High-density aligned carbon nanotubes with uniform diameters

2003 ◽  
Vol 18 (7) ◽  
pp. 1686-1690 ◽  
Author(s):  
P. J. Cao ◽  
Y. S. Gu ◽  
H. W. Liu ◽  
F. Shen ◽  
Y. G. Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
High Density ◽  
Large Area ◽  
Transmission Electron ◽  
Area 7 ◽  
Aligned Carbon Nanotubes ◽  
High Resolution Tem ◽  
Electron Energy Loss

A new method was found to synthesize large-area (7 × 15 mm2), high-density (higher than 109 cm−2), aligned carbon nanotubes (CNTs) with uniform diameters on a silica wafer. Ferrocene/melamine mixtures were pyrolyzed through a three-step process in an Ar atmosphere in a single-stage furnace. The structure and composition of the CNTs were investigated by scanning electron microscopy, transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), and electron energy-loss spectroscopy (EELS). It was found that these nanotubes have uniform outer diameters of about 22 nm and varying lengths from 10 to 40 μm. High-resolution TEM images showed that CNT is composed of graphite-like layers arranged in a stacked-cup-like structure. XPS results showed that the layer covering the tops of the aligned CNTs consists of carbon and iron. The EELS spectrum showed that these tubes are pure carbon.

Study on Nanometer Size Structures in the Cr-Mo Electroplated Layer Using Transmission Electron Microscopy and Positron Lifetime Measurement

2011 ◽  
Vol 675-677 ◽  
pp. 247-250 ◽  
Author(s):  
Yoshio Tanita ◽  
Daiji Matsui ◽  
Hiroshi Fukushima
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Dark Field Image ◽  
Dark Field ◽  
High Density ◽  
Positron Annihilation Lifetime ◽  
Small Crystal ◽  
Transmission Electron ◽  
High Resolution Tem ◽  
Crystal Grains

Micro- and nano-structures of the Cr-Mo electroplated layers were studied mainly by Transmission Electron Microscopy (TEM), High Resolution TEM (HRTEM) and Positron Annihilation Lifetime Spectroscopy (PALS). These electroplated layers which were deposited in Cr-Mo electrolyte containing an organic sulfonic acid, showed surface structures having severe ups and downs of small crystal grains. Both selected area diffraction and dark-field image of TEM confirmed the presence of very small crystal grains of less than 50 nm. These small crystal grains exhibited textured structure when the electrolyte contained an organic sulfonic catalyst. PALS results indicated the presence of high density nano-size voids, and HRTEM analysis confirmed the presence of high density voids of 1 nm to 2 nm in diameter. Size and density of these nano-voids increased with the amount of catalyst in the electrolyte.

Synthesis and Characteristics of Hierarchical Nanostructure Fe3O4 Coated Multi-Walled Carbon Nanotubes

2014 ◽  
Vol 926-930 ◽  
pp. 258-261
Author(s):  
Jing Heng Deng ◽  
Kan Ping Yu ◽  
Jian Guo Xie
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Solvothermal Process ◽  
X Ray ◽  
Hierarchical Nanostructure ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Scanning Electron

Hierarchical nanostructure Fe3O4/multi-walled carbon nanotubes (Fe3O4/MWCNTs) were prepared by solvothermal process using acid treated MWCNTs and iron acetylacetonate in ethylene glycol as reduction reagent. The materials were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). The results showed that petal-like hierarchical Fe3O4 grew on MWCNTs and the Fe3O4 nanoparticles had diameters in the range of 55-110 nm. It was a facile approach to grow hierarchical nanoFe3O4.

Effect of growth conditions on B-doped carbon nanotubes

2006 ◽  
Vol 21 (12) ◽  
pp. 3058-3064 ◽  
Author(s):  
Sara M.C. Vieira ◽  
Odile Stéphan ◽  
David L. Carroll
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Arc Discharge ◽  
Amorphous Material ◽  
Graphite Powder ◽  
Growth Conditions ◽  
Multiwalled Carbon ◽  
Boron Doped ◽  
Transmission Electron ◽  
Electron Energy Loss

The modified arc-discharge technique was used for the growth of boron-doped multiwalled carbon nanotubes. A variety of weight percentages of boron and sulfur were mixed (0.5–15 wt%) with graphite powder and packed in the consumable anode. Transmission electron microscopy, Raman spectroscopy, thermogravimetric analysis (TGA), and electron energy loss spectroscopy (EELS) were used to characterize the samples. EELS indicated a small percentage of boron present (<1 at.%) in the nanotubes. Sulfur was used primarily to enhance boron incorporation; however, Raman and TGA measurements indicated fewer defects and/or amorphous material present when sulfur was added.

One-step Synthesis of Carbon Nanotubes Network with Rich Oxygenated Functional Groups via Microwave Plasma in Atmospheric Pressure

MRS Advances ◽  
2020 ◽  
Vol 5 (52-53) ◽  
pp. 2679-2684
Author(s):  
Dashuai Li ◽  
Ling Tong ◽  
Bo Gao
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Atmospheric Pressure ◽  
Microwave Plasma ◽  
Ethanol Vapor ◽  
Transmission Electron ◽  
Synthesis Of Carbon Nanotubes ◽  
Oxygenated Functional Groups

AbstractAn atmospheric pressure microwave plasma tubular furnace apparatus (MPTF) for the rapid synthesis of carbon nanotubes (CNTs) has been developed. CNTs have been synthesized by an Argon-Hydrogen microwave plasma using ethanol vapor as carbon source with the furnace temperature of 800 °C at the atmospheric pressure. The synthesized CNTs have been analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and are shown to be multi-walled and tangled and chemically connected to form a high-density network with the diameter at the range of 25-70 nm. The measurement of X-ray photoelectron spectroscopy (XPS) indicates that a large number of oxygenated functional groups grown on the surface of CNTs. These properties proved that the CNTs could be utilized as nanoscale templates for various applications.

Carbon nanotubes and metalloporphyrins and metallophthalocyanines-based materials for electroanalysis

2012 ◽  
Vol 16 (07n08) ◽  
pp. 713-740 ◽  
Author(s):  
José H. Zagal ◽  
Sophie Griveau ◽  
Mireya Santander-Nelli ◽  
Silvia Gutierrez Granados ◽  
Fethi Bedioui
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Hybrid Materials ◽  
Photoelectron Spectroscopy ◽  
State Of The Art ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Walled Carbon Nanotubes

We discuss here the state of the art on hybrid materials made from single (SWCNT) or multi (MWCNT) walled carbon nanotubes and MN4complexes such as metalloporphyrins and metallophthalocyanines. The hybrid materials have been characterized by several methods such as cyclic voltammetry (CV), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and scanning electrochemical microscropy (SECM). The materials are employed for electrocatalysis of reactions such as oxygen and hydrogen peroxide reduction, nitric oxide oxidation, oxidation of thiols and other pollutants.

A new route to single crystalline vanadium dioxide nanoflakes via thermal reduction

2007 ◽  
Vol 22 (7) ◽  
pp. 1921-1926 ◽  
Author(s):  
Jifa Tian ◽  
Fei Liu ◽  
Chengmin Shen ◽  
Huairuo Zhang ◽  
Tianzhong Yang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Vanadium Dioxide ◽  
Thermal Reduction ◽  
X Ray Diffraction ◽  
Large Area ◽  
Single Crystalline ◽  
X Ray ◽  
Transmission Electron ◽  
Storage Behavior

Large-area single-crystalline vanadium dioxide nanoflakes were first fabricated via a thermal reduction method in a tube furnace. The sample was characterized by x-ray diffraction, x-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results show that VO2 nanoflakes are single-crystalline with a monoclinic structure. The VO2 nanoflakes have a width of 200–300 nm, a thickness of 50–100 nm, and a length up to 1–2 μm. It is found that single-crystalline VO2 nanoflakes show a novel and complicated 5–7-step Li-storage behavior for an insertion amount of <0.6 mol lithium per mol of VO2.

Chemical Deposition Method for Synthesis of Pt-TiO2 Composite Nanotubes with Photoelectrochemical Activity

2012 ◽  
Vol 465 ◽  
pp. 276-282
Author(s):  
Zhong Hui Gao ◽  
Zhen Duo Cui ◽  
Xian Jin Yang
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Chemical Deposition ◽  
Pt Nanoparticles ◽  
High Density ◽  
Deposition Method ◽  
Photoelectrochemical Activity ◽  
X Ray ◽  
Transmission Electron ◽  
Chemical Deposition Method

Pt nanoparticles were successfully assembled in self-organized TiO2 nanotubes by a chemical deposition method. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used for characterizing the surface morphology and phase composition. Photocurrent response activity was measured. Different morphology of Pt-TiO2 NTs exhibited different photocurrent generation efficiency. High density Pt nanoparticles depositing on TiO2 NTs decreased the photocurrent of Pt-TiO2 electrodes. It was because the high density Pt nanoparticles could become the recombination centers of photoelectrons and holes.

DISPERSITY AND STABILITY MEASUREMENT OF FUNCTIONALIZED MULTIWALLED CARBON NANOTUBES IN ALCOHOLS

2008 ◽  
Vol 22 (25) ◽  
pp. 2493-2501 ◽  
Author(s):  
HUN-SIK KIM ◽  
MINSUNG KANG ◽  
WON-IL PARK ◽  
DON-YOUNG KIM ◽  
HYOUNG-JOON JIN
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Multiwalled Carbon ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Stability Measurement ◽  
The Stability

Multiwalled carbon nanotubes (MWCNTs) were dispersed in various alcohols such as methanol, ethanol and isopropanol using ultrasonication. In order to disperse the MWCNTs in the alcohols, they were treated using a mixture of H 2 SO 4 and HNO 3 (3 : 1, vol/vol). The concentration of MWCNTs was approximately 0.03 wt.% and they formed a homogeneous dispersion in the alcohol solutions. The functional groups introduced on the surface of the MWCNTs during the acid treatment were characterized by Fourier transform-infrared spectroscopy and X-ray photoelectron spectroscopy. The dispersibility of the MWCNTs in the alcohols was characterized using atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The stability of the MWCNT dispersions was also measured using a recently developed optical analyzer (Turbiscan).

scholarly journals Preparation of Al2O3 and AlN Nanotubes by Atomic Layer Deposition

2012 ◽  
Vol 1408 ◽  
Author(s):  
Cagla Ozgit ◽  
Fatma Kayaci ◽  
Inci Donmez ◽  
Engin Cagatay ◽  
Tamer Uyar ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Layer Deposition ◽  
High Resolution Tem ◽  
Uniform Wall

ABSTRACTAl2O3 and AlN nanotubes were fabricated by depositing conformal thin films via atomic layer deposition (ALD) on electrospun nylon 66 (PA66) nanofiber templates. Depositions were carried out at 200°C, using trimethylaluminum (TMAl), water (H2O), and ammonia (NH3) as the aluminum, oxygen, and nitrogen precursors, respectively. Deposition rates of Al2O3 and AlN at this temperature were ∼1.05 and 0.86 Å/cycle. After the depositions, Al2O3- and AlN-coated nanofibers were calcinated at 500°C for 2 h in order to remove organic components. Nanotubes were characterized by using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). AlN nanotubes were polycrystalline as determined by high resolution TEM (HR-TEM) and selected area electron diffraction (SAED). TEM images of all the samples reported in this study indicated uniform wall thicknesses.

scholarly journals Green Synthesis and Characterization of Carbon Nanotubes/Polyaniline Nanocomposites

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Van Hoa Nguyen ◽  
Jae-Jin Shim
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Interfacial Polymerization ◽  
Nickel Foam ◽  
Green Solvents ◽  
X Ray ◽  
Transmission Electron ◽  
Two Phases

Carbon nanotubes/polyaniline (CNT/PANI) nanocomposites were synthesized by the interfacial polymerization of aniline in the presence of CNTs using two green solvents, water and an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, [bmim][BF4]), as the two phases. The formation and incorporation of PANI on the surface of the CNTs were confirmed by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy ultraviolet-visible spectroscopy, and X-ray photoelectron spectroscopy. The analyses showed that the surface of the CNTs was coated with different morphologies of thin PANI layers depending on whether a HCl or HNO3solution was used. The thermal stability of the composites was much better than that of the bare CNTs and pure PANI. The as-prepared composites were also used to modify the nickel foam electrodes for characterization of the electrochemical properties.

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