This paper presents a systematic exploration of modifying the electrocaloric effect (ECE) in BaTiO3 ceramics by rare-earth substitution (Ba0.94R0.04TiO3, R = La, Ce, Nd, Sm, Eu, Gd, Dy, Er). All samples exhibit a dense microstructure after sintering in the temperature range of 1350-1450 degrees C, and they exhibit a high resistivity of similar to 10(11) Omega cm except for Er doped samples due to the amphoteric incorporation of Er. The rare-earth doping changes the lattice symmetry where the tetragonal distortion enhances with the decrease in the rare-earth ionic radius. Accordingly, the ferroelectric and ECE properties are modified and the first-order phase transition is diffused. The Curie temperature and latent heat increases, and the polarization intensity is strengthened with the decrease of the doping ionic radius, while the peak of ECE Delta T widens and shifts to a higher temperature. The samples show a large ECE value of similar to 0.35 K m MV-1 over a wide temperature range from room temperature to 140 degrees C, which provides a series of top-level ECE materials.
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机译：本文提出了通过稀土替代（Ba0.94R0.04TiO3，R = La，Ce，Nd，Sm，Eu，Gd，Dy，Er）改变BaTiO3陶瓷的电热效应（ECE）的系统探索。所有样品在1350-1450摄氏度的温度范围内烧结后均表现出致密的微观结构，并且由于两性掺入Er，除Er掺杂的样品外，它们均具有类似于10（11）Ωcm的高电阻率。稀土掺杂改变了晶格对称性，其中四方晶形畸变随着稀土离子半径的减小而增强。因此，铁电和ECE特性被修改，一阶相变被扩散。居里温度和潜热增加，并且极化强度随着掺杂离子半径的减小而增强，而ECEδT的峰变宽并移向更高的温度。在从室温到140摄氏度的宽温度范围内，样品显示出的大ECE值类似于0.35 K m MV-1，这提供了一系列顶级ECE材料。
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