• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1323-1327
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• 2001

The catalyst Ni/MgO (Ni : 15 wt%) has been applied to methane reforming reactions, such as steam reforming of methane (SRM), partial oxidation of methane (POM), and oxy-steam reforming of methane (OSRM). It showed high activity and good stability in all the reforming reactions. Especially, it exhibited stable catalytic performance even in stoichiometric SRM (H2O/CH4 = 1). From TPR and H2 pulse chemisorption results, a strong interaction between NiO and MgO results in a high dispersion of Ni crystallite. Pulse reaction results revealed that both CH4 and O2 are activated on the surface of metallic Ni over the catalyst, and then surface carbon species react with adsorbed oxygen to produce CO.

• Current Applied Physics
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• v.18 no.11
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• pp.1345-1351
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• 2018

To allow stable cycling of layered nickel-rich cathode material at high voltage, silyl-functionalized dimethoxydimethylsilane is proposed as a multi-functional additive. In contrast to typical functional additive, dimethoxydimethylsilane does not make artificial cathode-electrolyte interfaces by electrochemical oxidation because it is quite stable under anodic polarization. We find that dimethoxydimethylsilane mainly focuses on scavenging nucleophilic fluoride species that can be produced by electrolyte decomposition during cycling, leading to improving interfacial stability of both nickel-rich cathode and graphite anode. As a result, the cell cycled with dimethoxydimethylsilane-controlled electrolyte exhibits 65.7% of retention after 100 cycle, which is identified by systematic spectroscopic analyses for the cycled cell.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.225-229
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• 2005

We have designed micro-fuel processor system, which consists of a steam reforming area and a PROX(preferential oxidation) area. Micro-fuel processor system generates $H_2$ rich gas from a methanol. In our experiment, we have integrated micro-fuel processor system using low temperature cofired ceramics (LTCC) process because LTCC is superior to other materials principally due to their high thermal and chemical stability, simpler fabrication processes, and lower materials cost. Therefore, we have studied and integrated micro-fuel processor system containing embedded heaters, cavities, and 3D structures of micro-channel with LTCC. Also we have optimized the LTCC process.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.10
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• pp.838-843
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• 2002

Chemical mechanical polishing(CMP) process has been widely used to planarize dielectric layers, which can be applied to the integrated circuits for deep sub-micron technology. The reverse moat etch process has been used for the shallow trench isolation(STI)-chemical mechanical polishing(CMP) process with conventional low selectivity slurries. Thus, the process became more complex, and the defects were seriously increased. In this paper, we studied the direct STI-CMP process without reverse moat etch step using high selectivity slurry(HSS). As our experimental results show, it was possible to achieve a global planarization without the complicated reverse moat process, the STI-CMP process could be dramatically simplified, and the defect level was reduced. Therefore the throughput, yield, and stability in the ULSI semiconductor device fabrication could be greatly improved.

• Journal of the Korean Chemical Society
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• v.16 no.3
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• pp.193-199
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• 1972

Bentones from Korean bentonites were first prepared by reacting bentonites with high molecular weight imidazolines. The cation exchange capacity of bentonites was found more than 100meq/100g sample. Greases were then prepared by dispersing bentones into a lubricating oil and milling through a three-roll dispersion mill. Consistency in microscale, oxidation stability (static), water resistance, and wear property of the greases were tested by the ASTM methods, and good experimental results were obtained.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.250-255
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• 2019

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) show promise for improving the lithium ion battery safety. However, due to oxidation of the PEO group and corrosion of the Al current collector, PEO-based SPEs have not previously been effective for use in $LiCoO_2$ (LCO) cathode materials at room temperature. In this paper, a semi-interpenetrating polymer network (semi-IPN) PEO-based SPE was applied to examine the performance of a LCO/SPE/Li metal cell at different voltage ranges. The results indicate that the SPE can be applied to LCO-based lithium polymer batteries with high electrochemical performance. By using a carbon-coated aluminum current collector, the Al corrosion was mostly suppressed during cycling, resulting in improvement of the cell cycle stability.

• Ceramist
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• v.22 no.3
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• pp.256-268
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• 2019

Ceramic nano pigments have attracted much interest owing to recent demand for nontoxic, heavy metal-free pigments. In general, ceramic pigments must possess thermal stability at high temperature, however nanosized powder easily undergoes aggregation at high temperature, and its color turns. serveral groups have focused on to minimize agglomeration and oxidation, a core-shell structure with a silica coating is suggested. In this review, we introduce the reported the trend of nano-ceramic powders and we summarized method improve color and physical properties throuth morphology control and ceramic coating technology.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.121-121
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• 2018

Copper is a promising electronic material due to low cost and high electrical conductivity. However, the oxidation problem in an ambient condition makes a crucial issue in practical applications. In here, we developed a simple and cost-effective Cu patterning method on a flexible PET film by combining a solution processable Cu nanoparticle patterning and a low temperature post-processing using acetic acid treatment, laser sintering process and acid-assisted laser sintering process. Acid-assisted laser sintering processed Cu electrode showed superior characteristics in electrical, mechanical and chemical stability over other post-processing methods. Finally, the Cu electrode was applied to the flexible electronics applications such as flexible and transparent heaters and touch screen panels.

• KSBB Journal
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• v.11 no.4
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• pp.489-496
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• 1996

Metal dispersed carbon paste electrodes were fabricated, and their electrochemical properties were investigated. Among various metal dispersed carbons, platinum-dispersed carbon paste electrode showed most efficient electrocatalytic characteristics. The overpotential for the oxidation of NADH was significantly lowered in the platinum-dispersed carbon paste electrode, and catalytic current was also enhanced. Based on these electrocatalytic observations, L-lactate biosensor using L-lactate dehydrogenase was constructed to evaluate its performance in terms of sensitivity and stability.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.205-205
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• 2017