Eur. Phys. J. B (2015) 88: 232
https://doi.org/10.1140/epjb/e2015-60445-2

Regular Article

Effect of sintering temperature and oxygen atmosphere on electrocaloric effect of BaTiO₃ ceramics^*

¹ National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083, P.R. China
² Key Laboratory of Environmental Fracture (MOE), Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, P.R. China

^a e-mail: baiy@mater.ustb.edu.cn

Received: 4 June 2015
Received in final form: 22 July 2015
Published online: 16 September 2015

Abstract

This paper demonstrates the effect of sintering parameters on the electrocaloric effect (ECE) in BaTiO₃ ferroelectric ceramics, especially the sintering temperature and atmosphere. The samples were prepared by solid-state reaction method. With the rise of sintering temperature from 1200 °C to 1350 °C, the grain size increases remarkably and the densification is improved. The 1350 °C sintered sample has better ferroelectricity and higher latent heat for ferroelectric-paraelectric phase transition than those of the 1200 °C sintered sample. Correspondingly, it exhibits much better ECE. If the sample is sintered in pure oxygen, instead of in air, all ferroelectricity, dielectric strength and ECE are further enhanced. The sample sintered at 1350 °C in oxygen exhibits an excellent ECE performance with ΔT_max = 1.37 K and ΔS_max = 1.75 J/kg K.