Increasing the Phase Stability of CsPbI3 Nanocrystals by Zn2+ and Cd2+ Addition: Synergy of Transmission Electron Microscopy and Molecular Dynamics

被引：0

作者：

Skvortsova, Irina ^{[1
,2
]}

Braeckevelt, Tom ^{[3
,4
]}

De Backer, Annick ^{[1
,2
]}

Schrenker, Nadine ^{[1
,2
]}

Pradhan, Bapi ^{[4
]}

Hofkens, Johan ^{[4
]}

Van Aert, Sandra ^{[1
,2
]}

Van Speybroeck, Veronique ^{[3
]}

Bals, Sara ^{[1
,2
]}

机构：

[1] Univ Antwerp, Electron Microscopy Mat Sci EMAT, B-2020 Antwerp, Belgium

[2] Univ Antwerp, NANOlab Ctr Excellence, B-2020 Antwerp, Belgium

[3] Univ Ghent, Ctr Mol Modeling CMM, B-9052 Zwijnaarde, Belgium

[4] Katholieke Univ Leuven, Dept Chem, B-3001 Leuven, Belgium

来源：

ACS NANO | 2025年

基金：

比利时弗兰德研究基金会;

关键词：

perovskites; doping; Ruddlesden-Popperphase defects; phase stability; transmission electronmicroscopy; molecular dynamics; EFFECTIVE IONIC-RADII; HALIDE PEROVSKITES; MODEL;

D O I：

10.1021/acsnano.5c01825

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Metal halide perovskites (MHPs) are emerging as promising materials for optoelectronic and photovoltaic applications due to their favorable electronic properties, including a tunable bandgap. However, achieving high stability for these materials remains a critical challenge, particularly for CsPbI3, whose photoactive phases spontaneously convert into a nonphotoactive yellow orthorhombic delta-phase under ambient conditions. This transformation results in a significant increase in bandgap and a loss of photoactive functionality. In this study, we investigate the impact of Zn2+ and Cd2+ dopants on the phase stability of CsPbI3 nanocrystals (NCs), emphasizing the formation of Ruddlesden-Popper (RP) planar defects, which are frequently observed during compositional tuning. Using transmission electron microscopy (TEM), we follow the temporal evolution of the phase transformation, where black-phase NCs agglomerate and form elongated microtubes with a yellow-phase crystal structure. Our observations demonstrate that doped samples are significantly more stable, while the dopants are key factors in the formation of the RP-like defects with specific atomic arrangements. Using a combination of quantitative TEM and molecular dynamics (MD) simulations we characterize the structure and composition of as-found RP-like defects and elucidate their role in stabilizing the photoactive phases of CsPbI3 through decreased phase transition kinetics.

引用

页数：11