Effect of sintering temperature on the dielectric, ferroelectric and energy storage properties of SnO2-doped Bi 0. 5 (Na 0. 8 K 0. 2) 0. 5 TiO3 lead-free ceramics

Abstract

Sintered lead-free Bi0.5(Na0.8K0.2)0.5(Ti0.96Sn0.04)O3 ceramics (BNKTS) have been fabricated via a solid-state reaction. The effect of sintering temperature on the structural, morphological, dielectric, ferroelectric and energy storage properties of BNKTS ceramics was investigated, and it was found that the electrical properties of the synthesized ceramics increased with the increase in the sintering temperature, and the highest values were achieved at 1100°C. The ceramics sintered at the optimized temperature of 1100°C exhibited the best physical, dielectric, ferroelectric and energy storage properties, namely, high density (the relative density, ρ=5.88g.cm-3, approximate to 96.7% of the theoretical value), high densification factor (DF=0.93), high dielectric constant (ϵr=1215), low dielectric loss (tan=0.051), highest dielectric constant (ϵmax=4335), high remanent polarization (Pr=9.5μC.cm-2), high coercive field (Ec=14.3kV/cm), high energy storage density (0.12J/cm3), and high energy storage efficiency (41.7% at 46.3kV/cm).