Electrocaloric effect and pyroelectric energy harvesting in diffuse ferroelectric Ba(Ti1-xCex)O-3 ceramics
Electrocaloric effect and pyroelectric energy harvesting in diffuse ferroelectric Ba(Ti1-xCex)O-3 ceramics
复制标题
弥散铁电 Ba(Ti1-xCex)O-3 陶瓷中的电热效应和热释电能量收集
DOI：
10.1007/s10832-019-00183-6
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发表时间：
2019
影响因子：
1.7
通讯作者：
Chen X. M.
中科院分区：
文献类型：
--
作者：
Zhao Y.;Liu X. Q.;Wu S. Y.;Chen X. M.
本文采用标准的固态烧结工艺制备了Ba(Ti1-xCex) o3陶瓷。对晶体结构、介电性能、铁电性能和热电效应进行了精确的研究。Ce4+离子不能完全进入Ti4+的位置，因此产生了一些不纯的相。用Ce4+取代Ti4+增强了相变的扩散率。随着铈离子含量的增加，最大热释电系数减小，相应温度偏离介电峰值温度到更高温度的程度增大。绝热温度变化和等温熵变表现出与热释电系数相同的趋势。Ba(Ti0.9Ce0.1) o3陶瓷的绝热温度变化最大，为0.41 K，等温熵变化最大，为0.45 J/（kg·K）。绝热温度变化响应率为0.090 × 10−6K·m/V，等温熵变响应率为0.100 × 10−6J·m/（kg·K·V）。各组分的热释电系数绝对值随外加电场大小的增大而减小，最大热释电系数温度偏离介电峰温度向更高温度偏移。Ba(Ti0.9Ce0.1) o3陶瓷的热释电能密度最大，为0.14 J/cm3。
In the present work Ba(Ti1-xCex)O3ceramics are prepared through a standard solid-state sintering process. Crystal structures, dielectric properties, ferroelectric properties and electrocaloric effects are exactly studied. Ce4+ions cannot entirely enter the position of Ti4+, so some impure phases are generated. The diffusivity of phase transition is strengthened by substituting Ti4+with Ce4+cations. The maximal pyroelectric coefficient decreases, and the extent of corresponding temperature deviating from the dielectric peak temperature to higher temperature increases with increasing the content of cerium cations. The adiabatic temperature change and isothermal entropy change display the same tendency as that of the pyroelectric coefficient. The Ba(Ti0.9Ce0.1)O3ceramic shows the largest adiabatic temperature change of 0.41 K and the largest isothermal entropy change of 0.45 J/(kg·K) among the ceramics. Accordingly, the adiabatic temperature change responsivity is 0.090 × 10−6K·m/V, and the isothermal entropy change responsivity is 0.100 × 10−6J·m/(kg·K·V). For individual composition, the absolute value of pyroelectric coefficient decreases with increasing the magnitude of applied electric field, and the temperature of maximal pyroelectric coefficient deviates from the dielectric peak temperature shifts to higher temperature. Ba(Ti0.9Ce0.1)O3ceramics show the largest pyroelectric energy density of 0.14 J/cm3among all compositions.