Photostability and Photodegradation Processes in Colloidal CsPbI3 Perovskite Quantum Dots

Research output: Contribution to journalArticle

Abstract

All-inorganic CsPbI3 perovskite quantum dots (QDs) have attracted intense attention for their successful application in photovoltaics (PVs) and optoelectronics that are enabled by their superior absorption capability and great photoluminescence (PL) properties. However, their photostability remains a practical bottleneck and further optimization is highly desirable. Here, we studied the photostability of as-obtained colloidal CsPbI3 QDs suspended in hexane. We found that light illumination does induce photodegradation of CsPbI3 QDs. Steady-state spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and transient absorption spectroscopy verified that light illumination leads to detachment of the capping agent, collapse of the CsPbI3 QD surface, and finally aggregation of surface Pb0. Both dangling bonds containing surface and Pb0 serve as trap states causing PL quenching with a dramatic decrease of PL quantum yield. Our work provides a detailed insight about the correlation between the structural and photophysical consequences of the photodegradation process in CsPbI3 QDs and may lead to the optimization of such QDs toward device applications.

Details

Authors
Organisations
External organisations
  • Southwest University
  • Technical University of Denmark
  • Ivan Franko National University of Lviv
  • ELI Attosecond Light Pulse Source (ELI-ALPS)
  • German Electron Synchrotron (DESY)
  • Lund University
  • University of Bologna
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Materials Chemistry
  • Physical Chemistry

Keywords

  • blue-shift emission, light illumination, photodegradation mechanism, surface collapse, trap states
Original languageEnglish
Pages (from-to)39222-39227
Number of pages6
JournalACS Applied Materials and Interfaces
Volume10
Issue number45
Publication statusPublished - 2018 Nov 14
Publication categoryResearch
Peer-reviewedYes