Dielectric anomaly in the microwave region and exchange bias effect in LaFeO3 nanoparticles at room temperature

LaFeO3 nanoparticles sample with an average size of 24.87?nm was synthesized by hydrothermal-assisted co-precipitation method. The structure refinement of the sample by using the rietveld method indicates that the coexistence of orthorhombic (Pbnm) and rhombohedral (R3c) phases which conformed by Fourier transform infrared (FTIR). By using UV-Vis diffuse reflectance spectrum, LaFeO3 nanoparticles have two band gap energies of 2.59 and 2.12?eV. The dielectric constant (?) of the sample in the microwave region exhibited an anomalous phenomenon at room temperature. Magnetic hysteresis loops (M-H) of the sample exhibits weak ferromagnetism and an antiferromagnetic order. Additionally, an exchange bias effect has been observed in this sample at room temperature.