The fabrication and electrocaloric effect of bimodal-grain structure (Ba0.60Sr0.40)TiO3 using the induced abnormal grain growth method

Abstract

Bimodal-grain structure (Ba0.6Sr0.4)TiO3 ceramics had been prepared using induced abnormal grain growth method (IAGG). Two grain size distributions, between 10 ∼ 20 μm and 100 ∼ 300 μm, were found during the sintering temperature of 1250 ∼ 1350°C. Our results suggested that the ultra-large grain exhibited the high dielectric and ferroelectric properties comparable to the single crystal. At the same time, the fine-grain caused a phase diffusion transition at the Curie temperature about 20°C. The direct measured electrocaloric effect showed that the best performance is achieved with ΔT of 0.6 K, and ΔS of 1.02 J kg-1K-1 near room temperature and electric field strength of 2 MV/m.