Polaron-mediated transport and relaxation phenomena in the lead zinc niobate (PZN) modified bismuth ferrite solid solution

Abstract

To investigate the dielectric and conductivity properties of PZN modified BF solid solution high temperature mixed oxide technique is employed. The material is subjected to analysis using XRD, SEM, and impedance spectroscopy. A polycrystalline PZN-BF sample with an average crystallite size of 63.3 nm has been formed. The scanning electron micrographs show that the grains and grain boundaries are distributed suitably. dielectric characteristics of the 0.1PZN-0.9BF compound are studied at frequencies ranging from 1 kHz to 1 MHz and temperatures ranging from ambient temperature to 400 °C. The confined mobility of charge carriers causes nearly continuous loss (NCL) behavior at low temperatures (<200 °C). High-temperature relaxation resulting from charge carrier hopping induces maximum loss and elevated conductivity. Rendering to the Overlapping Large Polaron Tunnelling (OLPT) model of conductivity, the transport mechanism in this modified BiFeO3 (BF) compound is facilitated by the short-range hopping of polarons. The NTCR behavior from Arrhenius plot of ac conductivity and temperature independent conductivity relaxation from loss modulus (M'') analysis are demonstrated. Sensors, actuators, and optoelectronic devices can benefit from the PZN-modified BF compound's electrical and dielectric characteristics, which have been studied in detail.