Ruan Longfei, Shen Wei, Wang Aifei, Xiang Aishuang, Deng Zhengtao
Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing National Laboratory of Microstructures, Collaborative Innovation Center of Chemistry for Life Sciences, Nanjing University , Nanjing, Jiangsu 210093, People's Republic of China.
J Phys Chem Lett. 2017 Aug 17;8(16):3853-3860. doi: 10.1021/acs.jpclett.7b01657. Epub 2017 Aug 4.
Controlled synthesis of colloidal all-inorganic lead halide perovskite semiconductor nanocrystals, such as CsPbBr, with tunable size, shape, composition, and crystalline phase have recently attracted wide interest for photonic and optoelectronic applications. Herein, we report a new strategy for using alkyl-thiols to induce the transformation of CsPbBr to perovskite-related cesium lead halide (CsPbBr) with controlled morphology and a crystalline phase at room temperature. By rational tuning the ratios of the alkyl-thiol ligands to alkyl-amines or to alkyl-acids, the as-synthesized colloidal nanocrystals can be rationally controlled from orthorhombic crystalline-phase CsPbBr to tetragonal-phase CsPbBr nanosheets and nanowires with high yield. Significantly, the tetragonal CsPbBr nanowires and nanosheets have high stability in high-temperature and high-humidity environments. These findings may open new directions for large-scale synthesis of shape- and crystalline phase-controlled perovskite nanocrystals for high-performance, low-cost optical electronic and optoelectronic devices.
胶体全无机铅卤化物钙钛矿半导体纳米晶体（如CsPbBr）的可控合成，其尺寸、形状、组成和晶相可调，最近在光子和光电子应用中引起了广泛关注。在此，我们报道了一种新策略，即在室温下使用烷基硫醇诱导CsPbBr转变为具有可控形态和晶相的钙钛矿相关铯铅卤化物（CsPbBr）。通过合理调节烷基硫醇配体与烷基胺或烷基酸的比例，可以将合成的胶体纳米晶体从正交晶相CsPbBr合理控制为四方相CsPbBr纳米片和纳米线，产率很高。值得注意的是，四方相CsPbBr纳米线和纳米片在高温高湿环境中具有高稳定性。这些发现可能为大规模合成形状和晶相可控的钙钛矿纳米晶体开辟新方向，用于高性能、低成本的光电器件和光电子器件。
