High-temperature electrical properties of LaFe_1-xTi_xO₃ (x = 0.4, 0.5, 0.6)

We report herein the high-temperature electrical properties of perovskite LaFe_1-xTi_x,O₃ with x = 0.4, 0.5, 0.6. All samples were synthesized by using the sol-gel method, and the electrical properties were investigated by using impedance spectroscopy in the frequency range of 100 Hz-1 MHz and at temperatures ranging from 348 to 548 K. Nyquist plots show a decrease in impedance with decreasing Ti content and the diameter of the Nyquist plot impedance semicircle decreases with increasing temperature. The dielectric constant increases with increasing temperature until reaches 10⁵ at 548 K. In addition, the dielectric relaxation phenomenon appears at all temperatures. Finally, we used scanning electron microscopy to study morphology, grain size, and grain distribution of these materials. The average grain size is 360-370 nm and increases with increasing Ti content.