Electrocaloric properties and caloric figure of merit in the ferroelectric solid solution BaZrO3–BaTiO3 (BZT). Issue 2 (February 2021)

• Record Type: Journal Article
• Authors: Novak, Nikola; Weyland, Florian; Jr, George A. Rossetti
• Is Part Of: Journal of the European Ceramic Society. Volume 41:Issue 2(2021)
• Page Start: 1280
• Page End: 1287
• Publication Date: 2021-02
• Subjects: Ferroelectrics -- Phase transition -- Electrocaloric effect -- Thermophysical properties -- Caloric cooling power; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2020.10.017
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: The impact of the differing phase change characteristics on the electrocaloric effect (ECE) and thermophysical properties of Ba(Zr x Ti1- x )O3 (BZT) were investigated. It is demonstrated that the ECE reduces strongly with increasing Zr concentration, from 1.25 K to 0.10 K. The strong reduction of ECE is associated with the vanishing of the latent heat as the nature of paraelectric to ferroelectric phase transition changes. Despite the second order nature of the phase transition, an enhanced electrocaloric responsivity, 0.225 × 10 −6 Km V -1, occurs at the triple point composition ( x = 0.13), where the stability fields of ferroelectric phases converge. The decreasing ECE and thermophysical properties with increasing Zr concentration result in a more than one order of magnitude reduction in a caloric figure of merit, from ∼3500 J m −1 s −1/2 to ∼200 J m −1 s −1/2 . The caloric figure of merit was used to compare the performance of other representative electrocaloric, magnetocaloric and mechanocaloric materials.