Enhanced electrocaloric effect at room temperature in Mn2+ doped lead-free (BaSr)TiO3 ceramics via a direct measurement
barium strontium titanate ceramics, permittivity, dielectric loss, electrocaloric effect, electrocaloric strength
(Ba1−xSrx)(MnyTi1−y)O3 (BSMT) ceramics with x = 35, 40 mol% and y = 0, 0.1, 0.2, 0.3, 0.4, 0.5 mol% were prepared using a conventional solid-state reaction approach. The dielectric and ferroelectric properties were characterized using impedance analysis and polarization–electric field (P–E) hysteresis loop measurements, respectively. The adiabatic temperature drop was directly measured using a thermocouple when the applied electric field was removed. The results indicate that high permittivity and low dielectric losses were obtained by doping 0.1–0.4 mol% of manganese ions in (BaSr)TiO3 (BST) specimens. A maximum electrocaloric effect (ECE) of 2.75 K in temperature change with electrocaloric strength of 0.55 K·(MV/m)–1 was directly obtained at ~21 ℃ and 50 kV/cm in Ba0.6Sr0.4Mn0.001Ti0.999O3 sample, offering a promising ECE material for practical refrigeration devices working at room temperature.
Tsinghua University Press
Xiang NIU, Xiaodong JIAN, Xianyi CHEN, Haoxuan LI, Wei LIANG, Yingbang YAO, Tao TAO, Bo LIANG, Sheng-Guo LU. Enhanced electrocaloric effect at room temperature in Mn2+ doped lead-free (BaSr)TiO3 ceramics via a direct measurement. Journal of Advanced Ceramics 2021, 10(3): 482-492.