Li Junzi, Jing Qiang, Xiao Shuyu, Gao Yang, Wang Yue, Zhang Wenjing, Sun Xiao Wei, Wang Kai, He Tingchao
College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, P. R. China.
Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R China.
J Phys Chem Lett. 2020 Jun 18;11(12):4817-4825. doi: 10.1021/acs.jpclett.0c00967. Epub 2020 Jun 8.
All-inorganic perovskite (CsPbX, X = Cl, Br, I) nanorods (NRs) not only retain their inherent advantages such as a high photoluminescence quantum yield and broad wavelength tunability but also exhibit superior photophysical properties including their extremely strong multiphoton absorption (MPA). However, the spectral dynamics and MPA properties of CsPbX NRs have not been fully investigated. Here, we report comprehensive comparison studies on the femtosecond spectral dynamical properties of CsPb(BrCl), CsPbBr, and CsPb(BrI) NRs, including their influences on their hot-carrier cooling, biexciton lifetime, and biexciton binding energy. Interestingly, although the three kinds of perovskite NRs have similar diameters and lengths, they differ significantly in their nonlinear optical properties, among which the CsPb(BrI) displayed the greatest MPA cross sections. Furthermore, the multiphoton-excited stimulated emission of CsPb(BrCl) and CsPbBr NRs is demonstrated. This work indicates that CsPbX (X = Cl, Br, I) NRs are excellent candidates for exploring their applications in different optoelectronic devices.
全无机钙钛矿（CsPbX，X = Cl、Br、I）纳米棒（NRs）不仅保留了其固有优势，如高光致发光量子产率和宽波长可调性，还展现出卓越的光物理性质，包括极强的多光子吸收（MPA）。然而，CsPbX纳米棒的光谱动力学和MPA性质尚未得到充分研究。在此，我们报告了关于CsPb(BrCl)、CsPbBr和CsPb(BrI)纳米棒飞秒光谱动力学性质的综合比较研究，包括它们对热载流子冷却、双激子寿命和双激子结合能的影响。有趣的是，尽管这三种钙钛矿纳米棒具有相似的直径和长度，但它们的非线性光学性质却有显著差异，其中CsPb(BrI)表现出最大的MPA截面。此外，还展示了CsPb(BrCl)和CsPbBr纳米棒的多光子激发受激发射。这项工作表明，CsPbX（X = Cl、Br、I）纳米棒是探索其在不同光电器件中应用的极佳候选材料。
