• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08b
• /
• pp.1257-1260
• /
• 2007

A single-wall carbon nanotube (SWNT) transparent conductive film (TCF) was fabricated using a simple inkjet printing method. The TCF could be selectively patterned by controlling the dot size to diameters as small as $34\;{\mu}m$. In this repeatable and scalable process, we achieved 71% film transmittance and a resistance of 900 ohm/sq sheet with an excellent uniformity, about ${\pm}\;5%$ deviation overall. Inkjet printing of SWNT is substrate friendly and the TCF is printed on a flexible substrate. This method of fabrication using direct printing permits mass production of TCF in a large area process, reducing processing steps and yielding low-cost TCF fabrications on a designated area using simple printing.

• Fibers and Polymers
• /
• v.6 no.2
• /
• pp.108-112
• /
• 2005

Nanocomposite films were prepared by casting the solution of polyacrylonitrile (PAN) and single wall nanotube (SWNT) in nitric acid subsequent to sonication. Even though SWNT shows good dispersion visually, the reinforcing effect was not satisfactory. The G-band Raman spectra of the drawn film clearly demonstrated that SWNTs in the film are well-oriented along the drawing axis of the film. The electrical resistivity of the film prepared using nitric acid was lower than that of the film using DMF. Thus, nitric acid is presumably more effective in dispersing nanotubes than DMF.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.1047-1052
• /
• 2003

Controlling carrier transport in light emitting polymers is extremely important for their efficient use in organic opto-electronic devices [1]. Here we show that the interactions between single wall carbon nanotubes (SWNTs) and conjugated polymers can be used to modify the overall mobility of charge carriers within nanotube-polymer nanocomposites. By using a unique, double emitting-organic light emitting diodes (DE-OLEDs) structure. we have characterized the hole transport within electroluminescent nanocomposites (nanotubes in poly (m-phenylene vinylene-co-2,5-dioctoxy-p-phenylene) or PmPV). We have shown using this idea that single devices with color tunability can be fabricated. It is seen that SWNTs in PmPV are responsible for hole trapping, leading to shifts in the emission wavelengths. Our results could lead to improved organic optical amplifiers, semiconducting devices, and displays.

• Korean Journal of Materials Research
• /
• v.18 no.10
• /
• pp.529-534
• /
• 2008

The hydrogen gas sensing properties of a zinc oxide nanowire structure were studied. Porous zinc oxide nanowire structures were fabricated by oxidizing zinc deposited on a single-wall carbon nanotube (SWNT) template. This revealed a porous ZnO-SWNT composite due to the porosity in the SWNT film. The gas sensing properties were compared with those of zinc oxide thin films deposited on SiO2/Si substrates in sensitivity and operating temperature. The composite structure showed higher sensitivity and lower operating temperature than the zinc oxide film. It showed a response even at room temperature while the film structure did not.

• Elastomers and Composites
• /
• v.49 no.3
• /
• pp.204-209
• /
• 2014

Sodium-montmorillonite ($Na^+$-MMT) was introduced into single wall carbon nanotube (SWCNT)/epoxy composite to investigate the effect of MMT size and MMT/SWCNT ratio on the mechanical and electrical properties of composite. Three different sizes of MMTs were used and all were found to function as effective dispersion aids for SWCNTs. Mechanical properties of SWCNT/epoxy composite increased with MMT content; tending to decrease once the MMT content reached a critical level. However, the surface electrical resistance decreased with increasing MMT content and tended to increase after the critical content was reached. Critical MMT/SWCNT ratio for maximum mechanical properties and minimum electrical resistivity was strongly dependent on the MMT size. Critical MMT/SWCNT ratio was decreased with MMT size.

• Fibers and Polymers
• /
• v.5 no.3
• /
• pp.198-203
• /
• 2004

Composite films were prepared by casting the solution of polyacrylonitrile (PAN) and single wall nanotube (SWNT) in DMF subsequent to sonication. The SWNTs in the films are well dispersed as ropes with 20-30 nm thickness. Moreover, AFM surface image of the composite film displays an interwoven fibrous structure of nanotubes which may give rise to conductive passways and lead to high conductivity. The polarized Raman spectroscopy is an ideal characterization technique for identification and the orientation study of SWNT. The well-defined G-peak intensity at 1580 $cm^{-1}$shows a dependency on the draw ratio under cross-Nicol. The degree of nanotube orientation in the drawn film was measurable from the sine curve obtained by rotating the drawn film on the plane of cross-Nicol of polarized Raman microscope. The threshold loading of SWNT for electrical conductivity in PAN is found to be lower than 1 wt% in the composite film. The electrical conductivity of the SWNT/PAN composite film decreased with increasing of draw ratio due to the collapse of the interwoven fibrous network of the nanotubes with uniaxial orientation.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.1233-1234
• /
• 2006

A simple new method to fabricate transparent carbon nanotube field emission devices was developed. The highly graphitized single wall carbon nanotubes were attached on Sn/ITO glass by arc discharge method. Post heat treatments below the deformation temperature of soda-lime glass guaranteed a good mechanical adhesion and electrical contact of the nanotubes. The Sn layer was oxidized below $400^{\circ}C$ and became transparent. As increasing the oxidation temperatures, the emission properties became stable and life time of emitter has been increased.

• Advances in Computational Design
• /
• v.8 no.1
• /
• pp.77-96
• /
• 2023

Calculating size-dependent mechanical properties of the nano-scale materials usually involves cumbersome numerical and theoretical works. In this paper, we aim to present a closed-form relation to calculate the length-dependent Young's modulus of carbon nanotubes (CNTs) based on nonlocal elasticity theory. In this regard, a single wall carbon nanotube (SWCNT) is considered as a rod structure and the governing nonlocal equations are developed under uniaxial tensile load. The equations are solved using analytical methods and strain distribution, total displacement and the size-dependent equivalent Young's modulus are obtained. Further, the results are compared with the molecular dynamics results from the literature. The outcome indicates that the calculated relations are coincident with the molecular dynamics results.

• Korean Journal of Materials Research
• /
• v.18 no.5
• /
• pp.277-282
• /
• 2008

The effects of the field emission property in relation to the surface morphology and adhesion force were investigated. The single-wall-nanotube-based cathode was obtained by use of an in-situ arc discharge synthesis method, a screen-printing method and a spray method. The morphologies of the formed emitter layers were very different. The emission stability and uniformity were dramatically improved by employing an in-situ arc discharge synthesis method. In this study, it was confirmed that the current stability and uniformity of the field emission of the cathode depend on the surface morphology and adhesion force of the emitters. The current stability of the field emission device was also studied through an electrical aging process by varying the current and electric field.

• 한국전기화학회:학술대회논문집
• /
• 2003.07a
• /
• pp.183-187
• /
• 2003

Carbon nanotubes, prepared by the catalytic decomposition of acetylene at $700^{\circ}C$ over a Mm based $AB_5$ hydrogen storage alloy hydride catalysts, have been used as a support for platinum electrocatalysts. The performance of this electrocatalyst In proton exchange membrane fuel cells has been studied and discussed.