• Journal of the Korean Society for Heat Treatment
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• v.22 no.1
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• pp.23-26
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• 2009

Pt nanotubes with diameter of 200 nm were fabricated by simple and convenient method of Template-Wetting Process. Porous alumina membranes were prepared by 2 step anodic oxidation as the template. To improve wetting properties and lower surface energy, pt solution was mixed with polymer. Polymer was removed completely during annealing. Grain growth process of pt nanotubes during baking and furnace annealing was examined by FE-SEM and XRD.

• Journal of the Korean Ceramic Society
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• v.44 no.5 s.300
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• pp.141-143
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• 2007

Nanotubes and microtubes of ferroelectric lead zirconate titanate (PZT) were synthesized by means of a simple and convenient process called a template-wetting process. Nanoporous alumina and macroporous Si were used as template materials to fabricate the corresponding tubes. For the improvement of the wetting properties of the wetting solution, the PZT solution was mixed with a polymer. The polymer was removed completely during annealing. The grain growth processes of the PZT nanotubes during baking and furnace annealing were examined by means of field emission electron microscope (FE-SEM) and X-ray diffractometry (XRD).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.83-83
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• 2005

• Journal of the Korean Ceramic Society
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• v.43 no.4 s.287
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• pp.220-223
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• 2006

BLT nanotubes were synthesized by using simple and convenient method template-wetting process. Porous alumina membranes were prepared by 2 step anodic oxidation as the template. To improve wetting properties and make low surface energy, BLT solution was mixed with polymer. Polymer was removed completely during annealing. After completely etching the template in 30 wt% KOH solution, we demonstrate that BLT nanotubes with a diameter of 200 nm can be fabricated. Grain growth process of BLT nanotubes during baking, and furnace annealing was examined by FE-SEM and XRD.

• Clean Technology
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• v.18 no.3
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• pp.295-300
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• 2012

Synthesis of well-defined particle with tunable size, shape, and functionalities is strongly emphasized for various applications such as chemistry, biology, material science, chemical engineering, medicine, and biotechnology. This study presents micromolding method for the fabrication of anisotropic particles with elegant control of curvature of covex roof. For the demostration of rapid fabrication of the particles, we have applied polydimethylsiloxane (PDMS) micromold as structure guiding template and wetting fluid to control curvature of roof of the particles. Based on this approach, we can control the radius of curvature from $20{\mu}m$ to $70{\mu}m$ with different aspect ratio of mold. In addition, wetting fluids with different wetting properties can also modulate the height and radius of curvature of the particles. We envision that this methodology is promising tool for precise control of particle shape in 3-dimensional space and new synthetic route for anisotropic particles with cost effective, simple, easy, and fast procedure.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.31-32
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• 2006

We describe the preparation of nanostructured molecularly-imprinted surfaces using nanomolding on porous alumina. In molecular imprinting functional and cross-linking monomers are copolymerized in the presence of a molecular template, resulting in synthetic receptor materials. The drug propranolol and the dye fluorescein were used as the molecular imprinting templates. Binding studies with imprinted and non-imprinted surfaces revealed specific recognition of the templates and thus the existence of selective binding sites. In addition, the surface properties of the films were studied by water contact angle measurements. It was found that, depending on the monomers used, certain nanostructures induced great changes in the wetting properties of the surface.

• Journal of the Korean Ceramic Society
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• v.51 no.6
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• pp.539-543
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• 2014

Foam type porous silicon carbide ceramics were fabricated by a polymer replica method using polyurethane foam, carbon black, phenol resin, and silicon powder as raw materials. The influence of the C/Si mole ratio of the ceramic slurry and heat treatment temperature on the porous silicon carbide microstructure was investigated. To characterize the microstructure of porous silicon carbide ceramics, BET, bulk density, X-ray Powder Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were employed. The results revealed that the surface area of the porous silicon carbide ceramics decreases with increased heat treatment temperature and carbon content at the $2^{nd}$ heat treatment stage. The addition of carbon to the ceramic slurry, which was composed of phenol resin and silicon powder, enhanced the direct carbonization reaction of silicon. This is ascribed to a consequent decrease of the wetting angles of carbon to silicon with increasing heat treatment temperature.

• Tribology and Lubricants
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• v.35 no.2
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• pp.94-98
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• 2019

The riblet structure like shark skin has been widely studied owing to its drag reduction and anti-fouling properties. In this study we simulated the wettability of an oil droplet on a riblet surface. We developed a numerical analysis method using the Wenzel equation and Cassie-Baxter equation that can estimate the contact angle with a penetrated depth of the droplet on rough surfaces. Riblet surfaces with nine scales composed of five hemi-elliptical ribs are generated numerically. The variation of contact angles with fractional depth of penetration for the generated riblet surfaces with and without coatings is demonstrated in the condition of solid-air-oil and solid-water-oil interfaces. The contact angle for the uncoated surface decreases with increasing fractional depth of penetration more drastically than that for the coated surface. For the effect of surface roughness on the contact angle of the droplet, the oleophilic surface gives lower contact angle when the surface is rougher, whereas the oleoophobic surface gives higher contact angle with higher roughness To verify the analysis results, the wetting angle was measured in the solid-air-oil interface and solid-water-oil interface for the shark-skin template and shark-skin replica. The effects of teflon coating were also evaluated. It is shown that the simulation results cover the experimental ones.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.205-208
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• 2014

Here, we reported mass-produced organic nanowires with uniform sizes based on poly(9,9-dioctylflurorene) (PFO), poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT), (regioregular poly(3-hexylthiophene) (P3HT) which are well known as organic semiconductors for opto/electronics applications, using a melt-assisted wetting method with anodic alumina membrane. The conjugated polymer nanowires showed uniformed diameters (D=250~300 nm) and lengths ($L={\sim}30{\mu}m$) with defect free smooth surface regardless of a kinds of semiconductors. In addition, the nanowires were uniformly deposited onto glass substrates by spray-coating method. Under the UV light irradiation, PFO and F8BT nanowires showed blue and yellow emissions, respectively.