Growth behavior and structures of carbon nanotubes

1993 ◽  
Vol 51 ◽  
pp. 752-753
Author(s):  
Mingqi Liu ◽  
John M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Arc Discharge ◽  
The Novel ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Potential Applications ◽  
Discharge Method

Recent discovery of the novel hollow graphitic tubules of nanometer dimensions, so called carbon nanotubes, has greatly stimulated the studies in the field of carbon fiber growth. Their potential applications in electronic and materials industries have been suggested. In the present study, carbon nanotubes were fabricated by an arc-discharge method. The microstructures of nanotubes thus obtained were examined with a JEM-2000FX high-resolution transmission electron microscopy (HRTEM) and with an electron nanodiffraction technique in a VG HB-5 scanning transmission electron microscopy (STEM).HRTEM images show that nanotubes, consisting of 3 to 30 carbon sheets, have a length up to 1 μm and a diameter of 6 to 26 nm. Some nanotubes have a symmetric uniform sheet spacing of 0.34 nm. Others show non-symmetric uneven fringes (Fig. 1), indicating that they may have a polyhedral cross section. Most nanotubes are closed by cone-like or polyhedral shaped caps (Figs. 2 and 3). The closure angle varies from 17 to 40° and the internal sheets have a tendency to be closed in pairs. Fig. 4 shows the image of a growing tubes.

scholarly journals Filling Single Wall Carbon Nanotubes with Metal Chloride and Metal Nanowires and Imaging with Scanning Transmission Electron Microscopy

2001 ◽  
Vol 706 ◽  
Author(s):  
Satishkumar B. Chikkannanavar ◽  
Andreas Taubert ◽  
David E. Luzzi
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Metal Chloride ◽  
Single Wall Carbon Nanotubes ◽  
Metal Nanowires ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission

AbstractNanowires of magnetic metals (Ho, Gd) have been synthesized inside the hollow interior of single wall carbon nanotubes by the sealed-tube reaction. Amongst the d- and f-series metal chlorides investigated in this study, HoCl3 and GdCl3 fill the SWNTs to a significantly higher extent than FeCl2 and CoCl2. HoCl3 and GdCl3 nanowires have been transformed into the respective metal nanowires via the reduction of the chloride nanowires. The nanowires have been imaged using high-resolution transmission electron microscopy and scanning transmission electron microscopy (STEM). X-ray energy dispersive spectroscopy carried out in conjunction with STEM confirmed the presence of metal chloride and metal nanowires.

A Structure and Morphology of Nanocomposites Composed of Carbon Nanotubes with a Varying Fraction of Platinum Nanoparticles

2014 ◽  
Vol 939 ◽  
pp. 3-10 ◽  
Author(s):  
Anna Danuta Dobrzańska-Danikiewicz ◽  
Mirosława Pawlyta ◽  
Dariusz Łukowiec
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Standard Deviation ◽  
Platinum Nanoparticles ◽  
Scanning Transmission Electron Microscopy ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
20 Nm ◽  
Metallic Impurities

A structure of nanocomposite materials consisting of carbon nanotubes with a varying fraction of platinum nanoparticles (5, 10 and 20 wt %) is compared in the paper. High-quality CNTs obtained in the CVD process, 100-200 mm long with a standard deviation of below 20% and with a diameter of 10-20 nm, with a standard deviation of below 30%, were used in the research. Raw CNTs did not contain metallic impurities or amorphous carbon deposits. An indirect method of bonding the earlier produced platinum nanoparticles to the surface of functionalised carbon nanotubes was employed to deposit platinum nanoparticles onto the surface of carbon nanotubes. A full array of changes in the loading of carbon nanotubes’ surface with platinum nanoparticles was achieved as a result of the experiments performed, starting with homogenous deposition to the clearly developed large agglomerations of platinum nanoparticles. The studies carried out using scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy and X-ray structural analysis have confirmed differences in the morphology, homogeneity and density of coating the carbon nanotubes’ surface with variedly concentrated platinum nanoparticles. Differences were also revealed in the structure of the newly formed nanocomposites. A nanocomposite with a 5% fraction of platinum nanoparticles demonstrates the best structure-related properties for the materials obtained.

Preparation of Palm Oil Based Carbon Nanotubes at Various Ferrocene Concentration

2011 ◽  
Vol 364 ◽  
pp. 408-411 ◽  
Author(s):  
M. S. Azmina ◽  
A.B. Suriani ◽  
A.N. Falina ◽  
M. Salina ◽  
J. Rosly ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Palm Oil ◽  
Scanning Transmission Electron Microscopy ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Prominent Peak ◽  
Scanning Electron

In this work, different ferrocene concentration (1.0-8.0 wt%) of bio-hydrocarbon palm oil precursor were utilized to investigate its effect on the characteristics of the produced carbon nanotubes (CNT). The palm oil-ferrocene mixture was vaporized at 450°C and pyrolyzed at 800°C for 30 min time in argon ambient. The CNT were analyzed using field emission scanning electron microscopy, scanning transmission electron microscopy, fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis. The analysis confirmed different diameter and morphologies of CNT were formed when different ferrocene concentration were used. FTIR spectra show the prominent peak at ~1445, 1736, 2851 and 2925 cm-1that are identified as CNT and C–Hxrespectively.

Structure of Nanocomposites Based on Carbon Nanotubes Decorated with Platinum Nanoparticles

2014 ◽  
Vol 783-786 ◽  
pp. 1503-1508 ◽  
Author(s):  
Anna Danuta Dobrzańska-Danikiewicz ◽  
Mirosława Pawlyta ◽  
Dariusz Łukowiec
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Platinum Nanoparticles ◽  
Scanning Transmission Electron Microscopy ◽  
Structure And Morphology ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
20 Nm ◽  
Metallic Impurities

A structure and morphology of the fabricated nanocomposite materials composed of carbon nanotubes and platinum nanoparticles is reported in the paper. High quality CNTs obtained in the CVD process with a long of 100-200 mm and diameter of 10-20 nm were used in the research. Raw CNTs did not contain metallic impurities or amorphous carbon deposits. An indirect method of bonding the earlier produced platinum nanoparticles to the surface of functionalised carbon nanotubes was used to produce carbon nanotubes – platinum nanoparticles system. The main aim of current research was structure and morphology investigation of obtained nanocomposite using Transmission Electron Microscopy (TEM), Scanning Transmission Electron Microscopy (STEM) and X-ray structure analysis (XRD).

High-Voltage Scanning Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 6-7
Author(s):  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Wave Optics ◽  
Contrast Effects ◽  
Transmission Electron ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Types Of Information ◽  
Voltage Scanning

The comparison of scanning transmission electron microscopy (STEM) with conventional transmission electron microscopy (CTEM) can best be made by means of the Reciprocity Theorem of wave optics. In Fig. 1 the intensity measured at a point A’ in the CTEM image due to emission from a point B’ in the electron source is equated to the intensity at a point of the detector, B, due to emission from a point A In the source In the STEM. On this basis it can be demonstrated that contrast effects In the two types of instrument will be similar. The reciprocity relationship can be carried further to include the Instrument design and experimental procedures required to obtain particular types of information. For any. mode of operation providing particular information with one type of microscope, the analagous type of operation giving the same information can be postulated for the other type of microscope. Then the choice between the two types of instrument depends on the practical convenience for obtaining the required Information.

Scanning Transmission Electron Microscopy of Polyethylene Crystals

1980 ◽  
Vol 38 ◽  
pp. 242-245
Author(s):  
F. Khoury ◽  
L. H. Bolz
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystallization Temperature ◽  
Scanning Transmission Electron Microscopy ◽  
Growth Habit ◽  
Lateral Growth ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Growth Habits

The lateral growth habits and non-planar conformations of polyethylene crystals grown from dilute solutions (<0.1% wt./vol.) are known to vary depending on the crystallization temperature.1-3 With the notable exception of a study by Keith2, most previous studies have been limited to crystals grown at <95°C. The trend in the change of the lateral growth habit of the crystals with increasing crystallization temperature (other factors remaining equal, i.e. polymer mol. wt. and concentration, solvent) is illustrated in Fig.l. The lateral growth faces in the lozenge shaped type of crystal (Fig.la) which is formed at lower temperatures are {110}. Crystals formed at higher temperatures exhibit 'truncated' profiles (Figs. lb,c) and are bound laterally by (110) and (200} growth faces. In addition, the shape of the latter crystals is all the more truncated (Fig.lc), and hence all the more elongated parallel to the b-axis, the higher the crystallization temperature.

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