In- and out-of-plane dynamic flexural behaviors of two-dimensional ensembles of vertically aligned single-walled carbon nanotubes

In the present work, by considering the agglomeration effect of single-walled carbon nanotubes, free vibration characteristics of functionally graded nanocomposite sandwich sectorial plates are presented. The volume fractions of randomly oriented agglomerated single-walled carbon nanotubes are assumed to be graded in the thickness direction. To determine the effect of carbon nanotube agglomeration on the elastic properties of carbon nanotube-reinforced composites, a two-parameter micromechanical model of agglomeration is employed. In this research work, an equivalent continuum model based on the Eshelby–Mori–Tanaka approach is considered to estimate the effective constitutive law of the elastic isotropic medium (matrix) with oriented straight carbon nanotubes. The two-dimensional 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 proposed sectorial plates are simply supported at radial edges, while all possible combinations of free, simply supported, and clamped boundary conditions are applied to the other two circular edges. The benefit of using the considered power-law distribution is to illustrate and present useful results arising from symmetric and asymmetric profiles. The effects of agglomeration, geometrical, and material parameters together with the boundary conditions on the frequency parameters of the sandwich functionally graded nanocomposite plates are investigated. It is shown that the natural frequencies of structure are seriously affected by the influence of carbon nanotubes agglomeration. This study serves as a benchmark for assessing the validity of numerical methods or two-dimensional theories used to analyze the sandwich sectorial plates.

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Superior Li-Storage Performances of Liquid-Phase Exfoliated Two-Dimensional Gallium Sulfide Nanosheets/Single-Walled Carbon Nanotubes Flexible Composite

ECS Meeting Abstracts ◽

10.1149/ma2016-02/3/520 ◽

2016 ◽

Keyword(s):

Carbon Nanotubes ◽

Liquid Phase ◽

Single Walled Carbon Nanotubes ◽

Two Dimensional ◽

Single Walled Carbon ◽

Gallium Sulfide ◽

Walled Carbon Nanotubes ◽

Li Storage

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Deposition of Various Metals on Vertically-Aligned Single-Walled Carbon Nanotubes

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 2 ◽

10.1115/ht2007-32783 ◽

2007 ◽

Author(s):

Kei Ishikawa ◽

Hai Duong ◽

Junichiro Shiomi ◽

Shigeo Maruyama

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Scanning Electron Microscopy ◽

Cohesive Energy ◽

Layer Structure ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Vertically Aligned ◽

Walled Carbon Nanotubes ◽

Scanning Electron

Evaporation of different metals (Au, Ti, Al and Pd) onto Vertically-Aligned Single-Walled Carbon Nanotubes (VASWNT) has been studied. Observations through Scanning Electron Microscopy (SEM) showed a clear metal-dependence of the deposition layer structure on top of the VASWNT, reflecting the variation of wettability and cohesive energy of each metal. These characteristics also influence the structures of the metal penetrated through the top surface into VASWNT film, where metal forms particles inside VASWNT film except for Ti. A simple annealing technique to remove metals penetrated in the SWNT films is demonstrated. Some peculiar morphologies found during the processes are also presented.

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Direct Growth of Vertically-Aligned Single-Walled Carbon Nanotubes on Conducting Substrates using Ethanol for Electrochemical Capacitor

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v14i3.106 ◽

2011 ◽

Vol 14 (3) ◽

pp. 173-178 ◽

Cited By ~ 12

Author(s):

Mohd Asyadi Azam ◽

Akihiko Fujiwara ◽

Tatsuya Shimoda

Keyword(s):

Carbon Nanotubes ◽

Metal Layer ◽

Chemical Vapor ◽

Electrochemical Capacitor ◽

Single Walled Carbon Nanotubes ◽

Electrochemical Analysis ◽

Quality Level ◽

Single Walled Carbon ◽

Vertically Aligned ◽

Walled Carbon Nanotubes

A massive growth of vertically-aligned single-walled carbon nanotubes (VA-SWCNTs) from aluminum oxide (Al-O)-supported Co catalyst and high purity ethanol was performed using alcohol catalytic chemical vapor deposition (ACCVD) technique. SWCNTs with 50-μm thickness were grown on the substrates via this technique. The Al metal layer of 20 nm thickness was thermally-oxidized for the production of Al-O, and 0.5 nm cobalt (Co) thin films was used as catalyst for the CVD process. The CNT growth was optimized using SiO2/Si substrates, and similar experimental condition was applied to the conducting substrates. The as-grown CNTs were characterized using Raman spectroscopy and electron microscopies for growth confirmation and for quality level investigation. Development of the catalyst nanoparticles and Al-O support layer was observed using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The electrodes were fabricated using directly-grown VA-SWCNTs on SUS 310S, and were successfully used as an electrochemical capacitor. Electrochemical analysis using KOH aqueous electrolyte was performed by cyclic voltammetric (CV) and galvanostatic chargedischarge measurements; a maximum 52 Fg-1 specific gravimetric capacitance was obtained from the VA-SWCNT electrodes.

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