Synthesis of High-Coercive Epsilon-Iron Oxide Nanoparticles for Biomedical Applications

• Main Authors: Testov, Dmitry O., Gareev, Kamil G., Khmelnitskiy, Ivan K., Kosterov, Andrei, Maraeva, Evgenia V., Klimtsova, Irina V.
• Format: Conference Proceeding
• Language: English
• Subjects: Coercive force; epsilon-iron oxide; Magnetic hysteresis; magnetic properties; Magnetic separation; Nanoparticles; Silicon compounds; Toxicology; X-ray diffraction
• ISSN: 2376-6565
• DOI: 10.1109/ElConRus54750.2022.9755783

Epsilon-iron oxide (ε-Fe2O3) is one of Fe2O3 polymorphs existing in the narrow grainsize range (8-30 nm). Epsilon-iron oxide has higher coercive force compared to the traditional hard magnetic materials (e.g. Sm-Co or Nd-Fe-B alloys). At the same time, it does not contain rare-earth elements. Nanoparticles of ε-Fe2O3 can be used in biomedicine as magnetic hyperthermia agents with high specific absorption rate due to hysteresis losses, and low toxicity. In this work, ε-Fe2O3 nanoparticles have been prepared using silica gel matrices with specific surface area of about 70-500 m 2 /g. The matrices were impregnated with iron (II) sulfate, dried in air at 110 °С for 24 h and finally calcined in air at 900 °С for 4 h. According to X-ray diffraction, the obtained samples contain 39-73 weight % of ε-Fe2O3, and show coercivity of up to 12 kOe at room temperature.