• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.39-46
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• 2006

Highly ordered Li dispersed nickel oxide nanotubes were prepared with anodic aluminum oxide (AAO) template for hydrogen storage. Electron microscope results showed that uniform length and diameter of nickel oxide nanotubes were obtained. The wall thickness and outer diameter of nickel oxide nanotubes are about 40 - 50 nm and 200 - 400 nm, respectively. It was observed that the diameter of nickel oxide nanotubes is bigger than the pore diameter of AAO template. Li dispersed nickel oxide were consisted of nanoflakes and had structures of nanotubes and nanorods. For increasing the hydrogen adsorption and desorption capacity, the Li dispersed nickel oxide nanotubes were fluorinated. The fluorinated Li dispersed nickel oxide nanotubes showed 1.65 wt% of the hydrogen adsorption capacities at 77 K under 47 atm.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.144-149
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• 2004

Porous anodic alumina has been used widely for corrosion protection of aluminum surfaces or as dielectric material in micro-electronics applications. It exhibits a homogeneous morphology of parallel pores which can easily be controlled between 10 and 400nm. It has been applied as a template for fabrication of the nanometerscale composite. In this study, mechanical properties of the AAO structures are measured by the nano indentation method. Nano indentation technique is one of the most effective method to measure the mechanical properties of nano-structures. Basically, hardness and elastic modulus can be obtained by the nano-indentation. Using the nano-indentation method, we investigated the mechanical properties of the AAO structure with different size of nano-holes. In results, we find the hole effect that changes the mechanical properties as size of nano hole.

• Elastomers and Composites
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• v.49 no.3
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• pp.191-198
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• 2014

We synthesized thermoplastic polyurethane elastomer(TPU) with acid group and nano zinc oxide, and characterized their mechanical properties, thermal properties, contact angle and grip property. The effects of the zinc oxide content and size on the physical property of TPU were investigated. When the nano zinc oxide was introduced in TPU with acid group, it had excellent mechanical properties and grip by formation of hydrogen and ionic bonding. The wet slip of TPU with zinc oxide was increased continuously as ionization rate increased due to increase of hydrophilicity and ionic interaction, and mechanical properties were increased with increasing ionization rate up to 50%.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.186-193
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• 2004

Porous anodic alumina has been used widely for corrosion protection of aluminum surfaces or as dielectric material in micro-electronics applications. It exhibits a homogeneous morphology of parallel pores which can easily be controlled between 10 and 400nm. It has been applied as a template for fabrication of the nanometer-scale composite. In this study, mechanical properties of the AAO structures are measured by the nano indentation method. Nano indentation technique is one of the most effective methods to measure the mechanical properties of nano-structures. Basically, hardness and elastic modulus can be obtained by the nano-indentation. Using the nano-indentation method, we investigated the mechanical properties of the AAO structure with different size of nano-holes. In results, we find the hole effect that changes the mechanical properties as size of nano hole.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.240-243
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• 2009

Recently, many researches on the development of super-hydrophobic and anti-reflective surfaces have been concentrated on the fabrication of nano-patterned products. The nano-patterned mold is a key to replicate nano-patterned products by mass production techniques such as injection molding and UV molding. The present paper proposes fabricating nano-patterned mold with cost-effective method. The nano-pattern molded was fabricated by electroforming the anodic aluminum oxide template without E-beam lithography. The final mold with nano-patterns showed the pores with the diameter of $100{\sim}120$ nm and the height of 150 nm was fabricated.

• Analytical Science and Technology
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• v.37 no.1
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• pp.39-46
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• 2024

Alizarin dye, a persistent and hazardous contaminant in aquatic environments, presents a pressing environmental concern. In the quest for efficient removal methods, adsorption has emerged as a versatile and sustainable approach. This study focuses on the development and application of Zinc Oxide/Nickel Oxide (ZnO/NiO) nano-composites as adsorbents for alizarin dye removal. These semiconducting metal oxide nano-composites exhibit synergistic properties, offering enhanced adsorption capabilities. Key parameters affecting alizarin removal, such as contact time, adsorbent dosage, pH, and temperature, were systematically investigated. Notably, the ZnO/NiO nano-composite demonstrated superior performance, with a maximum alizarin removal percentage of 76.9 % at pH 6. The adsorption process followed a monolayer pattern, as suggested by the Langmuir model. The pseudo-second-order kinetics model provided a good fit to the experimental data. Thermodynamic analysis indicated that the process is endothermic and thermodynamically favorable. These findings underscore the potential of ZnO/NiO nano-composites as effective and sustainable adsorbents for alizarin dye removal, with promising applications in wastewater treatment and environmental remediation.

• Journal of Powder Materials
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• v.21 no.4
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• pp.260-265
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• 2014

In this study, in order to increase surface ability of hardness and corrosion of magnesium alloy, anodizing and sealing with nano-diamond powder was conducted. A porous oxide layer on the magnesium alloy was successfully made at $85^{\circ}C$ through anodizing. It was found to be significantly more difficult to make a porous oxide layer in the magnesium alloy compared to an aluminum alloy. The oxide layer made below $73^{\circ}C$ by anodizing had no porous layer. The electrolyte used in this study is DOW 17 solution. The surface morphology of the magnesium oxide layer was investigated by a scanning electron microscope. The pores made by anodizing were sealed by water and aqueous nano-diamond powder respectively. The hardness and corrosion resistance of the magnesium alloy was increased by the anodizing and sealing treatment with nano-diamond powder.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.382-383
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• 2007

PMMA plate with nano-sized pattern was synthesized on anodized aluminum oxide template by bluk polymerization method. Anodized aluminum oxide was used as a template to synthesize the PMMA plate with nano-sized pattern. The polymerization of MMA was performed at $75-79^{\circ}C$. It is verified from SPM results that the nano-sized pattern on synthesized PMMA plate was well transferred from that of anodized aluminum oxide template.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.117-123
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• 2018

Recently, aqueous method has attracted lots of attention because it enables the solution-processed metal oxide thin film with high electrical properties in low temperature fabrication condition to various flexible devices. Focusing the development of aqueous route, many researchers are only focused on metal oxide materials. However, for expansive application of the aqueous-based metal oxide films, the systematic study of performance change with process variables for the development of aqueous-based metal oxide insulator film is urgently required. Here, we propose importance of process variables to achieve high electrical-performance metal oxide insulator based on the aqueous method. We found that the significant process variables including precursor solution temperature and humidity during the spincoating process strongly affect chemical, physical, and electrical properties of $AlO_x$ insulators. Through the optimization of significant variables in process, an $AlO_x$ insulator with a leakage current value approximately $10^5$ times smaller and a breakdown voltage value approximately 2-3 times greater than un-optimized $AlO_x$ was realized. Finally, by introducing the optimized $AlO_x$ insulators to solutionprocessed $InO_x$ TFTs, we successfully achieved $InO_x/AlO_x$ TFTs with remarkably high average field-effect mobility of ${\sim}52cm^2V^{-1}\;s^{-1}$ and on/off current ratio of 106 at fabrication temperature of $250^{\circ}C$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.4
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• pp.242-245
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• 2021

In this work, we fabricated oxide on an n-type silicon substrate through local anodic oxidation (LAO) using atomic force microscopy (AFM). The resulting oxide thickness was measured and its correlation with load force, scan speed and applied voltage was analyzed. The surface oxide layer was stripped using a buffered oxide etch. Ohmic contacts were created by applying silver paste on the silicon substrate back face. LAO was performed at approximately 70% humidity. The oxide thickness increased with increasing the load force, the voltage, and reducing the scan speed. We confirmed that LAO/AFM can be used to create both lateral and, to some extent, vertical shapes and patterns, as previously shown in the literature.