Faculty of Chemistry and Chemical Engineering, Engineering Research Center for Titanium Based Functional Materials and Devices in Universities of Shaanxi Province, Key Laboratory of Functional Materials of Baoji, Baoji University of Arts and Sciences, 1 Hi-Tech Avenue, Baoji, Shaanxi 721013, China.
College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
Inorg Chem. 2023 Jul 3;62(26):10408-10419. doi: 10.1021/acs.inorgchem.3c01286. Epub 2023 Jun 22.
KNbO (KN) with a perovskite structure is an outstanding representative of lead-free piezoelectric materials, and its mesocrystals have broad application prospects in the fields of catalysis, energy storage, and conversion. However, the formation conditions of KN mesocrystals reported so far are difficult owing to their high aspect ratio and excellent preferred orientation. In this study, the solvothermal process was used successfully to prepare the flake-like potassium salt of Lindquist hexaniobate (KNbO·10HO). Subsequently, the precursor niobate was calcined to prepare two-dimensional (2D) plate-like KN mesocrystals. The formation mechanism of the plate-like KN mesocrystals is further revealed from a paired topochemical mesocrystal conversion of KNbO·10HO niobate. Finally, the microscopic piezoelectric and photocatalytic responses of the obtained plate-like KN mesocrystals were investigated. The high piezoelectric coefficient of plate-like KN mesocrystals implies that excellent charge separation promotes the photocatalytic performance of rhodamine B (RhB). This study provides a strategy for the efficient application of 2D oriented materials in the field of piezoelectricity and photocatalysis.
具有钙钛矿结构的 KNbO（KN）是无铅压电材料的杰出代表，其准晶在催化、储能和转化等领域具有广阔的应用前景。然而，由于其高纵横比和优异的择优取向，迄今为止报道的 KN 准晶的形成条件较为苛刻。本研究采用溶剂热法成功制备了 Lindquist 六铌酸盐（KNbO·10H2O）的片状钾盐。随后，将前驱体铌酸盐煅烧得到二维（2D）板状 KN 准晶。通过 KNbO·10H2O 铌酸盐的配对拓扑准晶转化，进一步揭示了板状 KN 准晶的形成机制。最后，研究了所得板状 KN 准晶的微观压电和光催化响应。板状 KN 准晶的高压电系数表明，优异的电荷分离促进了罗丹明 B（RhB）的光催化性能。本研究为二维定向材料在压电和光催化领域的高效应用提供了一种策略。
