltage, deposition time and adding conditions. As a result, A1$_2$O$_3$ thick films were successfully fabricated by electrophoretic method on molybdnum plate in which etanol and distilled used were used as a solvent. Deposition conditions for good uniformity of the A1$_2$O$_3$ thick films were applied voltage of 60volts, deposition time of 2 seconds, heat treatment at 1$700^{\circ}C$ for 5 minutes.

• Journal of Korean Vacuum Science & Technology
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• v.3 no.1
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• pp.79-84
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• 1999

the photolithographic patterning on an indium-tin oxide (ITO) glass and the electro-phoretic deposition were combined for preparing the screen of the full-color field emission display(FED). the patterns with a pixel of 400$\mu\textrm{m}$ on the ITO-glass were made by etching the ITO with well-prepared etchant consisting of HCL, H2O, and HNO3. Electrophoretic method was carried out in order to deposit each spherical red (R), green(G), and blue (B) phosphor on the patterned ITO-glass. The process parameters such as bias voltage, salt concentration, and deposition time were optimized to achieve clear boundaries. It was found that the etching process of ITO combined with electrophoretic method was cost-effective, provided distinct pattern, and even reduced process steps compared with conventional processes. The application of reverse bias to the dormant electrodes while depositing the phosphors on the stripe pattern was found to be very critical for preventing the cross-contamination of each phosphor in a pixel.

• Journal of Powder Materials
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• v.14 no.4
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• pp.238-244
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• 2007

The electrophoretic deposition process of Ni nano-particles in organic suspension was employed for self-repairing of heat exchanger tubes. For this purpose, Ni nano-particles prepared by levitational gas condensation method were dispersed into the solution of ethanol with the addition of dispersant Hypermer KD2. For electrophoretic deposition of Ni nano-particles on the Ni alloy specimen, constant electric fields of 20 and 100 V $cm^{-1}$ were applied to the specimen in Ni-dispersed solution. It was found that as electrophoretic deposition proceeds, the size of the pit or crack remarkably decreased due to the agglomeration of Ni nano-particles at the pit or crack. This strongly suggests that the electrophoretic mobility of the charged particles is larger for the damaged part with a higher current value rather than outer surfaces with a lower current value.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.97-100
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• 2004

In this paper, the preparation of BSCCO superconducting wire by electrophoretic deposition method and the effect of suspension medium used with various solvent solutions of ethanol and buthanol for electrophoretic deposition were studied. The preheating technique in vacuum system for the superconducting powders coated on Ag wire was also investigated. As a result, it was confirmed that the preheating technique was very useful to remove the influence of remains affected to the surface conditions of superconducting wire. And the adsorbed solvent solution which was existed between and on the deposited particle surfaces was almost disappeared at the treating conditions of about $10^{-3}$ Torr and around $200^{\circ}C$ in bell-jar system. By measurement of 4-point prove method, the critical current density($J_c$) of BSCCO superconducting wire was obtained at the value of more than $10^4\;A/cm^2$ in liquid $N_2$(77 K, 0 T).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.63-66
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• 2003

The electrophoretic deposition method has the advantage of relatively few fabrication facilities and simple process procedure as well as the economical and technical merit of allowing various forms of deposition and easy control of deposition thickness and wire length. A study, especially electric field and additive, on the optimization method to increase the density of particles and uniformity of their orientation have been performed to overcome the cracking and the porosity problems in the fabricated superconductor.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.160-160
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• 2013

Dye-sensitized solar cells (DSSCs) have attracted much attention because of their moderate light-to-electricity conversion efficiency, easy fabrication, and low cost. At present, platinum (Pt) is used as a counter electrode in DSSCs. However, it is found that Pt dissolves in iodide electrolyte solutions and creates chemical compound such as PtI4 and H2PtI6. Carbon based materials are one of candidates for a counter electrode of DSSCs. We prepare two types of graphite oxides by different chemical treatments; original graphite oxide, hydrazine treated graphite oxide. Each graphite oxide and magnesium nitrate dispersed in deionized water are prepared as solutions for electrophoretic deposition (EPD). Each graphite oxide electrode is deposited on fluorine-doped tin oxide (FTO) substrate by EPD method. Structural and electrochemical properties of each electrode are investigated by field-emission scanning electron microscopy and electrochemical impedance spectroscopy, respectively.

• Bulletin of the Korean Chemical Society
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• v.15 no.1
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• pp.20-22
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• 1994

The preparation of $YBa_2Cu_4O_8$ thick film on Ag substrate by electrophoretic deposition was directly studied. Electrophoretic deposition was carried out in solution, which was composed of presintered $YBa_2Cu_4O_8$ powder, sodium, and 2-propanol as a solvent. The deposited thick films were heat-treated in $O_2$ at 815$^{\circ}$C for 12 hours and at 450$^{\circ}$C for 12 hours. We succeeded in obtaining superconducting $YBa_2Cu_4O_8$ films on Ag substrate. Even though the chemical reactions at the $YBa_2Cu_4O_8$/Ag interface occurred in the range of 10 ${\mu}$m, superconductivity was not depressed. The thickness of the films was in the range of 60-80 ${\mu}$ m. The characteristics of the films were examined by electric resistance measurements, X-ray diffraction, and SEM observations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.107-110
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• 2002

The electrophoretic deposition (EPD) technique have been applied to fabricating superconducting films and wires in former researches of our Lab. However, the particles of EPD films were usually deposited random1y on the metal substrate, the vertically combined a.c and d.c fields were applied to the EPD electrodes for orienting and densifying the particles of high $T_{c}$ superconducting deposition film on the substrate metal. Therefore, the surface states of EPD films by this combined fields could be oriented and affect to the electric properties increasing of superconducting films. The proposed method modified by a.c. assisted field to the conventional electrophoresis system was suitable to obtain improved properties with particle oriented deposition and densification.