An oxygen defect-related dielectric relaxation behaviors of lead-free Ba(HfxTi1-x)O-3 ferroelectric ceramics
An oxygen defect-related dielectric relaxation behaviors of lead-free Ba(HfxTi1-x)O-3 ferroelectric ceramics
复制标题
无铅Ba(HfxTi1-x)O-3铁电陶瓷与氧缺陷相关的介电弛豫行为
DOI：
10.1088/1361-6463/aae3db
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Li Wen Hua
中科院分区：
文献类型：
--
作者：
Li Ming Ding;Tang Xin Gui;Zeng Si Ming;Jiang Yan Ping;Liu Qiu Xiang;Zhang Tian Fu;Li Wen Hua
首次系统研究了Ba（Hf xTi 1− x）O3铁电陶瓷的结构、介电、铁电性能和高温介电弛豫行为。结果表明，随着Hf含量的增加，Ba（HfxTi1 − x）O3陶瓷的T C降低，T O和T R增加。此外，在所有样品中观察到HTRB。从复阻抗和交流电导两个方面研究了HTRB的形成机理，发现HTRB的形成与氧空位的漂移有关。根据活化能的理论计算值，认为Ba（Hf xTi 1− x）O3体系中HTRB的产生是由于OVAs的短程跃迁，而电导的产生是由于双电离OVAs的长程移动.同时，用电子顺磁共振谱检测了BHTO陶瓷中的缺陷。结果表明，在g= 1.942处观察到OVA相关的缺陷信号。此外，氧退火还能显著抑制介电常数弛豫峰.这进一步证明了HTRB与氧的缺陷有关。
The structure, dielectric, ferroelectric property and high-temperature dielectric relaxation behaviors (HTRBs) were systematically studied for the first time in the Ba (Hf x Ti 1− x) O 3 ferroelectric ceramics. It was noted that the T C of the Ba (Hf x Ti 1− x) O 3 ceramics decreases, while T O and T R increases with the increase of Hf quantity. Furthermore, the HTRBs were observed in all samples. Mechanisms of HTRBs were studied from complex impedance and ac conductivity, exposing that it was concerned with the drifting of oxygen vacancies (OVAs). Based on the value of theoretical calculation for activation energy, it was concluded that the HTRBs were attributed to the short distance hopping of the OVAs and the conduction was ascribed to the long-range move of doubly-ionized OVAs in Ba (Hf x Ti 1− x) O 3 system. Meanwhile, electron paramagnetic resonance spectra were measured to detect the defects in BHTO ceramics. The results showed that the OVAs-related defect signals were observed at g= 1.942. In addition, the dielectric constant peak of relaxation could be significantly restrained by O 2 annealing. This further proved that the HTRBs being associated with the defect of oxygen.