On the origin of grain size effects in Ba(Ti0.96Sn0.04)O3 perovskite ceramics
On the origin of grain size effects in Ba(Ti0.96Sn0.04)O3 perovskite ceramics
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DOI：
10.1016/j.jeurceramsoc.2019.01.041
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发表时间：
2019-06
影响因子：
5.7
通讯作者：
Y. Tan;G. Viola;V. Koval;Chuying Yu;A. Mahajan;Jialiang Zhang;Haibin Zhang;Xiaosong Zhou
中科院分区：
文献类型：
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作者：
Y. Tan;G. Viola;V. Koval;Chuying Yu;A. Mahajan;Jialiang Zhang;Haibin Zhang;Xiaosong Zhou
在过去的50年里，铁电陶瓷中的颗粒尺寸效应的研究引起了人们极大的兴趣。尽管已经提出了不同的理论模型来解释铁电材料的结构和性质随结构颗粒尺寸的变化，但其潜在的机制仍然存在争议。本文报道了Ba0.96Sn0.04)O_3(BTS)的晶体尺寸对其结构和物理性质的影响的研究结果。BTS是一种代表钙钛矿模型的铁电化合物，其中点缺陷、化学计量比不平衡和相变的影响通过化学替代来最小化。结果发现，不同的微观机制导致了BTS中观察到的不同的晶粒度依赖关系。细晶BTS陶瓷的高介电常数是由于高的磁畴壁密度和极性纳米区域；粗晶陶瓷的高d33是因为极化过程中高度的磁畴对准；中晶陶瓷的大电场感应应变是晶界约束和非180°磁畴和极性纳米区域的可逆重新取向的有利相互作用的结果。这些范例可作为通过控制晶粒度来优化铁电陶瓷特性的一般指导方针。
Over the last 50 years, the study of grain size effects in ferroelectric ceramics has attracted great research interest. Although different theoretical models have been proposed to account for the variation in structure and properties of ferroelectrics with respect to the size of structural grains, the underlying mechanisms are still under debate. Here, we report the results of a study on the influence of grain size on the structural and physical properties of Ba(Ti0.96Sn0.04)O3(BTS), a ferroelectric compound that represents a model perovskite system, where the effects of point defects, stoichiometry imbalance and phase transitions are minimized by chemical substitution. It was found that different microscopic mechanisms are responsible for the different grain size dependences observed in BTS. High permittivity is achieved in fine-grained BTS ceramics due to high domain wall density and polar nanoregions; high d33is obtained in coarse-grained ceramics due to a high degree of domain alignment during poling; large electric field-induced strain in intermediate-grained ceramics is an outcome of a favorable interplay between constraints from grain boundaries and reversible reorientation of non-180° domains and polar nanoregions. These paradigms can be regarded as general guidelines for the optimization of specific properties of ferroelectric ceramics through grain size control.