Enhanced bipolar fatigue resistance by few oxygen vacancies of PZN-PNN-PZT ceramics near MPB

• Published in: Journal of alloys and compounds 2023-12, Vol.968, p.172077, Article 172077
• Main Authors: Shi, Ying, Du, Wentong, Man, Zhenyong, Ruan, Xuezheng, Zheng, Liaoying, Zeng, Huarong, Li, Guorong
• Format: Article
• Language: English
• Subjects: Bipolar fatigue; Defect dipoles; MPB; Oxygen vacancy; PNN-PZT
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.172077

The bipolar fatigue behavior for Mn-doped PZN-PNN-PZT ceramics with composition near the MPB region was investigated at both 0.6 Ec and 2 Ec (where Ec is a coercive field). It was found that fatigue behavior depends on both the Mn doping content (or oxygen vacancies and the amplitude of the applied electric fields. Compared to no Mn doping ceramics, enhanced bipolar fatigue resistance was observed in 0.1 wt% Mn doping samples by nearly no variation of remnant polarization up to 106 cycles. The enhanced fatigue behavior is proposed to the weak pinning effect of few oxygen vacancies on domain walls, which hinders the microcrack propagation and stabilizes the domain structure. As Mn doping content increased, rich oxygen vacancies exist in ceramics, and the remnant polarization deteriorated due to the severe pinning effect of defect dipoles. Besides, different fatigue behaviors at 0.6 Ec and 2 Ec indicate that fatigue behavior can be controlled by the orientation of defect dipoles under repeated fatigue cycling. •Few oxygen vacancies can enhance the bipolar fatigue resistance of ceramics.•Oxygen vacancy and defect dipoles dominate at different Mn-doping content.•Defect dipoles show different behavior under different amplitudes of electric fields.•The unlocked defect dipoles will be locked again after the “wake-up” process at 2 EC.