Structure And Morphology Of Carbon Nanofibers Synthesized On Cu Nanopowders

2016 ◽  
Vol 11 (3) ◽  
pp. 62-71
Author(s):  
Gulmira Partizan ◽  
Batyr Mansurov ◽  
Botagoz Medyanova ◽  
Аizhan Koshanova ◽  
Madina Mansurova ◽  
...  
Keyword(s):  
Carbon Nanofibers ◽  
Chemical Vapor ◽  
Temperature Growth ◽  
Copper Clusters ◽  
Transmission Electron ◽  
Amorphous Nature ◽  
Diffraction Patterns ◽  
Stable Growth ◽  
Different Diameters ◽  
Copper Nanopowders

This article presents the results of experiments on the synthesis of carbon nanofibers by thermal chemical vapor deposition using copper nanopowders obtained by electric explosion of wire as catalysts. Stable growth of carbon nanofibers was carried out at temperatures significantly lower than normally used. The process parameters that are optimal for low-temperature growth of carbon nanofibers have been identified during the performed experiments. The synthesized samples have different diameters and morphology (from spiral to direct). Copper clusters are both at the ends and inside the fibers. The results of IR spectroscopy indicate that the structure of the obtained carbon nanofibers is polymeric. X-ray analysis revealed the presence of a halo on the diffraction patterns at small values of the angle 2θ, which proves that the grown structures have an amorphous nature. There are no groups that are responsible for long-range order in all Raman spectra. Studies by transmission electron microscopy showed that nanostructures do not have an internal channel and nanofibers are solid.

scholarly journals Synthesis of Carbon Nanofibers on Copper Nanopowders by Low-Temperature CVD

2017 ◽  
Vol 18 (4) ◽  
pp. 283 ◽  
Author(s):  
G. Partizan ◽  
B.Z. Mansurov ◽  
B.S. Medyanova ◽  
А.B. Koshanova ◽  
M.E. Mansurova ◽  
...  
Keyword(s):  
Low Temperature ◽  
Carbon Nanofibers ◽  
Chemical Vapor ◽  
Temperature Growth ◽  
Copper Clusters ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
Stable Growth ◽  
Different Diameters ◽  
Copper Nanopowders

The article presents the results of experiments on the synthesis of carbon nanofibers by thermal chemical vapor deposition using copper nanopowders obtained by electric explosion of wire as catalysts. Stable growth of carbon nanofibers was carried out at temperatures significantly lower than normally used. The process parameters that are optimal for low-temperature growth of carbon nanofibers have been identified during the performed experiments. The synthesized samples have different diameters and morphology (from spiral to direct). Copper clusters are both at the ends and inside the fibers. The results of IR spectroscopy indicate that the structure of the obtained carbon nanofibers is polymeric. X-ray analysis revealed the presence of a halo on the diffraction patterns at small values of the angle 2θ, which proves that the grown<br />structures have an amorphous nature. There are no groups that are responsible for long-range order in all Raman spectra. Studies by transmission electron microscopy showed that nanostructures do not have an internal channel and nanofibers are solid.

A Novel TEM Technique for Characterizing As-Grown CVD Diamond Films

1991 ◽  
Vol 49 ◽  
pp. 956-957 ◽  
Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton
Keyword(s):  
Diamond Films ◽  
Chemical Vapor ◽  
Growth Direction ◽  
Dark Field ◽  
Growth Surface ◽  
Specimen Preparation ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
First Time ◽  
Microstructural Studies

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.

The Microstructure of Fe7C3 Formed at 300°C by Plasma Enhanced Chemical Vapor Deposition (PECVD)

1993 ◽  
Vol 313 ◽  
Author(s):  
H. Siriwardane ◽  
P. Fraundorf ◽  
J.W. Newkirk ◽  
O.A. Pringle ◽  
W.J. James
Keyword(s):  
Oxidation Process ◽  
Iron Carbide ◽  
Chemical Vapor ◽  
Carbon Films ◽  
Corrosion And Wear ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Iron Phase ◽  
Diffraction Patterns

Thin iron carbide films were prepared by introducing iron penta carbonyl (FeCO5) and hydrogen (H2) into a glow discharge. The films are of potential interest in corrosion and wear resistant applications. X-ray diffraction data of films (≈ 7000 Å thick) deposited on glass at 300°C evidenced only Fe7C3. Thinner films were required for examination by analytical and high resolution transmission electron Microscopy. Therefore, two sets of films (“thin” < 200 Å and “thick” ≈ 800 Å) were plasma-deposited on carbon or holey carbon films supported on copper grids. The thin TEM specimens exhibited a fine texture and gave rise to ring diffraction patterns, whereas the thick TEM specimens evidenced two types of structure: (i) half-Micron sized grains separated from one another by 1–2 Microns on the support, although sometimes interconnected by single crystal platelets and (ii) 300 Å grapelike clumps of 100–200 Å crystals, each individually surrounded by a 50 Å non-crystalline coating. The latter structure may result from a post-formation oxidation process which expels carbon from the iron phase into grain boundaries.

Carbon nanofibers grown on carbon fibers by chemical vapor deposition using the iron catalyst

2021 ◽  
Vol 95 ◽  
pp. 24-28
Author(s):  
Vuong Hoang Van ◽  
◽  
Duc Nguyen Van
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanofibers ◽  
Carbon Fibers ◽  
Vapour Deposition ◽  
Iron Catalyst ◽  
Chemical Vapour ◽  
Chemical Vapor ◽  
Processing Temperature ◽  
Gas Composition ◽  
Transmission Electron

Carbon nanofibers (CNFs) were synthesized by the catalytic chemical vapour deposition (CCVD) process using iron catalyst below the iron-carbon eutetic temperature (1147 oC). CNFs were formed on carbon fibers as substrates at the growth temperatures of 750, 800, and 850 oC. The effect of processing temperature on the formation and the morphology of CNFs was studied. Moreover, the effect of composition of gase mixture (C2H4, H2, and Ar) on the morphology of CNFs was also performed. The morphology and microstructure of as-obtained CNFs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electron diffraction (ED). Results revealed that temperature and gas composition play an important role in forming of CNFs.

Investigation of the low angle grain boundaries in highly oriented diamond films via transmission electron microscopy

1994 ◽  
Vol 9 (10) ◽  
pp. 2487-2489 ◽  
Author(s):  
F.R. Sivazlian ◽  
J.T. Glass ◽  
B.R. Stoner
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Boundary ◽  
Microwave Plasma ◽  
Chemical Vapor ◽  
Plan View ◽  
Plasma Chemical Vapor Deposition ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
Defect Densities

Highly oriented diamond thin films grown on silicon via microwave plasma chemical vapor deposition were examined by transmission electron microscopy. In the plan view, defects appearing at the grain boundary were easily observed. (100) faceted grains that appeared to have coalesced were connected at their interfaces by dislocations characteristic of a low angle grain boundary. From Burgers vector calculations and electron diffraction patterns, the azimuthal rotation between grains was measured to be between 0 and 6°. The defect densities of these films are compared to reports from (100) textured randomly oriented films, and the relative improvement due to the reduction of misorientation and grain boundary angles is discussed.

Continuous Carbon Nanofibers For Nanofiber Composites

2001 ◽  
Vol 702 ◽  
Author(s):  
Yuris Dzenis ◽  
Yongkui Wen
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanofibers ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Good Potential ◽  
Diffraction Patterns

ABSTRACTContinuous carbon nanofibers were manufactured using electrospinning technique. The as-spun polyacrylonitrile (PAN) nanofibers were stabilized and carbonized to convert them into carbon nanofibers. The diameters of typical carbon nanofibers were in the range from 100 -500 nanometers. Compared to the vapor grown carbon nanofibers, the electronspun carbon nanofibers were continuous, uniform in diameter, and solid. The electrospun nanofiber samples did not require purification. The carbon nanofibers were characterized by scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Electron and X-ray diffraction patterns were obtained and analyzed. Nanocomposites of epoxy resin reinforced with as-spun PAN and carbon nanofibers were fabricated and analyzed. The results showed good potential of continuous carbon nanofibers for nanocomposite and other applications.

High-Resolution Transmission Electron Microscope Analysis of Tungsten Carbide Thin Films

1998 ◽  
Vol 520 ◽  
Author(s):  
Wentao Qin ◽  
W. Shih ◽  
J. Lib ◽  
W. James ◽  
H. Siriwardaneane ◽  
...  
Keyword(s):  
Thin Films ◽  
Electron Microscope ◽  
High Resolution ◽  
Tungsten Carbide ◽  
Transmission Electron Microscope ◽  
Chemical Vapor ◽  
Unit Cell Size ◽  
Aspect Ratios ◽  
Transmission Electron ◽  
Diffraction Patterns

ABSTRACTElectron diffraction patterns and high-resolution transmission electron microscope (HREM) images show that the dominant phase in tungsten carbide thin films grown by plasma enhanced chemical vapor deposition is WC(1−x). The f.c.c crystal structure and the unit cell size of WC(1−x) have been determined via electron powder diffraction. The two largest and most dominant spacings in HREM images are the {111} and {002} spacings of WC(1−x). Cross lattice fringes along the two most densely populated zones of WC(1−x) are seen. The sizes and aspect ratios of nano-crystals have been measured from HREM images. Stereo analysis of individual nano-crystals has been done. Confirmation of the 3-D structure of WC(1−x) via spacings larger than 0.15 nm will require a tilt larger than 35° between images.

Synthesis of Si-O-C Nanoballs by CVD of Polydimethylsiloxane

2012 ◽  
Vol 454 ◽  
pp. 114-117
Author(s):  
Xia Yuan ◽  
Yu Liang An ◽  
Hong Chao Sui ◽  
Chen Zhang
Keyword(s):  
Chemical Vapor ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cvd Method ◽  
Silicon Carbon ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
Two Populations ◽  
Scan Electronic Microscope ◽  
Electronic Microscope

Here we reported that the Si-O-C nanoballs (SCONBs) were yielded from polyorganosiloxane, polydimethylsiloxane, by chemical vapor deposition (CVD) method. The composite nanoballs with a range of diameters from 50 to 200nm were composed of silicon, carbon and oxygen based on analysis of EDX. At the transmission electron microscope(TEM) and scan electronic microscope(SEM), two populations of nanoballs were found: around 200nm and 500nm. X-ray diffraction patterns demonstrated that the nanoballs were dominatingly amorphous. Temperature played an key role in size distribution of Si-O-C nanoballs, and the 850–900°C temperature range was typical for nanoparticles growth via CVD.

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