Wang Yuying, Zheng Deyi, Mao Runyu, Wang Xu
College of Materials and Metallurgy, Gui Zhou University, Guiyang, China.
Front Chem. 2022 Dec 13;10:1089739. doi: 10.3389/fchem.2022.1089739. eCollection 2022.
Bismuth Layer Structured Ferroelectrics (BLSFs) have always been an important research direction of high Curie temperature piezoelectrical ceramics, and the construction of intergrowth structure has been considered as an effective method to improve the electric properties of BLSFs. There are many literatures about intergrowth structure improving electrical performance, but few reports analyze the influence of the construction of intergrowth structure on the internal defects and electrical properties in BLSFs. In this study, (1-) BaBiTiO - BiTiO ceramic samples with intergrowth bismuth layer structure were fabricated by a conventional solid-state reaction method, and the mechanism of the influence of intergrowth structure construction on the structure and electrical properties of BLSFs has been discussed. The crystal structure, phase composition, microstructure, dielectric and piezoelectric performance, relaxation behavior and AC conductivity of ceramic samples were systematically investigated. It has been found that the construction of intergrowth structure can significantly inhibit the generation of oxygen vacancies. The concentration of the oxygen vacancies plays an important role, and its reduction will lead to the inhibition of grain growth and the increase of the relaxation activation energy of ceramics. In addition, the intergrowth structure construction also affects the symmetry of ceramics in the -axis direction, thus affecting the electrical properties of ceramics.
铋层状结构铁电体(BLSFs)一直是高居里温度压电陶瓷的重要研究方向,构建共生结构被认为是改善BLSFs电学性能的有效方法。关于共生结构改善电学性能的文献众多,但很少有报道分析共生结构的构建对BLSFs内部缺陷和电学性能的影响。在本研究中,采用传统固相反应法制备了具有共生铋层结构的(1-)BaBiTiO - BiTiO陶瓷样品,并探讨了共生结构构建对BLSFs结构和电学性能的影响机制。系统研究了陶瓷样品的晶体结构、相组成、微观结构、介电和压电性能、弛豫行为及交流电导率。研究发现,共生结构的构建能显著抑制氧空位的产生。氧空位浓度起着重要作用,其减少会导致晶粒生长受到抑制以及陶瓷弛豫激活能增加。此外,共生结构的构建还会影响陶瓷在轴方向的对称性,从而影响陶瓷的电学性能。