Phase engineering in NaNbO3 antiferroelectrics for high energy storage density
Zhengu Chen, Shuaifei Mao, Li Ma, Gengguang Luo, Qin Feng, Zhenyong Cen, Toyohisa Fujita, Xiuning Peng, Laijun Liu, Huanfu Zhou, Changzheng Hu, Nengneng Luo
Abstract
The NaNbO3 antiferroelectrics have been considered as a potential candidate for dielectric capacitors applications. However, the high-electric-field-unstable antiferroelectric phase resulted in low energy storage density and efficiency. Herein, good energy storage properties were realized in (1-x)NaNbO3-xNaTaO3 ceramics, by building a new phase boundary. As a result, a high recoverable energy density (Wrec) of 2.2 J/cm3 and efficiency (η) of 80.1% were achieved in 0.50NaNbO3-0.50NaTaO3 ceramic at 300 kV/cm. The excellent energy storage performance originates from an antiferroelectric-paraelectric phase boundary with simultaneously high polarization and low hysteresis, by tailoring the ratio of antiferroelectric and paraelectric phases. Moreover, the 0.50NaNbO3-0.50NaTaO3 ceramic also exhibited good temperature and frequency stability, together with excellent charge-discharge performance. The results pave a good way of designing new NaNbO3-based antiferroelectrics with good energy storage performance.