On the Synthesis of α-Fe2O3 Nanoparticles by the Method of Chemical Deposition to Obtain a Magnetically Hard Nd–Fe–B Alloy
Odiljon Abdurakhmonov, M. E. Alisultanov, Sherzod Abdurakhmonov, А. Г. Мурадова
Abstract
Nanoparticles of FeOOH are obtained by chemical precipitation with the use of FeCl 3 and NH 4 OH precipitant as precursors. The heat treatment of FeОOH yields α‑Fe 2 O 3 nanoparticles. Thermogravimetric analysis, differential scanning calorimetry, and X-ray phase analysis are performed to determine the thermal effects and phase transitions. The dehydration of FeOOH occurring during heat treatment is studied using infrared (IR) spectroscopy. The morphology of the obtained nanoparticles is studied using scanning and transmission electron microscopy. It is found that at a temperature of 540°С the complete formation of α‑Fe 2 O 3 from FeOOH occurs. The shape of the obtained α‑Fe 2 O 3 particles is close to ellipsoidal and the average nanoparticle diameter is 55 ± 11 nm.