Realizing high low-electric-field energy storage performance in AgNbO3 ceramics by introducing relaxor behaviour

作者：Kai Han, Nengneng Luo, Shuaifei Mao, Fangping Zhuo, Xiyong Chen, Laijun Liu, Changzheng Hu, Huanfu Zhou, Xinpeng Wang, Yuezhou Wei · 发表于：Journal of Materiomics · 年份：2019 · DOI：10.1016/j.jmat.2019.07.006 · 被引用次数：126 · 研究领域：Ferroelectric and Piezoelectric Materials、Dielectric materials and actuators、Multiferroics and related materials

Both sustainable development in environment and safety of high-power systems require to develop a novel lead-free dielectric capacitor with high energy density (Wrec) at low applied electric field. In this work, a remarkably high Wrec of 2.9 J/cm3 accompanying with energy storage efficiency of 56% was achieved in Ag0.9Sr0.05NbO3 ceramic at a low applied electric field of 190 kV/cm, by improving anti-ferroelectricity and introducing relaxor behaviour. The improved anti-ferroelectric stability was attributed to the decreased tolerance factor and average electronegativity difference, while the relaxor behaviour was associated with the increased disordered local structure by Sr-doping. Moreover, the Ag0.9Sr0.05NbO3 ceramics also exhibited outstanding temperature stability in energy density with small variation less than 5% over 20–140 °C. The results indicate that the Ag0.9Sr0.05NbO3 ceramic is a promising candidate for low-electric-field driving capacitors.