Ultrasonication-assisted synthesis of CsPbBr3 and Cs4PbBr6 perovskite nanocrystals and their reversible transformation

Longshi Rao; Xinrui Ding; Xuewei Du; Guanwei Liang; Yong Tang; Kairui Tang; Jin Z Zhang

doi:10.3762/bjnano.10.66

Ultrasonication-assisted synthesis of CsPbBr₃ and Cs₄PbBr₆ perovskite nanocrystals and their reversible transformation

Beilstein J Nanotechnol. 2019 Mar 6:10:666-676. doi: 10.3762/bjnano.10.66. eCollection 2019.

Authors

Longshi Rao^{1

2}, Xinrui Ding¹, Xuewei Du¹, Guanwei Liang¹, Yong Tang¹, Kairui Tang³, Jin Z Zhang²

Affiliations

¹ Engineering Research Centre of Green Manufacturing for Energy-Saving and New-Energy Technology, School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China.
² Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA.
³ Mechanical Engineering, Pennsylvania State University, Harrisburg, PA 17057, USA.

Abstract

We demonstrate an ultrasonication-assisted synthesis without polar solvent of CsPbBr₃ and Cs₄PbBr₆ perovskite nanocrystals (PNCs) and their reversible transformation. The as-prepared CsPbBr₃ PNCs and Cs₄PbBr₆ PNCs exhibit different optical properties that depend on their morphology, size, and structure. The photoluminescence (PL) emission and quantum yield (QY) of the CsPbBr₃ PNCs can be tuned by changing the ultrasound power, radiation time, and the height of the vibrating spear. The optimized CsPbBr₃ PNCs show a good stability and high PL QY of up to 85%. In addition, the phase transformation between CsPbBr₃ PNCs and Cs₄PbBr₆ PNCs can be obtained through varying the amount of oleylamine (OAm) and water. The mechanism of this transformation between the CsPbBr₃ PNCs and Cs₄PbBr₆ PNCs and their morphology change are studied, involving ions equilibrium, anisotropic growth kinetics, and CsBr-stripping process.

Keywords: Cs4PbBr6 PNCs; CsPbBr3 PNCs; polar-solvent-free; reversible transformation; ultrasonication.