Cation Distribution in the Composite Materials of the CaFe2O4--Fe2O3 Series

Knyazev, Yu. V.; Shishkina, N. N.; Bayukov, O. A.; Kirik, N. P.; Solovyov, L. A.; Zhizhaev, A. M.; Rabchevsky, E. V.; Anshits, A. G. Source: JOURNAL OF STRUCTURAL CHEMISTRY, 60 (5):763-771; 10.1134/S0022476619050081 MAY 2019

Structured composite materials CaFe2O4-α-Fe2O3 (α-Fe2O3 content is 2–82 wt.%) are obtained with the method of solid-phase synthesis at 1000 °C. The phase composition of the samples is studied using powder X-ray diffraction. It is shown that the content of CaFe2O4 and α-Fe2O3 phases changes linearly, depending on the composition of the starting material. The scanning electron microscopy data indicate the formation of a two-phase system α-Fe2O3-CaFe2O4. The Mössbauer spectroscopy data at room temperature testify the formation of cationic iron vacancies in the CaFe2O4 crystal structure in the absence of α-Fe2O3 structural defects. Cationic vacancies can be formed during the synthesis in the atmosphere of air.