Structural and electrical features of lead-free ferroelectric: Li_1/2Bi_1/2TiO₃

Abstract

In this communication, the detailed analysis of structural (including microstructural) and electrical (dielectric, impedance, conductivity, and modulus) features of a perovskite Li_1/2Bi_1/2TiO₃ are reported. The compound is prepared by a high-temperature solid-state reaction technique. From X-ray diffraction, the crystal structure is fully satisfied with the monoclinic system of the material. Both dielectric permittivity and loss tangent of the pellet sample is scanned and analyzed in extensive temperatures (30–500 °C) and frequencies (100 Hz–1 MHz). Dielectric anomaly is detected at a particular temperature of 109 °C that may be associated with the ferroelectric-paraelectric phase transition. Through the Nyquist diagram, the presence of grains and grain boundary effect in the compound is detected. The observed non-Debye type of relaxation feature is confirmed through the complex impedance spectroscopy. Impedance analysis suggests that the grain resistance reduces with the rise of operating temperature, showing the negative temperature coefficient of resistance (NTCR) nature. Also, the non-Debye type of relaxation phenomenon is established from the modulus spectroscopy analysis. The significant result infers that this compound may be utilized for different high-temperature applications.