Influence of synthesis method on the structural, optical and magnetic properties of BiFeO_3-ZnFe_2O_4 nanocomposites

摘要

In this study, single-phase polycrystalline (1 - x)BiFeO3-xZnFe(2)O(4) (BFO-ZFO, x = 0, 0.5, 1) nanocomposites have been synthesized by sol-gel (SG) and hydrothermal (HT) methods and the effect of synthesis method on structural, optical and magnetic properties of all products have been studied. The as-prepared samples were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) images, diffuse reflectance UV-Vis spectroscopy (DRS) and vibrating sample magnetometer (VSM). XRD patterns reveal the rhombohedrally-distorted perovskite phase of bismuth ferrite and the cubic spinel phase of zinc ferrite. The crystallite size and micro-strain of nanograins were calculated using Scherrer formula and Williamson-Hall analysis. FTIR analysis confirms ferrite phases and the functional groups in the wavenumber range of 400-4000 cm(-1) were observed. SEM analysis confirmed the agglomerated nature of the particles with continuous grain growth in all directions. Magnetic hysteresis loops also showed the weak ferromagnetic behavior of BFO and paramagnetic (SG_ZFO) and superparamagnetic (HT_ZFO) behavior of zinc ferrite depending on their synthesis method at room temperature (RT). Remarkably, SG_BFO-ZFO nanocomposite also has a little more magnetization compared with pure BFO and ZFO nanoparticles. Finally, characteristic measurements indicated that the as-prepared nanoparticles, depending on their preparation route, behave differently.