Formation of carbides in the interaction of Fe and Al with fullerenes at high pressures and high temperatures

• Published in: Materials letters 2021-09, Vol.299, p.130093, Article 130093
• Main Authors: Blanter, Mikhail S., Borisova, Polina A., Brazhkin, Vadim V., Sviridova, Tatiana A., Filonenko, Vladimir P., Kondratev, Oleg A.
• Format: Article
• Language: English
• Subjects: Aluminum carbide; Carbides; Cementite; Crystal structure; Crystallinity; Fullerenes; Fullerenes C70 and C60; Graphite; High pressure; High temperature; Iron carbides; Materials science; Phase transformations; Phase transitions; Transformation temperature; X-ray diffraction
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2021.130093

[Display omitted] •Phase transformations of fullerenes C60 and C70 with Al or Fe.•Formation of carbides at high temperatures and pressures.•Carbides are not formed when metals interact with crystalline fullerenes.•Carbides are formed by metal interaction with amorphous graphite. Phase transformations in crystalline and amorphous fullerenes C60 and C70 with additions of Fe or Al (7 at% each) at high pressures of 2 and 8 GPa and high temperatures of 500–1100 °C have been investigated by X-ray diffraction. Two groups of phase transformations were found: amorphous or crystalline fullerenes into disoriented graphite and the formation of carbides Fe3C, Fe7C3, or Al4C3. It was shown that the introduction of Fe or Al significantly increases the transformation temperature of crystalline fullerene and does not affect the transformation of amorphous fullerenes. Carbides in most of the studied fullerene – metal systems are not formed upon the interaction of Fe or Al with crystalline fullerenes, but are formed only upon interaction with disordered graphite. The results obtained are explained on the basis of a comparison of the interaction of metal atoms with fullerene molecules and with individual carbon atoms.