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Title: Characterization of bismuth nanospheres deposited by plasma focus device

Abstract

A new method for producing thin layer of bismuth nanospheres based on the use of low energy plasma focus device is demonstrated. Various techniques such as scanning electron microscopy, Rutherford backscattering spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to characterize the morphology and the composition of the nanospheres. Experimental parameters may be adjusted to favour the formation of bismuth nanospheres instead of microspheres. Therefore, the formation of large surface of homogeneous layer of bismuth nanospheres with sizes of below 100 nm can be obtained. The natural snowball phenomenon is observed to be reproduced in nanoscale where spheres roll over the small nanospheres and grow up to bigger sizes that can reach micro dimensions. The comet-like structure, a reverse phenomenon to snowball is also observed.

Authors:
 [1]; ;  [2];  [3]
  1. IBA Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)
  2. Physics Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)
  3. Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)
Publication Date:
OSTI Identifier:
22413085
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BISMUTH; ELECTRON MICROSCOPY; LAYERS; MICROSPHERES; MORPHOLOGY; NANOSTRUCTURES; PLASMA FOCUS DEVICES; RAMAN SPECTROSCOPY; RUTHERFORD BACKSCATTERING SPECTROSCOPY; SPHERES; SURFACES; THIN FILMS; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Ahmad, M., E-mail: cscientific2@aec.org.sy, Al-Hawat, Sh., Akel, M., and Mrad, O. Characterization of bismuth nanospheres deposited by plasma focus device. United States: N. p., 2015. Web. doi:10.1063/1.4907579.
Ahmad, M., E-mail: cscientific2@aec.org.sy, Al-Hawat, Sh., Akel, M., & Mrad, O. Characterization of bismuth nanospheres deposited by plasma focus device. United States. doi:10.1063/1.4907579.
Ahmad, M., E-mail: cscientific2@aec.org.sy, Al-Hawat, Sh., Akel, M., and Mrad, O. Sat . "Characterization of bismuth nanospheres deposited by plasma focus device". United States. doi:10.1063/1.4907579.
@article{osti_22413085,
title = {Characterization of bismuth nanospheres deposited by plasma focus device},
author = {Ahmad, M., E-mail: cscientific2@aec.org.sy and Al-Hawat, Sh. and Akel, M. and Mrad, O.},
abstractNote = {A new method for producing thin layer of bismuth nanospheres based on the use of low energy plasma focus device is demonstrated. Various techniques such as scanning electron microscopy, Rutherford backscattering spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to characterize the morphology and the composition of the nanospheres. Experimental parameters may be adjusted to favour the formation of bismuth nanospheres instead of microspheres. Therefore, the formation of large surface of homogeneous layer of bismuth nanospheres with sizes of below 100 nm can be obtained. The natural snowball phenomenon is observed to be reproduced in nanoscale where spheres roll over the small nanospheres and grow up to bigger sizes that can reach micro dimensions. The comet-like structure, a reverse phenomenon to snowball is also observed.},
doi = {10.1063/1.4907579},
journal = {Journal of Applied Physics},
number = 6,
volume = 117,
place = {United States},
year = {Sat Feb 14 00:00:00 EST 2015},
month = {Sat Feb 14 00:00:00 EST 2015}
}
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  • A Mather-type small plasma focus device was operated in air filling in the pressure range of 0.5 to 1.0 Torr and capacitor bank charging voltage of 13{endash}15 kV. A strong focusing action was observed in this pressure range. Magnetic probe signals at various axial positions were used to estimate velocity of current sheet and axial magnetic field distribution profiles. It was observed that under the present experimental conditions the magnetic field remains constant at 0.72 T from {ital z}=0.0 cm to {ital z}=8.0 cm but falls rapidly to 0.52 T at about {ital z}=14.5 cm at a fixed radial distancemore » of 2.65 cm. The magnetic field and velocity measurements indicate a current shedding effect{emdash}only 68.5{percent} of the total injected current flows into the focus region. The rapid drop of the magnetic field at {ital z}=8.0 cm suggests that further (initial shedding is at the insulator) current and mass shedding in the focus tube is significant after this value of {ital z}. Experimental values of velocity of the current sheet are compared with those of the snow plough theoretical model. {copyright} {ital 1996 American Institute of Physics.}« less