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Title: Excitation temperature of a solution plasma during nanoparticle synthesis

Abstract

Excitation temperature of a solution plasma was investigated by spectroscopic measurements to control the nanoparticle synthesis. In the experiments, the effects of edge shielding, applied voltage, and electrode material on the plasma were investigated. When the edge of the Ni electrode wire was shielded by a quartz glass tube, the plasma was uniformly generated together with metallic Ni nanoparticles. The emission spectrum of this electrode contained OH, H{sub α}, H{sub β}, Na, O, and Ni lines. Without an edge-shielded electrode, the continuous infrared radiation emitted at the edge created a high temperature on the electrode surface, producing oxidized coarse particles as a result. The excitation temperature was estimated from the Boltzmann plot. When the voltages were varied at the edge-shielded electrode with low average surface temperature by using different electrolyte concentrations, the excitation temperature of current-concentration spots increased with an increase in the voltage. The size of the Ni nanoparticles decreased at high excitation temperatures. Although the formation of nanoparticles via melting and solidification of the electrode surface has been considered in the past, vaporization of the electrode surface could occur at a high excitation temperature to produce small particles. Moreover, we studied the effects of electrodes of Ti, Fe,more » Ni, Cu, Zn, Zr, Nb, Mo, Pd, Ag, W, Pt, Au, and various alloys of stainless steel and Cu–Ni alloys. With the exception of Ti, the excitation temperatures ranged from 3500 to 5500 K and the particle size depended on both the excitation temperature and electrode-material properties.« less

Authors:
; ;  [1]
  1. Center for Advanced Research of Energy and Materials, Hokkaido University, Sapporo 060-8628 (Japan)
Publication Date:
OSTI Identifier:
22314679
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COARSE PARTICLES; ELECTRIC POTENTIAL; ELECTRODES; ELECTROLYTES; EMISSION SPECTRA; EXCITATION; GLASS; INFRARED RADIATION; MELTING; NANOPARTICLES; PARTICLE SIZE; PLASMA; SHIELDING; SOLIDIFICATION; STAINLESS STEELS; SURFACES; SYNTHESIS; TEMPERATURE RANGE 1000-4000 K; TEMPERATURE RANGE OVER 4000 K

Citation Formats

Saito, Genki, E-mail: genki@eng.hokudai.ac.jp, Nakasugi, Yuki, and Akiyama, Tomohiro. Excitation temperature of a solution plasma during nanoparticle synthesis. United States: N. p., 2014. Web. doi:10.1063/1.4894156.
Saito, Genki, E-mail: genki@eng.hokudai.ac.jp, Nakasugi, Yuki, & Akiyama, Tomohiro. Excitation temperature of a solution plasma during nanoparticle synthesis. United States. doi:10.1063/1.4894156.
Saito, Genki, E-mail: genki@eng.hokudai.ac.jp, Nakasugi, Yuki, and Akiyama, Tomohiro. Thu . "Excitation temperature of a solution plasma during nanoparticle synthesis". United States. doi:10.1063/1.4894156.
@article{osti_22314679,
title = {Excitation temperature of a solution plasma during nanoparticle synthesis},
author = {Saito, Genki, E-mail: genki@eng.hokudai.ac.jp and Nakasugi, Yuki and Akiyama, Tomohiro},
abstractNote = {Excitation temperature of a solution plasma was investigated by spectroscopic measurements to control the nanoparticle synthesis. In the experiments, the effects of edge shielding, applied voltage, and electrode material on the plasma were investigated. When the edge of the Ni electrode wire was shielded by a quartz glass tube, the plasma was uniformly generated together with metallic Ni nanoparticles. The emission spectrum of this electrode contained OH, H{sub α}, H{sub β}, Na, O, and Ni lines. Without an edge-shielded electrode, the continuous infrared radiation emitted at the edge created a high temperature on the electrode surface, producing oxidized coarse particles as a result. The excitation temperature was estimated from the Boltzmann plot. When the voltages were varied at the edge-shielded electrode with low average surface temperature by using different electrolyte concentrations, the excitation temperature of current-concentration spots increased with an increase in the voltage. The size of the Ni nanoparticles decreased at high excitation temperatures. Although the formation of nanoparticles via melting and solidification of the electrode surface has been considered in the past, vaporization of the electrode surface could occur at a high excitation temperature to produce small particles. Moreover, we studied the effects of electrodes of Ti, Fe, Ni, Cu, Zn, Zr, Nb, Mo, Pd, Ag, W, Pt, Au, and various alloys of stainless steel and Cu–Ni alloys. With the exception of Ti, the excitation temperatures ranged from 3500 to 5500 K and the particle size depended on both the excitation temperature and electrode-material properties.},
doi = {10.1063/1.4894156},
journal = {Journal of Applied Physics},
number = 8,
volume = 116,
place = {United States},
year = {Thu Aug 28 00:00:00 EDT 2014},
month = {Thu Aug 28 00:00:00 EDT 2014}
}
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