The electrocaloric effect of Ba1-xLaxTi0.9Sn0.1O3 ceramics with excellent temperature stability near room temperature. Issue 12 (15th June 2022)

• Record Type: Journal Article
• Authors: Xu, Ning; Liu, Qi; Sun, Zixiong; Ma, Jiahui; Luo, Yuxin; Pu, Yongping
• Is Part Of: Ceramics international. Volume 48:Issue 12(2022)
• Page Start: 16956
• Page End: 16966
• Publication Date: 2022-06-15
• Subjects: Electrocaloric effect -- Multiphase coexistence -- Diffuse phase transition -- Electrocaloric strength; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.02.250
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The Ba1- x La x Ti0.9 Sn0.1 O3 ceramics ( x = 0, 0.006, 0.007, 0.008) were prepared by the traditional solid-state reaction method. The influence of La 3+ on the phase, dielectric properties, ferroelectric properties, and electrocaloric effect (ECE) was analyzed in detail. The results of refinement show that all ceramics are multiphase coexistence at room temperature, including the cubic phase, the tetragonal phase, and the orthogonal phase. With the increase of La 3+, the polar phases decrease but the non-polar phase increases, which is the main reason for the decline in adiabatic temperature change ( ΔT ). The analysis of dielectric properties and ferroelectric properties demonstrate that the diffuse phase transition is strengthened by introducing La 3+ . It also means that polar nanoregions (PNRs) might be formed. Therefore, the temperature stability of the Ba1- x La x Ti0.9 Sn0.1 O3 ceramics in a wide temperature range near room temperature is improved. Simultaneously, the PNRs provide additional entropy to improve ECE. A higher ΔT = 0.88 K is obtained under 60 kV/cm for x = 0.007, which also possesses excellent temperature stability in the temperature range of 298 K–378 K. The doping of La 3+ also improves the electric field threshold of the electrocaloric strength ( ΔT max /ΔE ) and stabilizes the ΔT max /ΔE under a higher electric field, which is conducive to improving ECE under a higher electric field and providing another possible solution for promoting the practical application of ECE.