Structure, magnetic, and dielectric properties of Ti-doped LaFeO3 ceramics synthesized by polymer pyrolysis method

Perovskite Ti-doped LaFeO3 (LaFe1-xTixO3,x= 0, 0.1, and 0.2) nanoparticles synthesized by the polymer pyrolysis method were investigated. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray absorption near edge spectroscopy (XANES), and vibrating sample magnetometry (VSM) were used to characterize phase, morphology, valence states and magnetic properties of the samples. The samples had a phase of the orthorhombic structure with crystallite sizes of 25 +/- 2-47 +/- 2 nm for nanoparticles, while ceramic samples had the grain sizes of 0.9 +/- 0.3-6.0 +/- 2.3 mu m. The result of XANES spectra showed that the Fe3+/Fe4+ and Ti4+ exist in the samples. The weak ferromagnetic behavior at room temperature is observed for all LaFe1-xTixO3 samples with a maximum magnetization of 032 emu/g for x= 0.2. Additionally, larger hysteresis loops induced significantly in ceramic samples with no saturation up to 10 kOe. The dielectric properties as a function of frequency at low temperatures suggest the presence of polarization in the samples due to the electron hopping between Fe3+ and Fe4+ ions. (C) 2015 Elsevier Ltd. All rights reserved.