Heat capacity of nanocrystalline bismuth ferrite

• Published in: High temperature Vol. 53; no. 4; pp. 601 - 604
• Main Authors: Kallaev, S. N., Omarov, Z. M., Palchaev, D. K., Rabadanov, M. Kh, Murlieva, Zh. Kh, Faradzheva, M. P., Sadykov, S. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.07.2015
• Subjects: Atoms and Molecules in Strong Fields; Classical and Continuum Physics; Industrial Chemistry/Chemical Engineering; Laser Matter Interaction; Materials Science; Physical Chemistry; Physics; Physics and Astronomy; Short Communications; Bismuth; Ferrite; Tempera Ture Range; Heat Capacity; Excess Heat Capacity
• ISSN: 0018-151X; 1608-3156
• DOI: 10.1134/S0018151X1504015X

The heat capacity of the nanocrystalline multiferroic BiFeO 3 was studied in a wide temperature interval of 150–800 K. It was found that the heat capacity nanocrystalline of bismuth ferrite in the temperature range of 350–570 K is noticeably larger than that of the microcrystalline sample. It was shown that the temperature dependence of the excess heat capacity is due to the manifestation of the Schottky effect for the three-level states appearing as a result of the structural distortions. The anomaly of the heat capacity typical for the phase transition, the manifestation of which depends on crystallite sizes, was discovered in the temperature range of T ≈ 720–750 K.