• Bulletin of the Korean Chemical Society
• /
• v.31 no.1
• /
• pp.133-139
• /
• 2010

Photoelectrocatalytic decolorization of methlene blue (MB) in the presence of two types of carbon nanotube/titania and yttrium-treated carbon nanotube/titania electrodes in aqueous solutions were studied under visible light. The prepared composite electrodes were characterized by X-ray diffraction, transmission and scanning electron microscopy, energy dispersive X-ray analysis, and photoelectrocatalytic activity. The photoelectrocatalytic performances of the supported catalysts were evaluated for the decolorization of MB solution under visible light irradiation. The results showed that yttrium incorporation enhanced the decolorization rate of MB. It was found that the photoelectrocatalytic degradation of a MB solution could be attributed to the combined effects caused by the photo-degradation of titania, the electron assistance of carbon nanotube network, the enhancement of yttrium and a function of the applied potential. The repeatability of photocatalytic activity was also tested. The presence of yttrium enhanced the hydrophillicity of yttrium-carbon nanotubes/titania electrode because more OH groups can be adsorbed on the surface.

• Carbon letters
• /
• v.23
• /
• pp.9-16
• /
• 2017

This paper introduces a nitrogen-doped ordered mesoporous carbon (NOMC) derived from glucosamine with hybrid capacitive behaviors, achieved by successfully combining electrical double-layer capacitance with pseudo-capacitance behaviors. The nitrogen doping content of the fabricated NOMC reached 7.4 at% while its specific surface area ($S_{BET}$) and total pore volume reached $778m^2g^{-1}$ and $1.17cm^3g^{-1}$, respectively. A dual mesoporous structure with small mesopores centered at 3.6 nm and large mesopores centered at 9.9 nm was observed. The specific capacitance of the reported materials reached up to $328Fg^{-1}$, which was 2.1 times higher than that of pristine CMK-3. The capacitance retention rate was found to be higher than 87.9% after 1000 charge/discharge cycles. The supplementary pseudocapacitance as well as the enhanced wettability and conductivity due to the incorporation of nitrogen heteroatoms within the carbon matrixes were found to be responsible for the excellent capacitive performance of the reported NOMC materials.

• Steel and Composite Structures
• /
• v.23 no.6
• /
• pp.657-668
• /
• 2017

In the most of previous studies, researchers have restricted their own studies to consider the effect of single walled carbon nanotubes as a reinforcement on the vibrational behavior of structures. In the present work, free vibration characteristics of functionally graded annular plates reinforced by multi-walled carbon nanotubes resting on Pasternak foundation are presented. The response of the elastic medium is formulated by the Winkler/Pasternak model. Modified Halpin-Tsai equation was used to evaluate the Young's modulus of the multi-walled carbon nanotube/epoxy composite samples by the incorporation of an orientation as well as an exponential shape factor in the equation. The exponential shape factor modifies the Halpin-Tsai equation from expressing a straight line to a nonlinear one in the multi-walled carbon nanotubes wt% range considered. The 2-D generalized differential quadrature method as an efficient and accurate numerical tool is used to discretize the equations of motion and to implement the various boundary conditions. The effects of two-parameter elastic foundation modulus, geometrical and material parameters together with the boundary conditions on the frequency parameters of the plates are investigated. This study serves as a benchmark for assessing the validity of numerical methods or two-dimensional theories used to analysis of annular plates.

• Advances in nano research
• /
• v.15 no.3
• /
• pp.253-261
• /
• 2023

This study investigates the application of nano-composite materials in physical education, specifically focusing on improving the performance of sports hall flooring. The research centers on carbon nanotube reinforced polyvinyl chloride (PVC) composites, which offer enhanced mechanical properties and durability. The incorporation of carbon nanotubes as reinforcements in the PVC matrix provides notable benefits, including increased strength, improved thermal stability, electrical conductivity, and resistance to fatigue. The key parameters examined in this study are the weight percentage of carbon nanotubes and the temperature during the fabrication process. Through careful analysis, it is found that higher weight percentages of carbon nanotubes contribute to a more uniform dispersion within the PVC matrix, resulting in improved mechanical properties. Additionally, higher fabrication temperatures aid in repairing macroscopic defects, leading to enhanced overall performance. The findings of this study indicate that the utilization of carbon nanotube reinforced PVC composites can significantly enhance the strength and durability of sports hall flooring. By employing these advanced materials, the safety and suitability of physical education environments can be greatly improved. Furthermore, the insights gained from this research can contribute to the optimization of composite material design and fabrication techniques, not only in the field of physical education but also in various industries where composite materials find applications.

• Corrosion Science and Technology
• /
• v.4 no.6
• /
• pp.226-230
• /
• 2005

Si incorporated diamond-like carbon (Si-DLC) films ranging from 0 to 2 at.% contents were deposited on STS 316L substrates for orthopedic implants by means of r.f. plasma-assisted chemical vapor deposition (r.f. PACVD) technique, using mixtures of benzene ($C_6H_6$) and silane ($SiH_4$) as the precursor gases. This study provides the reliable and quantitative data for assessment of the effect of Si incorporation on corrosion property in the simulated body fluid environment through the electrochemical test. It was found that corrosion to resistance of Si-DLC coatings with increasing Si content are improved owing to high $sp^3$ bonding.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.402-402
• /
• 2012

Bundles of single-walled carbon nanotube (SWCNTs) were grown using catalytic layer supported by self-assembled monolayers (SAMs). Amine-SAMs were introduced on SiO2/Si substrate (SAMs/Si) there then iron nanoclusters solution was dropped on it through spin-coating (Fe/SAMs/Si). This catalytic template was used to grow CNTs and the synthesized carbon material was confirmed the bundles of dense SWCNTs with incorporation of ca.1% nitrogen. The SAMs has played an active role to support catalytic layer and also acted as a source of N-dope onto SWCNTs in CVD.

• Journal of Sensor Science and Technology
• /
• v.9 no.3
• /
• pp.248-255
• /
• 2000

Penning type sputtering system which has two opposed targets was implemented and the physical characteristics of the deposited carbon nitride films were investigated. When argon ratio was reduced and nitrogen ratio was increased in the sputtering gas mixture, Fe was less sputtered. The grain size of grown carbon nitride films was distributed from $150{\AA}$ to $250{\AA}$. As nitrogen partial pressure increases, growth rate and nitrogen incorporation in the film increases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.31 no.2
• /
• pp.94-97
• /
• 2018

Lead zirconate titanate/poly-vinylidene fluoride (PZT/PVDF) piezoelectric devices were fabricated by incorporating carbon nanotubes (CNTs), for use as flexible energy harvesting devices. CNTs were added to maximize the formation of the ${\beta}$ phase of PVDF to enhance the piezoelectricity of the devices. The phase transition of PVDF induced by the addition of CNTs was confirmed by analyzing the X-ray diffraction patterns, scanning electron microscopy images, and atomic force microscopy images. The enhanced output efficiency of the PZT/PVDF piezoelectric devices was confirmed by measuring the output current and voltage of the fabricated devices. The maximum output current and voltage of the PZT/PVDF piezoelectric devices was 200 nA and 350 mV, respectively, upon incorporation of 0.06 wt% CNTs.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.10
• /
• pp.1501-1504
• /
• 2003

Single-wall carbon nanotubes (SWCN) were integrated in $TiO_2$ film and the beneficial influence on the dyesensitized solar cells in terms of improved photocurrent was studied in the light of static J-V characteristics obtained both under illumination and in the dark, photocurrent transients, IPCE spectra and impedance spectra. Compared with a solar cell without SWCN, it is established that the photocurrent density of the modified cell increases at all applied potentials. The enhanced photocurrent density is correlated with the augmented concentration of electrons in the conduction band of $TiO_2$ and with increased electrical conductivity. Explanations are additionally corroborated with the help of SEM, Raman spectra and dye-desorption measurements.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2011.05a
• /
• pp.59-60
• /
• 2011

The purpose of this study is to produce the low-carbon eco-friendly inorganic composite at room temperature by an alkali accelerator without firing process at high temperature, and complement the problem of previous studies, the deterioration in strength caused by cracking, with incorporation of PVA fibers. Results of reviewing the changes in the strength properties of PVA showed that test body mixed with PVA fibers had the superiority in strength expression.