Great Disparity in Photoluminesence Quantum Yields of Colloidal CsPbBr 3 Nanocrystals with Varied Shape: The Effect of Crystal Lattice Strain

作者：Jiangtao Zhao, Mei Liu, Fang Li, Shenlong Jiang, Jingtian Zhou, Huaiyi Ding, Hongwen Huang, Wen Wen, Zhenlin Luo, Qun Zhang, Xiaoping Wang, Chen Gao · 发表于：The Journal of Physical Chemistry Letters · 年份：2017 · DOI：10.1021/acs.jpclett.7b01083 · 被引用次数：38 · 研究领域：Perovskite Materials and Applications、Luminescence Properties of Advanced Materials、Quantum Dots Synthesis And Properties

Understanding the big discrepancy in the photoluminesence quantum yields (PLQYs) of nanoscale colloidal materials with varied morphologies is of great significance to its property optimization and functional application. Using different shaped CsPbBr 3 nanocrystals with the same fabrication processes as model, quantitative synchrotron radiation X-ray diffraction analysis reveals the increasing trend in lattice strain values of the nanocrystals: nanocube, nanoplate, nanowire. Furthermore, transient spectroscopic measurements reveal the same trend in the defect quantities of these nanocrystals. These experimental results unambiguously point out that large lattice strain existing in CsPbBr 3 nanoparticles induces more crystal defects and thus decreases the PLQY, implying that lattice strain is a key factor other than the surface defect to dominate the PLQY of colloidal photoluminesence materials.