Synthesis of carbon nanotubes by a plasma based pulsed electron beam generator

Goktas, H.
Ayhan, U. B.
Gündüz, Güngör
Disbudak, H.
Eryilmaz, E.
Oke, G.
Cicek, B.
Somer, M.
Carbon nanotubes (CNTs) were synthesized by using a plasma based electron beam generator, which has a fast filamentary discharge formed from the superposition of an ordinary low-pressure dc glow and a high-current pulsed discharge. To our knowledge, CNTs are synthesized for the first time by this method. Acetylene was used as the carbon source and the iron catalyst coated silica substrates were prepared by the sol-gel technique. The silica plates were first coated with an appropriate iron (III) nitrate solution. After calcination and reduction with hydrogen nano iron particles were formed on the plates. The products were collected from two different zones of the e-beam generator. The products were characterized by transmission electron microscopy and Raman spectroscopy.


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Hasanlı, Nızamı (IOP Publishing, 2012-06-01)
The optical properties of Tl2Ga2Se3S layered crystals have been studied through transmission and reflection measurements in the photon energy range 1.13-2.82 eV. The optical indirect and direct transitions with band gap energies of 2.15 and 2.54 eV, respectively, were determined from the analysis of absorption data at room temperature. The dispersion of refractive index is discussed in terms of the Wemple-DiDomenico single-effective oscillator model. The refractive index dispersion parameters, namely oscill...
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QASRAWI, ATEF FAYEZ HASAN; Hasanlı, Nızamı; Ilaiwi, K. F. (IOP Publishing, 2008-07-01)
The optoelectronic properties of Bridgman method-grown Ga(4)Se(3)S single crystals have been investigated by means of room temperature electrical resistivity, temperature-dependent photosensitivity and temperature-dependent optical absorption. The photosensitivity was observed to increase with decreasing temperature, the illumination dependence of which was found to exhibit monomolecular recombination in the bulk at 300 K. The absorption coefficient, which was calculated in the incident photon energy range ...
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Qasrawi, A. F.; Hasanlı, Nızamı (IOP Publishing, 2007-09-01)
The structural and optical properties of Bridgman method grown Tl2InGaSe4 crystals have been investigated by means of room temperature x-ray diffraction, and transmittance and reflectance spectral analysis, respectively. The x-ray diffraction technique has shown that Tl2InGaSe4 is a single phase crystal of a monoclinic unit cell that exhibits the lattice parameters of a = 0.77244 nm, b = 0.64945 nm, c = 0.92205 nm and beta = 95.03 degrees . The optical data have revealed an indirect allowed transition band ...
Radiative damping of whistlers in a dense magnetoactive plasma waveguide
Yilmaz, A; Oke, G; Rukhadze, A; Bilikmen, S (IOP Publishing, 1996-06-01)
The absorption of whistler waves in a magnetized cylindrical plasma due to coupling with oblique Langmuir waves is investigated. Two types of mechanisms exist for whistler absorption. The first one is related to the excitation of Langmuir waves in the volume of the dense plasma and their subsequent absorption due to the electron collisions. The second one is the emission of Langmuir waves outside of the cylindrical plasma when it is surrounded by the rare plasma. The relation between these whistler absorpti...
Transport studies of carbon-rich a-SiCx : H film through admittance and deep-level transient spectroscopy measurements
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An intrinsic, carbon- rich a- SiCx: H thin film, prepared by the plasma- enhanced chemical vapour deposition ( PECVD) technique, has been studied mainly by AC admittance and small- pulse deep- level transient spectroscopy ( DLTS) measurements on an Al/ a- SiCx: H/ p- Si metal - insulator - semiconductor ( MIS) structure. The effects of measurement temperature, voltage and small- signal AC modulation frequency on the MIS capacitor are qualitatively and quantitatively described. The kinetics of charge injecti...
Citation Formats
H. Goktas et al., “Synthesis of carbon nanotubes by a plasma based pulsed electron beam generator,” PHYSICA SCRIPTA, pp. 145–147, 2006, Accessed: 00, 2020. [Online]. Available: