• Journal of the Korean Ceramic Society
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• v.46 no.6
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• pp.648-652
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• 2009

Ceramic fiber separator is the promising material for thermal battery system because it reduces the production cost and offers the potential to a new application compared to a pellet type electrolyte. The electrolyte separator for thermal battery should be easily handled and loaded a large amount of the molten lithium salt. Ceramic fibers were used as an electrolyte separator and the lithium based molten salts were infiltrated into the ceramic filters. Leakage of molten salt (several lithium salts) leads to short-circuit during the thermal battery operation. In this study, a uniform and fine SiOC mat with fibers ranging from 1 to 3 ${\mu}m$ was obtained by electrospinning of polycarbosilane and pyrolysis. The optimum spinning conditions for obtaining fine diameters of SiOC fiber were controlled by the solution composition and concentration, applied voltage and spinning rate, release rate by porosity. The pore structures of the ceramic filter and the melting properties of the lithium salts affected to the electrolyte loading and leakage. The importance of the fiber size and porosity and their control was discussed and the mechanical properties were also discussed.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.171-172
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• 2003

Electrically conducting polymers have attracted a great deal of attention because of their unusual electronic Properties.1 One of them, polypyrrole has been widely studieddue to its high conductivity and good environmental stability. 2Especially polypyrrole nano-Particles and -fibers are interesting because of their unique properties and applications. Recently amorphous polypyrrole nano-particles were fabricated using microemulsion Polymerization at low temperature. (omitted)

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.102-102
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• 2010

One or two-dimensional nanostructures such as nanowires or nanomats have been widely uses as building blocks for nanoscale electronic devices. Nanofiber is one of sub-category of nano structures, it is easy to make nano-sized fiber by electrospinning technique. Nanofiber has large surface area as compared with their volume, it could be widely applied to many areas easily. Electrospinning technique is easy to control their structures and morphology safely and cost-effectively. We made nano-rings as a model of one dimensional nanostructures by electrospinning technique. To our knowledge, there were no reports on the preparation and investigation of alumina nano-rings by electrospinning technique. In this study, aluminum oxide nano-rings were produced after electospinning and calcination. The synthesized aluminum oxide nano-rings were characterized by scanning electron microscopy (SEM) to identify the morphology and the diameter of the ring, X-ray diffraction (XRD) to verify the crystallinity of the aluminum oxide, and X-ray photoelectron spectroscopy (XPS) for investigation of the chemical nature of the synthesized nano-rings.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.304-307
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• 2012

Nano-fibers of LiFePO4 were synthesized from a metal oxide precursor by adopting electrospinning method. After calcination of the above precursor nano-fibers at 800 ℃, LiFePO4 nano-fibers with a diameter of 300 ~ 800 nm, were successfully obtained. Measurement were performed using X-ray diffraction (XRD), fourier transform infrared spectrometer (FT-IR), videoscope, scanning electron microscope (SEM) and atomic force microscope (AFM), respectively, were performed to characterize the properties of the as-prepared materials. The results showed that the crystalline phase and morphology of the fibers were largely influenced the starting materials and electrospinning conditions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.4
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• pp.158-163
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• 2014

Mineral fiber, or be called mineral wool when it assembles in large amounts, is a kind of wide applied man-made material with excellent thermal and acoustic insulation properties. In this work, mineral fiber was produced via melt spinning method by using iron blast furnace slag as raw material. Two critical experimental parameters for fabrication were investigated: melt pouring temperature and rotating speed of spinning wheels. The mineral fiber produced under the condition of melt pouring temperature $1500^{\circ}C$ and spinning speed 4000 rpm, showed the smoother surface and most quality, while the others had rough surfaces or with heavy shots. In general, mineral fibers with the size in the range of $12{\sim}49{\mu}m$ in diameter and 8~130 mm in length can be fabricated by this method, and the production rate is more than 34 wt.%, which could be up to 57 wt.% at maximum.

• Rapid Communication in Photoscience
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• v.2 no.2
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• pp.46-51
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• 2013

This study reports a fiber-optic sensor detecting biomolecule by simultaneously monitoring localized surface plasmon resonance (LSPR) from gold nanoparticles (Au NPs) of ca. $50{\pm}5$ nm attached on one end of optical fiber and surface enhanced Raman scattering (SERS) of the reporter molecules adsorbed on the gold surfaces as an additional sensing tool. The sensor was fabricated by immobilizing Au NPs on one end of an optical fiber by chemical reaction. LSPR and SERS signals of the sensor were measured using various refractive indices solutions. Finally, the sensor was applied to observe real-time LSPR sensor-gram and SERS spectra of the reporter molecule of 4-aminothiphenol during the antibody-antigen reaction of interferon-gamma (IFN-${\gamma}$) as a proof-concept experiment of biological applications.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.11
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• pp.1297-1308
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• 2011

This research investigates the application of ZnO (zinc oxide) nanoparticles and $TiO_2$ (titanium dioxide) nanoparticles to polypropylene nonwoven fabrics via an electrospinning technique for the development of textile materials that can decompose harmful gases. To fabricate uniform ZnO nanocomposite fibers, two types of ZnO nanoparticles were applied. Colloidal $TiO_2$ nanoparticles were chosen to fabricate $TiO_2$ nano- composite fibers. ZnO/poly(vinyl alcohol) (PVA) and $TiO_2$/PVA nanocomposite fibers were electrospun under a variety of conditions that include various feed rates, electric voltages, and capillary diameters. The morphology of electrospun nanocomposite fibers was examined with a field-emission scanning electron micro- scope and a transmission electron microscope. Decomposition efficiency of gaseous materials (formaldehyde, ammonia, toluene, benzene, nitrogen dioxide, sulfur dioxide) by nanocomposite fiber webs with 3wt% nano-particles (ZnO or $TiO_2$) and 7$g/m^2$ web area density was assessed. This study shows that ZnO nanoparticles in colloid were more suitable for fabricating nanocomposite fibers in which nanoparticles are evenly dispersed than in powder. A heat treatment was applied to water-soluble PVA nanofiber webs in order to stabilize the electrospun nanocomposite fibrous structure against dissolution in water. ZnO/PVA and $TiO_2$/PVA nanofiber webs exhibited a range of degradation efficiency for different types of gases. For nitrogen dioxide, the degradation efficiency was 92.2% for ZnO nanocomposite fiber web and 87% for $TiO_2$ nanocomposite fiber web after 20 hours of UV light irradiation. The results indicate that ZnO/PVA and $TiO_2$/PVA nano- composite fiber webs have possible uses in functional textiles that can decompose harmful gases.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.154-157
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• 2003

Precision displacement of less than a few nm resolution was measured in real-time using fiber optic EFPI sensor. The novel method for real-time processing of analyzing EFPI output signal was developed and verified. Linearity in the mean values of interferometric light intensity among adjacent fringes was shown, and the sinusoidal approximation algorithm that estimates past and coming fringe values was verified through the linearity. Real-time signal processing program was developed, and the intensity signal of the EFPI sensor was transformed to the phase shift with this program. The resolution below 0.4 ~ 10 nm in the displacement range of $0 ~ 300\mu\textrm{m}$ was obtained by reducing the photodetector noise using low-pass filter and signal averaging. The nano-translation stage with a Piezo-electric actuator and the EFPI sensor system was designed and tested. This stage successfully reached to the desired destination in $15\mu\textrm{m}$ range within 1 nm accuracy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1058-1061
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• 2004

미세 소자를 관측, 가공 및 분석하기 위해 사용되는 기존 광학현미경은 빛으로 물체를 관측하므로 대물렌즈 (Object lens)에서의 회절한계 때문에 분해능의 있으므로 매우 뽀족한 탐침(Probe)을 시료의 표면에 근접시킨 후 표면을 주사하여 이미지를 얻는 방법이 개발되어 최근에는 Optical Fiber를 이용하여 fiber 끝단을 nano-scale 정도로 첨예화시키는 기술이 개발되었다. 이러한 광섬유 탐침은 구경의 직경이 작을수록 높은 분해능을 얻을 수 있으므로 광섬유 탐침의 제작 공정 확립은 매우 중요하다. 그 중에서 대표적인 방법이 $CO_2$ 레이저를 이용하여 가열한 후 인장 하는 방법 (Heating and Pulling)이 있다. 그래서 본 연구에서는 $CO_2$ 레이저를 이용하여 100nm 정도의 팁 반경을 갖는 뽀족한 탐침을 제작하고자 한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.141-142
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• 2009