Liu Zhenyang, Yang Hanjun, Wang Junyu, Yuan Yucheng, Hills-Kimball Katie, Cai Tong, Wang Ping, Tang Aiwei, Chen Ou
Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, United States.
Key Laboratory of Luminescence and Optical Information Ministry of Education, School of Science, Beijing Jiaotong University, Beijing 100044, China.
Nano Lett. 2021 Feb 24;21(4):1620-1627. doi: 10.1021/acs.nanolett.0c04148. Epub 2021 Feb 11.
Morphology control represents an important strategy for the development of functional nanomaterials and has yet to be achieved in the case of promising lead-free double perovskite materials so far. In this work, high-quality CsAgBiX (X = Cl, Br, I) two-dimensional nanoplatelets were synthesized through a newly developed synthetic procedure. By analyzing the optical, morphological, and structural evolutions of the samples during synthesis, we elucidated that the growth mechanism of lead-free double perovskite nanoplatelets followed a lateral growth process from mono-octahedral-layer (half-unit-cell in thickness) cluster-based nanosheets to multilayer (three to four unit cells in thickness) nanoplatelets. Furthermore, we demonstrated that CsAgBiBr nanoplatelets possess a better performance in photocatalytic CO reduction compared with their nanocube counterpart. Our work demonstrates the first example with two-dimensional morphology of this important class of lead-free perovskite materials, shedding light on the synthetic manipulation and the application integration of such promising materials.
形态控制是功能纳米材料开发的一项重要策略，而迄今为止，在有前景的无铅双钙钛矿材料方面尚未实现。在这项工作中，通过新开发的合成方法合成了高质量的CsAgBiX（X = Cl、Br、I）二维纳米片。通过分析样品在合成过程中的光学、形态和结构演变，我们阐明了无铅双钙钛矿纳米片的生长机制遵循从基于单八面体层（厚度为半个晶胞）簇的纳米片到多层（厚度为三到四个晶胞）纳米片的横向生长过程。此外，我们证明了CsAgBiBr纳米片与其纳米立方体对应物相比，在光催化CO还原方面具有更好的性能。我们的工作展示了这类重要的无铅钙钛矿材料二维形态的首个实例，为这类有前景材料的合成操控和应用整合提供了启示。
