Yang Liya, Huang Houbing, Xi Zengzhe, Zheng Limei, Xu Shiqi, Tian Gang, Zhai Yuzhi, Guo Feifei, Kong Lingping, Wang Yonggang, Lü Weiming, Yuan Long, Zhao Minglei, Zheng Haiwu, Liu Gang
School of Physics, State Key Laboratory of Crystal Materials, Shandong University, 250100, Jinan, China.
International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, School of Physics and Electronics, Henan University, 475004, Kaifeng, China.
Nat Commun. 2022 May 4;13(1):2444. doi: 10.1038/s41467-022-29962-6.
A large coercive field (E) and ultrahigh piezoelectricity are essential for ferroelectrics used in high-drive electromechanical applications. The discovery of relaxor-PbTiO crystals is a recent breakthrough; they currently afford the highest piezoelectricity, but usually with a low E. Such performance deterioration occurs because high piezoelectricity is interlinked with an easy polarization rotation, subsequently favoring a dipole switch under small fields. Therefore, the search for ferroelectrics with both a large E and ultrahigh piezoelectricity has become an imminent challenge. Herein, ternary Pb(ScNb)O-Pb(MgNb)O-PbTiO crystals are reported, wherein the dispersed local heterogeneity comprises abundant tetragonal phases, affording a E of 8.2 kV/cm (greater than that of Pb(MgNb)O-PbTiO by a factor of three) and ultrahigh piezoelectricity (d = 2630 pC/N; d = 490 pC/N). The observed E enhancement is the largest reported for ultrahigh-piezoelectric materials, providing a simple, practical, and universal route for improving functionalities in ferroelectrics with an atomic-level understanding.
对于用于高驱动机电应用的铁电体而言，大矫顽场（E）和超高压电性至关重要。弛豫铁电体-PbTiO3晶体的发现是近期的一项突破；它们目前具有最高的压电性，但通常矫顽场较低。出现这种性能劣化是因为高压电性与易于极化旋转相关联，进而有利于在小电场下的偶极开关。因此，寻找兼具大矫顽场和超高压电性的铁电体已成为一项紧迫的挑战。在此，报道了三元Pb(ScNb)O3-Pb(MgNb)O3-PbTiO3晶体，其中分散的局部不均匀性包含丰富的四方相，其矫顽场为8.2 kV/cm（比Pb(MgNb)O3-PbTiO3大三倍）且具有超高压电性（d33 = 2630 pC/N；d31 = 490 pC/N）。观察到的矫顽场增强是超高压电材料中报道的最大增强，为在原子层面理解的基础上改善铁电体功能提供了一条简单、实用且通用的途径。
