Insight into the Structures and Photophysics of Zn-Alloyed Lead Bromide Perovskite Nanocrystals Synthesized by a Post-Ion-Exchange Method and a One-Pot Hot Injection Method

作者：Xing Ji, Rong Lü, Anchi Yu · 发表于：The Journal of Physical Chemistry C · 年份：2024 · DOI：10.1021/acs.jpcc.4c00184 · 被引用次数：9 · 研究领域：Perovskite Materials and Applications、2D Materials and Applications、Optical properties and cooling technologies in crystalline materials

Doping Zn 2+ into the CsPbX 3 nanocrystal is a straightforward and feasible operation, but there is still no systematic study of its structures and photophysics. Herein, we respectively fabricated two kinds of Zn-alloyed CsPbBr 3 nanocrystals through a post-ion-exchange (CsPbBr 3 -ZnBr 2 -PIEX) and one-pot hot injection (CsPbBr 3 -ZnBr 2 -OPHI) method and conducted comprehensive investigations on them. It is found that the photoluminescence intensities of both CsPbBr 3 -ZnBr 2 -PIEX and CsPbBr 3 -ZnBr 2 -OPHI nanocrystals are significantly enhanced as compared to that of the pristine CsPbBr 3 nanocrystal. The steady-state absorption and photoluminescence, XRD, SEM–EDX, ICP–OES, XPS, and TEM studies demonstrate that Zn 2+ can be incorporated into the [PbBr 6 ] 4– framework of the CsPbBr 3 -ZnBr 2 -OPHI nanocrystal and cause its lattice contraction, while the structure of the CsPbBr 3 -ZnBr 2 -PIEX nanocrystal remains unchanged as that of a pristine CsPbBr 3 nanocrystal. The femtosecond transient absorption spectroscopy studies confirm that Zn 2+ incorporation into the [PbBr 6 ] 4– framework of the CsPbBr 3 -ZnBr 2 -OPHI nanocrystal has a dramatic effect on its hot carrier cooling time, biexciton Auger recombination time, and biexciton binding energy.