Dielectric and electrical characterization of lead-free complex electronic ceramic: (Bi_1/2Li_1/2)(Zn_1/2W_1/2)O₃

A Lead-free complex perovskite compound of (Bi_1/2Li_1/2)(Zn_1/2W_1/2)O₃ has been synthesized by using high-temperature solid-state reaction technique. The structural, micro-structural, dielectric constant, tangent loss, electrical impedance, modulus, conductivity and polarization characteristics of the prepared compound have been studied over a wide range of temperature (150–500 °C) and frequency (1 kHz–1 MHz). The X-ray diffraction structural analysis reveals tetragonal structure of the compound with cell parameters; a = 10.6055 (36) Å, c = 13.8275 (36) Å, c/a = 1.3038 and volume V = 1555.27 Å³. The acquired room temperature scanning electron micrograph exhibits the homogeneous distribution of fibre-type of grains throughout the surface of specimen. The dielectric constant and tangent loss of the material at a frequency of 1 kHz are found to be 4000 and 11 respectively. The ac conductivity spectrum provides the information about the conduction mechanism and semiconducting nature of the compound. The impedance spectrum provides an insight into the contributions of grain and grain boundary effects in the resistive and capacitive characteristics of the materials. The frequency dependence of complex modulus analysis shows the presence of non-Debye type of relaxation behaviour in the material.