Growth of Single-Walled Carbon Nanotubes by Disproportionation of CO Over Co-Re/SiO2 Catalysts

2007 ◽  
Vol 121-123 ◽  
pp. 337-342
Author(s):  
P. Chungchamroenkit ◽  
B. Kitiyanan ◽  
Jose E. Herrera ◽  
Sumaeth Chavadej ◽  
D.E. Resasco
Keyword(s):  
Carbon Nanotubes ◽  
Single Walled Carbon Nanotubes ◽  
Molar Ratio ◽  
Rhenium Oxide ◽  
Temperature Programmed Oxidation ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Temperature Programmed ◽  
Walled Carbon Nanotubes

A series of silica supported Co-Re catalysts was prepared and used as catalysts for the synthesis of single-walled carbon nanotubes (SWNT) by carbon monoxide disproportionation at 750 – 950 °C. The characterization of catalysts suggests that good quality of SWNT was obtained from partially reduced and completely reduced cobalt-rhenium oxide. The carbon products were characterized by Raman spectroscopy, temperature programmed oxidation (TPO) and transmission electron microscope (TEM). The effects of reaction parameters such as molar ratio of Co to Re, reduction temperature, and reaction temperature were investigated. It was found the the synergism of Co and Re in the catalytic production of SWNT leads to high selectivity of SWNT.

Purification and Characterization of Single-Walled Carbon Nanotubes

1999 ◽  
Vol 593 ◽  
Author(s):  
H.Y. Kim ◽  
W.B. Choi ◽  
N.S. Lee ◽  
D.S. Chung ◽  
J.H. Kang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Sulfuric Acid ◽  
Volume Ratio ◽  
Single Walled Carbon Nanotubes ◽  
Tem Analysis ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Walled Carbon Nanotubes

ABSTRACTSingle-walled carbon nanotubes (SWNTs) were purified and cut into short length by the liquid phase oxidation using the typical oxidants such as HNO3, H2SO4 and their mixture. The SWNTacid solutions were refluxed at high temperature, filtered on poly tetra-fluoro ethylene (PTFE) filter paper. rinsed with distilled water, and then dried at room temperature. In order to find optimum purifying condition, acid solutions were made by mixing nitric / sulfuric acid by the different volume ratio. The reaction time was also varied from 1h to 6h. Through this method, purified SWNTs with the length of less than 2μm were successfully obtained, which was confirmed by scanning electron microscopy (SEM). From transmission electron microscopy (TEM) analysis, it was verified that SWNTs were purified with little damage on surface and metal catalysts were efficiently removed when sulfuric acid was mixed, which was also confirmed by energy disperse spectrum analysis (EDS). Moreover, size distribution of the purified SWNTs was characterized with Field Flow-Fractionation (FFF) method.

Metal Coated Functionalized Single-Walled Carbon Nanotubes for Composites Application

2007 ◽  
Vol 561-565 ◽  
pp. 655-658 ◽  
Author(s):  
Qiang Zeng ◽  
Jennifer Luna ◽  
Y. Bayazitoglu ◽  
Kenneth Wilson ◽  
M. Ashraf Imam ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Single Walled Carbon Nanotubes ◽  
Metal Composite ◽  
X Ray ◽  
Single Walled Carbon ◽  
Transmission Electron ◽  
Nucleation Sites ◽  
Metal Composite Materials ◽  
Walled Carbon Nanotubes

This study is considered as a method for producing multifunctional metal composite materials by using Single-walled Carbon Nanotubes (SWNTs). In this research, various metals (Ni, Cu, Ag ) were successfully deposited onto the surface of SWNTs. It has been found that homogenous dispersion and dense nucleation sites are the necessary conditions to form uniform coating on SWNTs. Functionalization has been applied to achieve considerable improvement in the dispersion of purified single-walled carbon nanotubes. A three-step electroless plating approach was used and the coating mechanism is described in the paper. The samples were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDX). The application of coated SWNTs in Titanium will be discussed in this paper.

Image Restoration of One-Dimensional HgTe Crystals Formed within Single Walled Carbon Nanotubes

2006 ◽  
Vol 514-516 ◽  
pp. 1131-1134
Author(s):  
Jeremy Sloan ◽  
Robin Carter ◽  
Angus I. Kirkland ◽  
Rüdiger R. Meyer ◽  
Alexis Vlandas ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Three Dimensional ◽  
Single Walled Carbon Nanotubes ◽  
One Dimensional ◽  
Single Walled Carbon ◽  
Semiconductor Crystals ◽  
Transmission Electron ◽  
Walled Carbon Nanotubes ◽  
Separate Crystal

Restored high resolution transmission electron microscopy (HRTEM) images have been recorded from 1D semiconductor crystals formed within narrow diameter (ca. 1.4 nm) single walled carbon nanotubes (SWNTs). Two unique projections were obtained from separate crystal fragments encapsulated within separate nanotubes that has facilitated the reconstruction of the three dimensional arrangement of atoms within the two encapsulated fragments.

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