Synthesis of Sc15C19 Crystallites Encapsulated in Carbon Nanocapsules by Arc Evaporation of Sc-C Composite

Abstract
Crystallites of scandium carbides nesting in multilayered, polyhedral graphitic cages (nanocapsules) were produced by evaporating a scandium-graphite composite rod by electric arc discharge in helium gas. The composite particles were characterized by analytical electron microscopy and X-ray diffraction. The encapsulated scandium carbide was identified to be Sc15C19, instead of dicarbide RC2 (R represents rare-earth elements) which was the form of carbide commonly found for other rare-earth elements entrapped in nanocapsules. The size of the capsules ranged from about 10 to 100 nm. Morphological features of the outer graphitic carbon, multilayered and polyhedral, were quite similar to those previously discovered for the capsules protecting RC2 (R=Y, La, Ce,…, Lu).