Characterization of Co-catalyzed Multiwalled Carbon Nanotubes by High-Resolution Transmission Electron Microscopy

2002 ◽  
Vol 737 ◽  
Author(s):  
Chih-Chin Wang ◽  
Chuan-Pu Liu ◽  
Ruo-Mei Liu ◽  
Kuen-Hou Liao
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Multiwalled Carbon Nanotubes ◽  
Microwave Plasma ◽  
Cobalt Catalysts ◽  
Multiwalled Carbon ◽  
Co Catalysts ◽  
Transmission Electron

ABSTRACTThe dependence of characteristics of multiwalled carbon nanotubes (MWCNT) on the microstructure of cobalt catalysts are intensively investigated by high-resolution transmission electron microscopy (HREM). The cobalt catalysts are prepared by either molecule beam epitaxy (MBE) or by DC magnetron sputtering, followed by MWCNT growth by microwave plasma CVD. The MBE-grown Co thin films consist of large epitaxial grains, whereas the Co nanoparticles of FCC or HCP crystal structures can be directly grown on Si(001) substrates by sputtering. Various HREM technologies are applied to completely characterize the microstructures of those Co catalysts and MWCNT. The results reveal that the morphology and microstructures of MWCNT are greatly controlled by the characteristics of Co catalysts. Better quality of carbon nanotube can be grown by FCC cobalt rather than HCP cobalt. The different effects of cobalt catalysts on MWCNT are discussed in this paper.

Structure of Antimony Sulfoiodide Ultrasonically Prepared in Carbon Nanotubes

2010 ◽  
Vol 163 ◽  
pp. 88-92 ◽  
Author(s):  
Danuta Stróż ◽  
M. Nowak ◽  
M. Jesionek ◽  
Katarzyna Bałdys
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Multiwalled Carbon Nanotubes ◽  
Medical Applications ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Antimony Sulfoiodide

This paper presents a brand new hybrid material on the nanometric scale: the antimony sulfoiodide (SbSI) within carbon nanotubes (CNTs). It was prepared in CNTs ultrasonically by using elemental antimony (Sb), sulfur (S) and iodide (I) in the presence of methanol under ultrasonic irradiation (34 kHz, 2.6 W/cm2). The sonochemical process was leaded for 3 hours at 323 K. The antimony sulfoiodide (SbSI) consisted in multiwalled carbon nanotubes (CNTs) were characterized high-resolution transmission electron microscopy (HRTEM). These investigations exhibit that the SbSI filling the CNTs has single-crystal structure in nature and in the form of multiwalled carbon nanotubes. The SbSI grown in CNTs are very promising materials for further investigations as well as for some industrial and medical applications.

Morphology and thermal properties of nanocomposites based on chiral poly(ester-imide) matrix reinforced by vitamin B1 functionalized multiwalled carbon nanotubes

2016 ◽  
Vol 51 (16) ◽  
pp. 2291-2300 ◽  
Author(s):  
Shadpour Mallakpour ◽  
Samaneh Soltanian
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Vitamin B1 ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Functionalized Multiwalled Carbon Nanotubes ◽  
Scanning Electron

Chemical functionalization of carboxylated multiwalled carbon nanotubes with vitamin B1 was carried out under ultrasonic irradiation. The functionalized nanotubes were embedded in a chiral and biodegradable poly(ester-imide) to prepare multiwalled carbon nanotubes reinforced polymer nanocomposites. Optically active poly(ester-imide) was synthesized by step-growth polymerization of aromatic diol and amino acid based diacid. The vitamin B1 functionalized multiwalled carbon nanotubes and the resulting nanocomposites were examined using Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, and field-emission scanning electron microscopy. Thermogravimetric analysis results indicated that temperature at 10% weight loss was increased from 409℃ for pure PEI to 419℃, 427℃, and 430℃ for nanocomposites containing 5%, 10%, and 15% functionalized multiwalled carbon nanotubes, respectively. The Fourier-transform scanning electron microscopy and transmission electron microscopy images exhibited that the functionalized multiwalled carbon nanotubes were separated individually and enwrapped by polymer chains.

scholarly journals One-Step Route to Synthesize Multiwalled Carbon Nanotubes Filled with MgO Nanorods

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Jing Liu ◽  
Chunli Guo ◽  
Xiaojian Ma ◽  
Changhui Sun ◽  
Fengxia Li ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Transmission Electron ◽  
Good Crystallinity ◽  
One Step ◽  
Walled Cnts

Multiwalled carbon nanotubes filled with MgO nanorods were synthesized through the reaction of ethanol and Mg powder in the presence ofTiO2at 400C°. X-ray powder diffraction indicated that the sample was composed of graphite and cubic MgO. Transmission electron microscopy studies showed that multi-walled CNTs with the outer diameters of 70–130 nm were filled with discontinuous MgO nanorods whose diameter was in the range of 25–40 nm. The ratios of the band intensities(ID/IG=0.67)in Raman spectrum implied that carbon nanotubes had good crystallinity. The influence of correlative reaction factors on the morphology of the sample and the possible formation mechanism were discussed.

Experimental and theoretical studies on the mechanism for chemical oxidation of multiwalled carbon nanotubes

RSC Advances ◽  
2014 ◽  
Vol 4 (55) ◽  
pp. 28826-28831 ◽  
Author(s):  
B. M. Maciejewska ◽  
M. Jasiurkowska-Delaporte ◽  
A. I. Vasylenko ◽  
K. K. Kozioł ◽  
S. Jurga
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Chemical Oxidation ◽  
Theoretical Studies ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Experimental And Theoretical Studies

In this study, the oxidation of multiwalled carbon nanotubes (MWCNTs) sonicated and/or refluxed in acids (H2SO4/HNO3) was investigated using a combination of high-resolution transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and ab initio computational methods.

scholarly journals Encapsulation of Fullerenes: A Versatile Approach for the Confinement and Release of Materials Within Open-Ended Multiwalled Carbon Nanotubes

2021 ◽  
Vol 9 ◽  
Author(s):  
Stefania Sandoval ◽  
Gerard Tobias
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Inorganic Material ◽  
Single Step ◽  
The Other ◽  
Multiwalled Carbon ◽  
Mild Conditions ◽  
Transmission Electron

We have employed fullerenes as versatile agents to “cork” the open tips of multiwalled carbon nanotubes (MWCNTs), and as promoting species for the release of the inorganic material filled within the nanotubes’ cavities. High Z element compounds, namely, PbI2, ZnI2, and CeI3, were chosen to easily determine the presence of the filler inside the hosting nanotubes by transmission electron microscopy (TEM). Fullerenes can isolate inorganic nanostructures confined within the hollow cavities of MWCNTs, which allows the removal of the external material remnant after the filling. Otherwise, taking advantage of the affinity of fullerenes with selected solvents, we have confirmed the ability of the C60 molecules to promote the displacement of the inorganic guest from the host. We propose two different strategies to trigger the release, employing vapor and liquid phase treatments. The first protocol involves annealing filled MWCNTs in presence of fullerenes (to obtain C60PbI2@MWCNTs) and the subsequent washing of the sample in ethanol under mild conditions. On the other hand, the simultaneous introduction of the C60 molecules and the liberation of the guest are produced by a single step wet procedure; the latter being potentially useful when materials that are not stable at high temperatures are employed for filling.

scholarly journals Novel Nanohybrids Based on Supramolecular Assemblies of Meso-tetrakis-(4-sulfonatophenyl) Porphyrin J-aggregates and Amine-Functionalized Carbon Nanotubes

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 669 ◽  
Author(s):  
Mariachiara Trapani ◽  
Antonino Mazzaglia ◽  
Anna Piperno ◽  
Annalaura Cordaro ◽  
Roberto Zagami ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Fluorescence Emission ◽  
Resonance Light Scattering ◽  
Therapeutic Window ◽  
Multiwalled Carbon ◽  
Experimental Conditions ◽  
Transmission Electron ◽  
J Aggregates

The ability of multiwalled carbon nanotubes (MWCNTs) covalently functionalized with polyamine chains of different length (ethylenediamine, EDA and tetraethylenepentamine, EPA) to induce the J-aggregation of meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) was investigated in different experimental conditions. Under mild acidic conditions, protonated amino groups allow for the assembly by electrostatic interaction with the diacid form of TPPS, leading to hybrid nanomaterials. The presence of only one pendant amino group for a chain in EDA does not lead to any aggregation, whereas EPA (with four amine groups for chain) is effective in inducing J-aggregation using different mixing protocols. These nanohybrids have been characterized through UV/Vis extinction, fluorescence emission, resonance light scattering and circular dichroism spectroscopy. Their morphology and chemical composition have been elucidated through transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). TEM and STEM analysis evidence single or bundles of MWCNTs in contact with TPPS J-aggregates nanotubes. The nanohybrids are quite stable for days, even in aqueous solutions mimicking physiological medium (NaCl 0.15 M). This property, together with their peculiar optical features in the therapeutic window of visible spectrum, make them potentially useful for biomedical applications.

A Study of the Origin of Band-A Emission in Homoepitaxial Diamond Thin Films

1999 ◽  
Vol 588 ◽  
Author(s):  
Daisuke Takeuchi ◽  
Hideyuki Watanabe ◽  
Sadanori Yamanaka ◽  
Hideyo Okushi ◽  
Koji Kajimura ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Grain Boundaries ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Plasma Chemical Vapor Deposition ◽  
Transmission Electron ◽  
Excitonic Emission

AbstractThe band-A emission (around 2.8 eV) observed in high quality (device-grade) homoepitaxial diamond films grown by microwave-plasma chemical vapor deposition (CVD) was studied by means of scanning cathodoluminescence spectroscopy and high-resolution transmission electron microscopy. Recent progress in our study on homoepitaxial diamond films was obtained through the low CH4/H2 conditions by CVD. These showed atomically flat surfaces and the excitonic emission at room temperature, while the band-A emission (2.95 eV) decreased. Using these samples, we found that the band-A emission only appeared at unepitaxial crystallites (UC) sites, while other flat surface parts still showed the excitonic emission. High-resolution transmission electron microscopy revealed that there were grain boundaries which contained π-bonds in UC. This indicates that one of the origin of the band-A emission in diamond films is attributed to π bonds of grain boundaries.

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