TY  - JOUR
AU  - Ma, Li
AU  - Chen, Zhenpei
AU  - Luo, Gengguang
AU  - Che, Zhiyi
AU  - Xu, Chao
AU  - Shan, Dongliang
AU  - Cen, Zhenyong
AU  - Feng, Qin
AU  - Chen, Xiyong
AU  - Fujita, Toyohisa
AU  - Zhu, Ye
AU  - Liu, Yunya
AU  - Li, Jing-Feng
AU  - Zhang, Shujun
AU  - Luo, Nengneng
PY  - 2024
TI  - High energy storage density in NaNbO3 antiferroelectrics with double hysteresis loop
JO  - Journal of Materiomics
SN  - 2352-8478
SP  - 1026
EP  - 1035
VL  - 10
IS  - 5
AB  - Antiferroelectrics (AFEs) possess great potential for high performance dielectric capacitors, due to their distinct double hysteresis loop with high maximum polarization and low remnant polarization. However, the well-known NaNbO3 lead-free antiferroelectric (AFE) ceramic usually exhibits square-like P–E loop related to the irreversible AFE P phase to ferroelectric (FE) Q phase transition, yielding low recoverable energy storage density (Wrec). Herein, significantly improved Wrec up to 3.3 J/cm3 with good energy storage efficiency (η) of 42.4% was achieved in Na0.7Ag0.3Nb0.7Ta0.3O3 (30Ag30Ta) ceramic with well-defined double P–E loop, by tailoring the A-site electronegativity with Ag+ and B-site polarizability with Ta5+. The Transmission Electron Microscope, Piezoresponse Force Microscope and in-situ Raman spectra results verified a good reversibility between AFE P phase and high-field-induced FE Q phase. The improved stability of AFE P phase, being responsible for the double P–E loop and improved Wrec, was attributed to the decreased octahedral tilting angles and cation displacements. This mechanism was revealed by synchrotron X-ray diffraction and Scanning Transmission Electron microscope. This work provides a good paradigm for achieving double P–E loop and high energy storage density in NaNbO3-based ceramics.
UR  - https://doi.org/10.1016/j.jmat.2023.11.003
DO  - 10.1016/j.jmat.2023.11.003