Facile purification of CsPbX3 (X = Cl-, Br-, I-) perovskite nanocrystals

Chujie Wang; Anthony S R Chesman; Wenping Yin; Laszlo Frazer; Alison M Funston; Jacek J Jasieniak

doi:10.1063/1.5123306

Facile purification of CsPbX₃ (X = Cl^-, Br^-, I^-) perovskite nanocrystals

J Chem Phys. 2019 Sep 28;151(12):121105. doi: 10.1063/1.5123306.

Authors

Chujie Wang¹, Anthony S R Chesman², Wenping Yin¹, Laszlo Frazer³, Alison M Funston³, Jacek J Jasieniak¹

Affiliations

¹ ARC Centre of Excellence in Exciton Science, Department of Materials Science and Engineering, Faculty of Engineering, Monash University, Clayton, VIC 3800, Australia.
² CSIRO Manufacturing, Ian Wark Laboratories, Bayview Ave., Clayton, VIC 3168, Australia.
³ ARC Centre of Excellence in Exciton Science, School of Chemistry, Monash University, Clayton, VIC 3800, Australia.

PMID: 31575186
DOI: 10.1063/1.5123306

Abstract

CsPbI₃ perovskite nanocrystals are a promising optoelectronic material when stabilized in their cubic phase. While ongoing efforts have addressed this structural challenge through a variety of meta-stabilization approaches, the postsynthesis purification of these nanocrystal dispersions has remained a challenge. In this article, we undertake a detailed investigation into the chemical, optical, and structural changes that arise during purification of CsPbI₃ nanocrystals. It is found that nanocrystal degradation can only be avoided through the judicious control of additives within each purification cycle. Under optimized additive-to-nanocrystal ratios, multiple purification cycles can be readily achieved, while retaining the quality and phase stability of the CsPbI₃. This facile purification protocol ensures the preparation of high purity and high quality CsPbI₃ nanocrystal inks that are suitable for better characterization or integration in optoelectronic devices. The approach has been generalized for CsPbX₃ (X = Cl^-, Br^-, and I^-).