Preparation and properties of carbon-coated magnetic nanocrystallites.

摘要: Carbon-coated gadolinium carbide nanocrystallites are generated by a process based on the Kratschmer-Huffman carbon-arc method of preparing fullerenes, and novel magnetic-field-gradient separation technique is used to separate them. This nanocrystalline byproducts carbon arc prerequisite for many proposed applications these materials. While data presented pertain ${\mathrm{Gd}}_{2}$${\mathrm{C}}_{3}$, this generally applicable any paramagnetic or ferromagnetic compound. Structural characterization x-ray electron diffraction high-resolution transmission microscopy reveal presence single gadolinium-containing (${\mathrm{Gd}}_{2}$${\mathrm{C}}_{3}$) phase excess carbon. The exists as 10--50 nm spherical particles. SQUID magnetometry shows response attributed ${\mathrm{Gd}}^{3+}$ ions.