Crystal Structure, Magnetic Properties and Thermal Behavior of BaFe _11.9 In _0.1 O ₁₉ Ferrite

Herein, the crystal structure, surface morphology, and magnetic and thermal properties of the BaFe 11.9 In 0.1 O 19 ‐substituted M‐type hexaferrite are investigated. This solid solution is fabricated using “two‐step” topotactic reactions. It is determined through the X‐ray diffraction method that the crystal structure of this solid solution under normal conditions has hexagonal symmetry with P6 3 /mmc space group (No. 194) with the unit cell parameters a = 5.8992(1) Å and c = 23.2275(7) Å. It is determined by the scanning electron microscope (SEM) researches that the average size of the grains is = 6 μm. It is determined by the vibration magnetometry that the ferrimagnet–paramagnet phase transition happens at around T C = 420 °C. Using differential scanning calorimetry (DSC), it is found that air and water molecules leave the sample surface up to 420 °C and the resulting oxygen anions appearing as a result of a solvothermal reaction fill the oxygen vacancies in the crystal structure at high temperatures up to 800 °C. The thermal transitions repeated in the high temperatures are established. The oxidation behavior of this compound is determined from thermogravimetric analysis (TGA) in a wide temperature range.