Correlation between volatility of rare-earth metals and encapsulation of their carbides in carbon nanocapsules

Journal Article · Thu Jul 07 00:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100078a008· OSTI ID:7164607

Saito, Yahachi; Okuda, Mitsumasa; Yoshikawa, Tadanobu ^[1]; Kasuya, Atsuo; Nishina, Yuichiro ^[2]

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1. Mie Univ., Tsu (Japan)
2. Tohoku Univ., Sendai (Japan)

Encapsulation of metals in multilayered graphitic capsules has been studied for all the rare-earth elements (Sc, Y, and Ln = La, Ce, ..., Lu) excluding Pm by using electric arc discharge. Electron microscopy and X-ray diffraction of carbonaceous products revealed that most of rare-earth metals (Sc, Y, La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, and Lu) were encapsulated in the form of carbides, but the others, Sm, Eu, and Yb, were not. The metals in the former group that were encapsulated had vapor pressures definitely lower than those in the latter group. In the case of thulium (Tm), whose vapor pressure is intermediate between the two groups, only a trace amount of encapsulated carbide was formed. Correlation of volatility of metals with encapsulation was clearly found, suggesting that the volatility of a metal plays an important role in a process of the metal encapsulation. 25 refs., 4 figs., 1 tab.

• OSTI ID: 7164607
• Journal Information: Journal of Physical Chemistry; (United States), Vol. 98:27; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBIDES
ENCAPSULATION
RARE EARTH COMPOUNDS
RARE EARTHS
VOLATILITY
ELECTRIC ARCS
FULLERENES
GRAPHITE
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
CARBON
CARBON COMPOUNDS
COHERENT SCATTERING
CURRENTS
DIFFRACTION
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
ELECTRON MICROSCOPY
ELEMENTAL MINERALS
ELEMENTS
METALS
MICROSCOPY
MINERALS
NONMETALS
SCATTERING
400702* - Radiochemistry & Nuclear Chemistry- Properties of Radioactive Materials
400201 - Chemical & Physicochemical Properties
400102 - Chemical & Spectral Procedures