• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.12
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• pp.2235-2239
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• 2010

In this study, The cation exchange membrane and the anion exchange membrane affect in electrical conduction of metal fuel cell was investigated. Magnesium material as anode electrode and the NaCl solution dissolved with 5~15wt% as electrolyte were used for the metal fuel cell. It was found that magnesium slag where flows toward the air electrode was suppressed by using ion exchange membrane. The open circuit voltage variation during discharge has very flat pattern by using ion exchange membrane, but the case which is not the exchange membrane, the open circuit voltage increased according to time. When using the anion exchange membrane, the electric current was higher case of the cation exchange membrane, as a result of higher equivalent conductivity in anion Cl-. The cation exchange membrane was observed with the fact that the output power is excellent in compared with anion exchange membrane.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.77-82
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• 2011

In this study, a metal-supported SOFC was fabricated using a relatively cheap and simple process. The adhesion process between ceramic cell and metal support was performed in high temperature over $1400^{\circ}C$ and the deformation of large metal-supported cell happened in this process. Using bi-layered metal support fabricated by diffusion bonding, the deformation of the metal-supported cell can be minimized and the sealing efficiency of anode and cathode was improved. The flatness of the cell was improved by over 20% and the maximum power density of over 0.5 $Wcm^{-2}$ was obtained at the operation condition of $800^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.48 no.2
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• pp.68-72
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• 2015

The corrosion behavior of metals and alloys for the safety of offshore structures in seawater was investigated for the application of sacrificial anodes. The experiments were focused on the polarization behaviors and the surface morphology of each metal after experiments. Pure Zn, pure Al (Al1050), Al alloys (Al5052, Al6061), Mg alloys (AZ31, AZ91D) and steel (SCM440) were assessed in 3.5% sodium chloride solution by means of potentiodynamic polarization to verify the galvanic corrosion potential ($E_{couple}$). Potentiostat plots were plotted to compare the surface and corrosion current density ($i_{couple}$) of metals as sacrificial anodes in seawater to protect steel alloy as a cathode. Al alloys showed the best performance as a sacrificial anode, on the other hand, Mg alloys showed overprotection behavior. The surface morphologies of sacrificial anodes were observed by FESEM and compared.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.377-384
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• 2007

This study has carried out a performance of dimensionally stable anode for the purpose of decolorization of Rhodamine B (RhB) in water. Seven kinds of 1, 2 and 3 component electrodes were prepared by plating and thermal deposition, which were coated by the oxides of Pt, Ru, Ir, Sn-Sb, Ir-Sn-Sb, Ru-Sn-Sb and Ru-Sn-Ti on Ti metal surface, respectively. Performance for RhB decolorization of the seven electrodes lay in: Ru-Sn-Ti/Ti ${\fallingdotseq}$ Ru-Sn-Sb/Ti > Ir-Sn-Sb/Ti > Sn-Sb/Ti > Ru/Ti > Ir/Ti > Pt/Ti. The effects of electrode area and distance, electrolyte type and concentration, current density and pH were investigated on the decolorization of RhB using Ru-Sn-Ti/Ti electrode. Decolorization of RhB was not influenced by electrode area and distance largely, however wattage was influenced by them. NaCl was superior to the decolorization of RhB than $Na_2SO_4$. Optimum NaCl dosage and current density were 0.5 g/L and $0.183A/cm^2$, respectively. The pH effect of decolorization of RhB was not significant within the range of 3-7.

• Korean Journal of Materials Research
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• v.28 no.6
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• pp.337-342
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• 2018

Using a high pressure homonizer, we report on the electrochemical performance of $Li_4Ti_5O_{12}(LTO)$ particles manufactured as anode active material for lithium ion battery. High-pressure synthesis processing is performed under conditions in which the mole fraction of Li/Ti is 0.9, the synthesis pressure is 2,000 bar and the numbers of passings-through are 5, 7 and 10. The observed X-ray diffraction patterns show that pure LTO is manufactured when the number of passings-through is 10. It is found from scanning electron microscopy analysis that the average size of synthesized particles decreases as the number of passings-through increases. $LiCoO_2-based$ active cathode materials are used to fabricate several coin half/full cells and their battery characteristics such as lifetime, rate capability and charge transfer resistance are then estimated, revealing quite good electrochemical performance of the LTO particles as an effective anode active material for lithium secondary batteries.

• Korean Journal of Materials Research
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• v.29 no.12
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• pp.757-763
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• 2019

A stacked high-voltage (900 V) Al electrolytic capacitor made with ZrO₂ coated anode foils, which has not been studied so far, is realized and the effects of Zr-Al-O composite layer on the electric properties are discussed. Etched Al foils coated with ZrO₂ sol are anodized in 2-methyl-1,3-propanediol (MPD)-boric acid electrolyte. The anodized Al foils are assembled with stacked structure to prepare the capacitor. The capacitance and dissipation factor of the capacitor with ZrO₂ coated anode foils increase by 41 % and decrease by 50 %, respectively, in comparison with those of Al anode foils. Zr-Al-O composite dielectric layer is formed between separate crystalline ZrO₂ with high dielectric constant and amorphous Al₂O₃ with high ionic resistivity. This work suggests that the formation of a composite layer by coating valve metal oxide on etched Al foil surface and anodizing it in MPD-boric acid electrolyte is a promising approach for high voltage and volume efficiency of capacitors.

• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.228-233
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• 2016

It is hard to employ the carbon materials or the lithium metal foil for the anode of lithium sulfur batteries because of the poor passivation in ether-based electrolytes and the formation of lithium dendrites, respectively. Herein, we investigated the electrochemical characteristics of lithium sulfur batteries with lithiated silicon anode in the liquid electrolytes based on ether solvents. The silicon anodes were lithiated by direct contact with lithium foil in a 1M lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) solution in 1,2-dimethoxyethane (DME) and 1,3-dioxolane (DOL) at a volume ratio of 1:1. They were readily lithiated up to ~40% of their theoretical capacity with a 30 min contact time. In particular, the carbon mesh reported in our previous work was employed in order to maximize the performance by capturing the dissolved polysulfide in sulfur cathode. The reversible specific capacity of the lithiated silicon-sulfur batteries with carbon mesh was 1,129 mAh/g during the first cycle, and was maintained at 297 mAh/g even after 50 cycles at 0.2 C, without any problems of poor passivation or lithium dendrite formation.

• Journal of Electrochemical Science and Technology
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• v.8 no.2
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• pp.124-132
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• 2017

The performance of electrolytic processes using copper and catalyzed electrodes for enhanced nutrient removal with various catalyzers and combinations of electrodes was evaluated. The catalyzed electrodes removed more ammonia nitrogen than the copper electrode, but higher ammonia removal was achieved using a Pt/Ti anode. On the other hand, electrolysis using the Pt/Cu anode consumed less energy and cost less. During electroreduction, nitrate was better removed by a pair of copper electrodes than by the catalyzed electrodes. During electrolysis of synthetic wastewater, ammonia removal not only increased owing to direct oxidation at the anode, but was also influenced by indirect oxidation at the cathode. Platinum-coated copper and titanium cathodes actively produced oxidizers and thus removed more ammonia than a pure metal cathode. Although phosphorus was removable irrespective of the type of catalyzer, electrocoagulation using the copper electrode achieved complete removal of phosphorus in a period of less than 10 min.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.31-32
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• 2007

Built-in voltage in organic light-emitting diodes was studied using modulated photocurrent technique ambient conditions. A device was made with a structure of anode/$Alq_3$/cathode to study a built-in voltage. An ITO was used as an anode, and $Li_2O$/Al was used as a cathode. From the bias voltage-dependent photocurrent, built-in voltage of the device is determined. The applied bias voltage when the magnitude of modulated photocurrent is zero corresponds to a built-in voltage. Built-in voltage in the device is generated due to a difference of work function of the anode and cathode. It was found that for 0.5nm thick $Li_2O$ layer built-in voltage is the higher than the others. It indicates that a very thin alkaline metal compound $Li_2O$ lowers an electron barrier height.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.9-22
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• 2023

Spin-off pyroprocessing technology and inert anode materials to replace the conventional carbon-based smelting process for critical materials were introduced. Efforts to select inert anode materials through numerical analysis and selected experimental results were devised for the high-throughput reduction of oxide feedstocks. The electrochemical properties of the inert anode material were evaluated, and stable electrolysis behavior and CaCu generation were observed during molten salt recycling. Thereafter, CuTi was prepared by reacting rutile (TiO₂) with CaCu in a Ti crucible. The formation of CuTi was confirmed when the concentration of CaO in the molten salt was controlled at 7.5mol%. A laboratory-scale electrorefining study was conducted using CuTi(Zr, Hf) alloys as the anodes, with a Ti electrodeposit conforming to the ASTM B299 standard recovered using a pilot-scale electrorefining device.