Impact of rare earth oxide on ZnFe₂O₄: structural, magnetic properties, and hyperthermia efficiency

Abstract

ZnFe2O4/Yb2O3 (ZF/Yb) and ZnFe2O4/Sm2O3 (ZF/Sm) were prepared by the sol-gel method. XRD pattern of sample ZF show a clear cubic spinel structure (space group fd-3m). The XRD confirmed the presence of ZF along with Yb in the ZF/Yb. In the case of ZF/Sm, the raw materials interact with each other and produce ZF alongside ZnO and SmFeO3. The SEM and TEM indicate that all compounds were at the nanoscale. The particle size for ZF is 19.6 nm, and those for ZF/Yb and ZF/SM are 29.5 nm and 30.7 nm, respectively. A vibrating sample magnetometer (VSM) confirmed the ferrimagnetic ordering of these samples. A distinct, potent, sweeping, and asymmetric line was observed in the X-band electron spin resonance (ESR) spectra of all samples. The VSM and ESR show that the internal interactions between ZF and rare earth oxides, as well as the particle size, play a role in the magnetic properties. The specific absorption rate (SAR) parameters showed that the temperature increased linearly with time, and in only 25 seconds, the temperature reached 45 °C for the ZF sample.