- Fabrication and Characterization of Carbon-Coated Cu Nanopowders by Pulsed Wire Evaporation Method
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H.M. Lee, J.H. Park, S.M. Hong, Y.R. Uhm, C.K. Rhee
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J Korean Powder Metall Inst. 2009;16(4):243-248.
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DOI: https://doi.org/10.4150/KPMI.2009.16.4.243
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- Carbon-coated Cu nanopowders with core/shell structure have been successfully fabricated by pulsed wire evaporation (PWE) method, in which a mixed gas of Ar/CH_4 (10 vol.%) was used as an ambient gas. The characterization of the samples was carried out using x-ray diffraction (XRD), scanning electron microscope (SEM), and high resolution transmission electron microscope (HRTEM). It was found that the nanoparticles show a spherical morphology with the size ranging of 10-40 nm and are covered with graphite layers of 2-4 nm. When oxygen-passivated Cu nanopowders were annealed under flowing argon gas (600 and 800°C), the crystallinity of Cu_2O phase and the particle size gradually increased. On the other hand, carbon-coated Cu nanopowders remained similar to as-prepared case with no additional oxide or carbide phases even after the annealing, indicating that the metal nanoparticles are well protected by the carbon-coating layers.
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Citations
Citations to this article as recorded by  - Improved oxidation stability of carbon-coated Ni nanoparticles synthesized by one-step electrical wire explosion
Jun-Hyeok Lee, Byung-Hoon Kim, Gyoung-Ja Lee
Materials Chemistry and Physics.2022; 276: 125410. CrossRef - Fabrication of Ni-free Fe-based Alloy Nano Powder by Pulsed Wire Evaporation in Liquid: Part I. Effect of Wire Diameter and Applied Voltage
Ho-Jin Ryu, Yong-Heui Lee, Kwang-Ug Son, Young-Min Kong, Jin-Chun Kim, Byoung-Kee Kim, Jung-Yeul Yun
Journal of Korean Powder Metallurgy Institute.2011; 18(2): 105. CrossRef - A Study on Thermal Properties of Ethylene Glycol Containing Copper Oxide Nanoparticles
Chang-Kyu Kim, Gyoung-Ja Lee, Chang-Kyu Rhee
Journal of Korean Powder Metallurgy Institute.2010; 17(4): 276. CrossRef - Synthesis and Characterization of Cu Nanofluid Prepared by Pulsed Wire Evaporation Method
Chang-Kyu Kim, Gyoung-Ja Lee, Chang-Kyu Rhee
Journal of Korean Powder Metallurgy Institute.2010; 17(4): 270. CrossRef - Synthesis of Core/shell Structured Ag/C Nano Particles and Properties on Annealing Conditions
S.H. Jun, Y.R. Uhm, C.K. Rhee
Journal of Korean Powder Metallurgy Institute.2010; 17(4): 295. CrossRef - Synthesis and Characterization of Glold Nanofluid Prepared by the Solution Plasma Processing
Yong-Kang Heo, Sang-Yul Lee
Journal of Korean Powder Metallurgy Institute.2010; 17(4): 342. CrossRef
- Study of Mechanically Alloyed Nano Cu-Fe Particles With a Hetero-Structure
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Y.R. Uhm, H.M. Lee, C.K. Rhee
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J Korean Powder Metall Inst. 2007;14(2):97-100.
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DOI: https://doi.org/10.4150/KPMI.2007.14.2.097
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- The magnetic alloys of Cu-Fe (Cu_50Fe_50,;Cu_80Fe_20;and;Cu_90Fe_10) were prepared by a mechanical alloying method and their structural and magnetic behaviors were examined by X-ray diffraction and Mossbauer spectra. The magnetization curves did not distinctly show the saturation at 70 kOe for the concentrated alloys of Cu_80Fe_20;and;Cu_90Fe_10. The Mossbauer spectrum of Cu_80Fe_20 at room temperature shows one Lorentzian line of the paramagnetic phase, whereas the Mossbauer spectrum of Cu_90Fe_10 consists of sextet Lorentzian line at room temperature and a centered doublet line. The Mossbauer spectra of Cu_90Fe_10 measured in the temperature ranges from 13 to 295 K, implies that Cu_90Fe_10 to consists of two magnetic phases. One superimposed sextet corresponds to the ferromagnetic iron in Cu and the other one indicates the superparamagnetic iron rich phase.
- Room-temperature Ferromagnetism in Fe-doped Reduced TiO2-δ
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H.M. Lee, C.S. Kim, Y.R. Uhm, C.K. Rhee
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J Korean Powder Metall Inst. 2006;13(6):401-407.
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DOI: https://doi.org/10.4150/KPMI.2006.13.6.401
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- Effects of oxygen deficiency on the room temperature ferromagnetism in Fe-doped reduced TiO_2 have been investigated by comparing the air-annealed Ti_0.97Fe_0.03O_2 compound with secondly post-annealed one in vacuum ambience. The air-annealed sample showed a paramagnetic behavior at room temperature. However, when the sample was further annealed in vacuum, a strongly enhanced ferromagnetic behavior was observed at same temperature. M"ossbauer spectra of air-annealed sample at 295K showed a single doublet of Fe3+
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