• Transactions on Electrical and Electronic Materials
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• v.13 no.4
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• pp.165-170
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• 2012

One-dimensional, nanomaterial field effect transistors (FET) are promising sensors for bio-molecule detection applications. In this paper, we review fabrication and characteristics of 1-D nanomaterial FET type biosensors. Materials such as single wall carbon nanotubes, Si nanowires, metal oxide nanowires and nanotubes, and conducting polymer nanowires have been widely investigated for biosensors, because of their high sensitivity to bio-substances, with some capable of detecting a single biomolecule. In particular, we focus on three important aspects of biosensors: alignment of nanomaterials for biosensors, surface modification of the nanostructures, and electrical detection mechanism of the 1-D nanomaterial sensors.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.120.2-120.2
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• 2007

• Journal of Powder Materials
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• v.21 no.5
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• pp.360-365
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• 2014

$SnO_2-CoO$/carbon-coated CoO core/shell nanowire composites were synthesized by using electrospinning and hydrothermal methods. In order to obtain $SnO_2-CoO$/carbon-coated CoO core/shell nanowire composites, $SnO_2-Co_3O_4$ nanowire composites and $SnO_2-Co_3O_4$/polygonal $Co_3O_4$ core/shell nanowire composites are also synthesized. To demonstrate their structural, chemical bonding, and morphological properties, field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were carried out. These results indicated that the morphologies and structures of the samples were changed from $SnO_2-Co_3O_4$ nanowires having cylindrical structures to $SnO_2-Co_3O_4/Co_3O_4$ core/shell nanowires having polygonal structures after a hydrothermal process. At last, $SnO_2-CoO$/carbon-coated CoO core/shell nanowire composites having irregular and high surface area are formed after carbon coating using a polypyrrole (PPy). Also, there occur phases transformation of cobalt phases from $Co_3O_4$ to CoO during carbon coating using a PPy under a argon atmosphere.

• Advances in nano research
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• v.9 no.1
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• pp.25-32
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• 2020

In this work, we report the use of caffeine as an alternative source of nitrogen to successfully dope graphene (quaternary 400.6 eV and pyridinic at 398 eV according XPS), as well as the growth of silver nanowires (in-situ) in the surface of nitrogen doped graphene (NG) sheets. We used the improved graphene oxide method (IGO), chemical reduction of graphene oxide (GOx), and impregnation with caffeine as source of nitrogen for doping and subsequently, silver nanowires (NW) grow in the surface by the reduction of silver salts in the presence of NG, achieving a numerous of growth of NW in the graphene sheets. As supporting experimental evidence, the samples were analyzed using conventional characterization techniques: SEM-EDX, XRD, FT-IR, micro RAMAN, TEM, and XPS.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.1028-1031
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• 2002

Ga-based semiconductor nanowires (GaN, GaP) were synthesized by the reaction of Ga metal and GaN/GaP powder with a $NH_3/Ar$ gas using thermal chemical vapor deposition. The field emission and emission stability under oxygen and argon environments were investigated. Field emission energy distributions of electrons from these nanowires revealed that field emission mechanism of the semiconductor nanowires were different from carbon nanotubes.

• Journal of the Korean Vacuum Society
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• v.15 no.5
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• pp.499-505
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• 2006

Field emission of GaN and GaP nanowires, synthesized by thermal chemical vapor deposition, and their emission stabilities under oxygen and argon environments were investigated. The field emission current of GaN nanowires was seriously deteriorated under oxygen environment, while that of GaP was not. Both wires did not show any noticeable change under argon environment. The existence of oxide outer shell layers in the GaP nanowires was proposed to be a main reason for this emission stability behavior. Field emission energy distributions of electrons from these nanowires revealed that field emission mechanism of the semiconductor nanowires were different from that of carbon nanotubes.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.456-462
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• 2023

An electrically conductive and transparent electrode was created by applying a dispersion of pristine single-walled carbon nanotubes (SWCNTs) and silver nanowires to a polyethylene terephthalate (PET) film using a bar coating method. The SWCNTs were added to increase the electrical conductivity and transmittance of the silver nanowires while also preventing the haze from increasing due to the stacking of multiple layers containing SWCNTs and silver nanowires on the PET substrate. The silver nanowires in the electrode were also found to be stable against oxidation. The transparent electrode displayed excellent electrical and optical properties, with a sheet resistance of 47 Ω/□, transmittance of 96.72%, and haze of 1.93%. Additionally, the sheet resistance of the electrode remained stable over time, with a change of only 6.4% after a constant temperature and humidity test, making it suitable for long-term use. A hybrid transparent electrode that is economically feasible and environmentally sustainable has been developed through the utilization of pristine SWCNT and silver nanowire.

• Korean Journal of Materials Research
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• v.20 no.12
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• pp.686-690
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• 2010

$TiO_2$ nanowires were self-catalytically synthesized on bare Si(100) substrates using metallorganic chemical vapor deposition. The nanowire formation was critically affected by growth temperature. The $TiO_2$ nanowires were grown at a high density on Si(100) at $510^{\circ}C$, which is near the complete decomposition temperature ($527^{\circ}C$) of the Ti precursor $(Ti(O-iPr)_2(dpm)_2)$. At $470^{\circ}C$, only very thin (< $0.1{\mu}m$) $TiO_2$ film was formed because the Ti precursor was not completely decomposed. When growth temperature was increased to $550^{\circ}C$ and $670^{\circ}C$, the nanowire formation was also significantly suppressed. A vaporsolid (V-S) growth mechanism excluding a liquid phase appeared to control the nanowire formation. The $TiO_2$ nanowire growth seemed to be activated by carbon, which was supplied by decomposition of the Ti precursor. The $TiO_2$ nanowire density was increased with increased growth pressure in the range of 1.2 to 10 torr. In addition, the nanowire formation was enhanced by using Au and Pt catalysts, which seem to act as catalysts for oxidation. The nanowires consisted of well-aligned ~20-30 nm size rutile and anatase nanocrystallines. This MOCVD synthesis technique is unique and efficient to self-catalytically grow $TiO_2$ nanowires, which hold significant promise for various photocatalysis and solar cell applications.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.5
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• pp.497-497
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• 2015

• Korean Journal of Materials Research
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• v.33 no.7
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• pp.279-284
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• 2023

One-dimensional MgO nanostructures with various morphologies were synthesized by a thermal evaporation method. The synthesis process was carried out in air at atmospheric pressure, which made the process very simple. A mixed powder of magnesium and active carbon was used as the source powder. The morphologies of the MgO nanostructures were changed by varying the growth temperature. When the growth temperature was 700 ℃, untapered nanowires with smooth surfaces were grown. As the temperature increased to 850 ℃, 1,000 ℃ and 1,100 ℃, tapered nanobelts, tapered nanowires and then knotted nanowires were sequentially observed. X-ray diffraction analysis revealed that the MgO nanostructures had a cubic crystallographic structure. Energy dispersive X-ray analysis showed that the nanostructures were composed of Mg and O elements, indicating high purity MgO nanostructures. Fourier transform infrared spectra peaks showed the characteristic absorption of MgO. No catalyst particles were observed at the tips of the one-dimensional nanostructures, which suggested that the one-dimensional nanostructures were grown in a vapor-solid growth mechanism.