Tönu Pullerits
Professor
Photostability and Photodegradation Processes in Colloidal CsPbI3 Perovskite Quantum Dots
Author
Summary, in English
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.
Department/s
- Chemical Physics
- NanoLund: Centre for Nanoscience
- Centre for Analysis and Synthesis
Publishing year
2018-11-14
Language
English
Pages
39222-39227
Publication/Series
ACS Applied Materials and Interfaces
Volume
10
Issue
45
Document type
Journal article
Publisher
The American Chemical Society (ACS)
Topic
- Materials Chemistry
- Physical Chemistry (including Surface- and Colloid Chemistry)
- Condensed Matter Physics (including Material Physics, Nano Physics)
Keywords
- blue-shift emission
- light illumination
- photodegradation mechanism
- surface collapse
- trap states
Status
Published
ISBN/ISSN/Other
- ISSN: 1944-8244