Crystallite size dependence on electrical properties of LaFeO3.0.1Fe3O4 nanocomposite material

摘要

LaFeO3.O.1Fe3O4 nanocomposite was prepared by sintering method. LaFeO3 was synthesized by the sol-gel method and mixed with Fe3O4. The mixture was pressed and then sintered at 1300°C for 1 h resulting nanocomposite. After that, LaFeO3.0.1Fe3O4 nanocomposite was annealed at temperatures of 1000°C, 1100°C, and 1200°C for 12 h. Structural analysis by using X-ray diffraction (XRD) confirm the double phase of LaFeO3 and Fe3O4. The crystallite sizes calculated by using Scherrer's formula are in the range of 30-60 nm. By using impedance spectroscopy method, the electrical properties were evaluated as functions of frequency (1 kHz-1 MHz) and temperature (RT-373 K). Electrical properties were represented in Nyquist plot and Bode plot as a function of temperature. Bode plot of Z" vs f shows that relaxation peaks shift to the higher frequency. From the plot of In τ vs 1/T, the activation energy was calculated.