Enhanced electrical properties by optimizing sintering temperature and dwell time in BiFe0.96Zn0.02Ti0.02O3 ceramics

Abstract

In this paper, effects of sintering temperature (T s) and dwell time (t d) on crystalline structure, microstructure and electrical properties (dielectric and ferroelectric) of BiFe0.96 Zn0.02Ti0.02O3 (BFZTO) ceramics synthesized by sol-gel method were investigated. The crystalline structure of BFZTO ceramics remained unchanged with different sintering conditions. The microstructure of BFZTO ceramics have an evident modification by changing sintering temperature and dwell time. With increasing T s or t d, grains of samples become larger. Because of the differences of sintering pross, The large grains and low porosity led to the alignment of the dipole, the low coercive field (E c of ca. 12 kv/cm), low leakage current density (10−1 μA/cm) and good remnant polarization (P r of ca. 1.2 μC/cm2) were achieved in BFZTO ceramics at T s = 800 °C, t d = 1 h. While the excessive T s or t d resulted in lower number of defect complexes, which had significant influence on ferroelectric properties. The work reported herein demonstrated that the porosity, grain size and the presence of defect complexes have a big part in determining ferroelectric properties of BFZTO ceramics.