Synthesis of multiferroic DyFeO₃ nanoparticles and study of their magnetic properties

We synthesized DyFeO₃ nanoparticles having sizes of 53, 65, 87, and 93 nm by mixing aqueous solutions of metal chlorides and sodium hydroxide. We found that the particle size increased with the annealing temperature. The magnetization of each particle was measured by using a SQUID magnetometer under a H = ±50 kOe magnetic field at temperatures ranging from 5 to 300 K. Samples having sizes of 65, 87, and 93 nm were observed to have a spin arrangement transition temperature T_N of around 55 K. The magnetic properties of the particles changed drastically depending on their size. For example, the sample having a size of 53 nm did not have a T_N value.