Abstract Ferroelectric mesocrystalline nanocomposite is a promising nanomaterial for enlarged piezoelectric response and dielectric response obtained using lattice strain engineering. In this study, mesocrystalline BaTiO3/Bi0.5K0.5TiO3 (BT/BKT) nanocomposites were prepared via a two-step topochemical process. In the first step, a platelike layered titanate H1.07Ti1.73O4·nH2O (abbreviated as HTO) precursor was solvothermally treated in a Ba(OH)2 solution to synthesize a BaTiO3/HTO (abbreviated as BT/HTO) nanocomposite. In the second step, a BT/HTO-Bi2O3–K2CO3 mixture was heat-treated to obtain BT/BKT nanocomposite. The reactions occurring in the formation of BT/BKT nanocomposite are topochemical reactions. Nanostructural analysis shows that the BT/BKT nanocomposite is constructed from well-aligned [110]-oriented BT nanocrystals and [001]-oriented BKT nanocrystals. In the nanocomposite BT(001)/BKT(100), heteroepitaxial interface is formed, introducing a lattice strain at the interface owing to their lattice mismatch. The BT/BKT nanocomposite exhibits much larger d33* and er values than those of individual BT and BKT mesocrystals. The enlarged piezoelectric and dielectric responses show the potential application of lattice strain engineering to mesocrystalline nanocomposites for high-performance lead-free piezoelectric materials.

中文翻译：

---

铁电中晶 BaTiO3/Bi0.5K0.5TiO3 纳米复合材料：拓扑化学合成，增强压电和介电响应

摘要 铁电介晶纳米复合材料是一种很有前途的纳米材料，可用于扩大压电响应和使用晶格应变工程获得的介电响应。在这项研究中，中晶 BaTiO3/Bi0.5K0.5TiO3 (BT/BKT) 纳米复合材料是通过两步拓扑化学过程制备的。第一步，将片状层状钛酸盐H1.07Ti1.73O4·nH2O（简称HTO）前驱体在Ba(OH)2溶液中进行溶剂热处理，合成BaTiO3/HTO（简称BT/HTO）纳米复合材料。第二步，对BT/HTO-Bi2O3-K2CO3混合物进行热处理以获得BT/BKT纳米复合材料。在 BT/BKT 纳米复合材料的形成过程中发生的反应是拓扑化学反应。纳米结构分析表明，BT/BKT 纳米复合材料由排列良好的 [110] 取向的 BT 纳米晶体和 [001] 取向的 BKT 纳米晶体构成。在纳米复合材料 BT(001)/BKT(100) 中，形成异质外延界面，由于它们的晶格失配而在界面处引入晶格应变。BT/BKT 纳米复合材料表现出比单个 BT 和 BKT 介晶大得多的 d33* 和 er 值。放大的压电和介电响应显示了晶格应变工程在用于高性能无铅压电材料的中晶纳米复合材料中的潜在应用。BT/BKT 纳米复合材料表现出比单个 BT 和 BKT 介晶大得多的 d33* 和 er 值。放大的压电和介电响应显示了晶格应变工程在用于高性能无铅压电材料的中晶纳米复合材料中的潜在应用。BT/BKT 纳米复合材料表现出比单个 BT 和 BKT 介晶大得多的 d33* 和 er 值。放大的压电和介电响应显示了晶格应变工程在用于高性能无铅压电材料的中晶纳米复合材料中的潜在应用。