Zhao Yizhou, Zhang Siyu, Lu Yue, Lan Shangui, Zhu Cheng, Xiao Jiawen, Zai Huachao, Sui Manling, Li Dehui, Zhou Huanping, Li Yujing, Chen Qi
Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P. R. China.
Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing, 100124, P. R. China.
Small. 2019 Feb;15(6):e1804152. doi: 10.1002/smll.201804152. Epub 2019 Jan 15.
The low-dimensional halide perovskites have received enormous attention due to their unique photovoltaic and optoelectronic performances. Periodic spacers are used to inhibit the growth of 3D perovskite and fabricate a 2D counterpart with layered structure, mostly based on organic/inorganic cations. Herein, by introducing organic anions (e.g., pentanedioic acid (PDA) and hexanedioic acid (HDA) simultaneously), leaf-shaped (Cs Pb Br ) (PDA-HDA) microplates with low-dimensional structure are synthesized. They also exhibit significant photoluminescence (PL) centered at 540 nm with a narrow emission peak. The synthesis of single crystals of Pb(PDA) and Pb(HDA) allows to further clarify the crystal structure of (Cs Pb Br ) (PDA-HDA) perovskite and its structural evolution mechanism. Moreover, the cooperative introduction of dicarboxylic acid pairs with appropriate lengths is thermodynamically favored for the low-dimensional perovskite crystallization. The temperature-dependent PL indicates a V-shaped Stokes shift with elevated temperature that could be associated with the localization of excitons in the inorganic layers between organic dicarboxylic acid molecules. This work demonstrates low-dimensional halide perovskite with anionic spacers, which also opens up a new approach to the growth of low-dimensional organic-inorganic hybrid perovskite crystals.
低维卤化物钙钛矿因其独特的光伏和光电性能而受到广泛关注。周期性间隔物被用于抑制三维钙钛矿的生长，并制备具有层状结构的二维对应物，主要基于有机/无机阳离子。在此，通过同时引入有机阴离子（如戊二酸（PDA）和己二酸（HDA）），合成了具有低维结构的叶状（CsPbBr）（PDA-HDA）微板。它们还表现出以540nm为中心、发射峰窄的显著光致发光（PL）。Pb（PDA）和Pb（HDA）单晶的合成有助于进一步阐明（CsPbBr）（PDA-HDA）钙钛矿的晶体结构及其结构演化机制。此外，引入具有适当长度的二羧酸对在热力学上有利于低维钙钛矿的结晶。温度依赖的PL表明，随着温度升高，斯托克斯位移呈V形，这可能与有机二羧酸分子之间无机层中激子的局域化有关。这项工作展示了带有阴离子间隔物的低维卤化物钙钛矿，这也为低维有机-无机杂化钙钛矿晶体的生长开辟了一条新途径。
