Structure, optical and magnetic properties of LaFeO3 nanoparticles prepared by polymerized complex method

This work reports the study the structure, optical and magnetic properties of LaFeO3 nanoparticles synthesized by the polymerized complex method. The LaFeO3 nanoparticles were successfully obtained from calcination of the precursor at different temperatures from 750 to 1,050 °C in air for 2 h. The calcined LaFeO3 nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–Visible spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge spectroscopy (XANES) and vibrating sample magnetometry. The XRD and TEM results showed that all LaFeO3 samples had a single phase nature with the orthorhombic structure. The estimated crystallite sizes were in the range of 44.5 ± 2.4–74.1 ± 4.9 nm. UV–Vis spectra showed strong UV and Vis absorption with small band gap energy. The valence states of Fe ions were in the Fe3+ and Fe4+ state, as confirmed by XPS and XANES results. The weak ferromagnetic behavior with specific saturation magnetization of 0.1 emu/g at 10 kOe was obtained for the small particle of 44.5 ± 2.4 nm. The uncompensated spins at the surface was proposed as playing a part in the magnetic properties of small sized LaFeO3.