【摘 要】
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(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 d
【机 构】
：
Guangdong Provincial Research Center on Smart Materials and Energy Conversion Devices,Guangdong Prov
论文部分内容阅读
(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.
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