Lead‐based ferroelectric materials are extensively employed in industrial applications and everyday life due to their excellent ferroelectric and piezoelectric performance. Pb(Ni_1/3Nb_2/3)O₃‐PbTiO₃ (PNN‐PT) is a typical binary relaxor ferroelectric system, whose refined structure and piezoelectric properties have not been systematically investigated. In this study, evolution of electric field‐based crystal structure and variation of ferroelectric, piezoelectric, as well as dielectric properties with composition and temperature of (1 − x)PNN‐xPT (0.32 ≤ x ≤ 0.36) ceramics were studied in full detail. The optimal performance is obtained at 0.66PNN‐0.34PT with maximum piezoelectric coefficient d₃₃ of 560 pC/N and large dielectric constant of 28 684. In situ high‐energy synchrotron diffraction was employed to determine structural origins of enhanced properties of 0.66PNN‐0.34PT. Interestingly, crystal structure of poled 0.66PNN‐0.34PT ceramic is determined to be single monoclinic phase. Furthermore, both its lattice parameters and volume variation present butterfly shape under electric field. It is demonstrated that macroscopic strain of 0.66PNN‐0.34PT stems mainly from intrinsic structure. The present study provides evidence for the relationship between microstructure and macroscopic properties, which is beneficial to the design of new materials with piezoelectric properties.

中文翻译：

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Pb（Ni1 / 3Nb2 / 3）O3-PbTiO3的原位同步加速器衍射结构与压电性能的系统研究

铅基铁电材料由于其出色的铁电和压电性能而广泛用于工业应用和日常生活中。Pb（Ni _1/3 Nb _2/3）O ₃ -PbTiO ₃（PNN-PT）是典型的二元弛豫铁电体系，其精细结构和压电性能尚未得到系统的研究。在这项研究中，基于电场的晶体结构和铁电，压电的变化，以及与组合物和温度的介电性能的演进（1 -  X）PNN- X PT（0.32≤  X ≤0.36）对陶瓷进行了详细的研究。在0.66PNN-0.34PT时可获得最佳性能，最大压电系数为d ₃₃560 pC / N和28 684的大介电常数。原位高能同步加速器衍射用于确定0.66PNN-0.34PT性能增强的结构起源。有趣的是，极化的0.66PNN-0.34PT陶瓷的晶体结构被确定为单斜晶相。此外，在电场作用下，其晶格参数和体积变化均呈现蝶形。结果表明，0.66PNN-0.34PT的宏观应变主要来源于固有结构。本研究为微观结构和宏观性能之间的关系提供了证据，这有利于设计具有压电性能的新材料。