Photodegradation of Organometal Hybrid Perovskite Nanocrystals: Clarifying the Role of Oxygen by Single-Dot Photoluminescence

Lige Liu; Luogen Deng; Sheng Huang; Pei Zhang; Jan Linnros; Haizheng Zhong; Ilya Sychugov

doi:10.1021/acs.jpclett.9b00143

Photodegradation of Organometal Hybrid Perovskite Nanocrystals: Clarifying the Role of Oxygen by Single-Dot Photoluminescence

J Phys Chem Lett. 2019 Feb 21;10(4):864-869. doi: 10.1021/acs.jpclett.9b00143. Epub 2019 Feb 11.

Authors

Lige Liu^{1

2}, Luogen Deng¹, Sheng Huang³, Pei Zhang^{2

4}, Jan Linnros², Haizheng Zhong³, Ilya Sychugov²

Affiliations

¹ Nanophotonics and Ultrafine Optoelectronic System, Beijing Key Laboratory, School of Physics , Beijing Institute of Technology , 5 South Street of Zhongguancun , 100081 Beijing , China.
² Department of Applied Physics , KTH-Royal Institute of Technology , Electrum 229 , 16440 Kista , Sweden.
³ School of Materials Science & Engineering , Beijing Institute of Technology , 5 South Street of Zhongguancun , 100081 Beijing , China.
⁴ Henan Key Lab of Information-based Electrical Appliances, School of Electrical and Information Engineering , Zhengzhou University of Light Industry , 450002 Zhengzhou , China.

PMID: 30730749
DOI: 10.1021/acs.jpclett.9b00143

Abstract

Photostability has been a major issue for perovskite materials. Understanding the photodegradation mechanism and suppressing it are of central importance for applications. By investigating single-dot photoluminescence spectra and the lifetime of MAPbX₃ (MA = CH₃NH₃⁺, X = Br, I) nanocrystals with quantum confinement under different conditions, we identified two separate pathways in the photodegradation process. The first is the oxygen-assisted light-induced etching process (photochemistry). The second is the light-driven slow charge-trapping process (photophysics), taking place even in oxygen-free environment. We clarified the role of oxygen in the photodegradation process and show how the photoinduced etching can be successfully suppressed by OSTE polymer, preventing an oxygen-assisted reaction.