Healing Perovskites at Room Temperature

  • Author: ChemistryViews.org
  • Published: 07 July 2016
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
  • Source / Publisher: Advanced Functional Materials/Wiley-VCH
thumbnail image: Healing Perovskites at Room Temperature

All-inorganic halide perovskite nanocrystals (IPNCs), for example, CsPbX3 (X = Cl, Br, I), have potential as materials for optoelectronic devices. IPNCs are stable, exhibit luminescence that is tunable over the whole visible spectrum, and show high quantum yields. The materials can be used as thin films, however, solution-processed films often have cracks and holes that hinder the efficient transport of charge carriers.

Haibo Zeng, Nanjing University of Science and Technology, China, and colleagues have developed a dissolution-recyrstallization process which can "heal" such cracks in perovskites at room temperature. The team first prepared CsPbBr3-nanocrystals by adding micrometer-sized CsPbBr3 particles to a mixture of toluene and the surfactants oleic acid and oleylamine. The mixture was then stirred for ten hours until a solubility equilibrium was reached. Thin films were prepared by soaking a substrate such as glass in a dispersion of the nanocrystals in toluene and centrifuging the substrate for 3 minutes.

To heal the defects in the prepared films, the film was covered with a filter paper and a mixture of toluene and ethanol was dropped on the filter and left to evaporate. This process was repeated multiple times. The solvent mixture dissolves sharp edges of the perovskite film, filles holes and cracks, and allows the perovskite to recrystallize upon evaporation. Toluene enhances the diffusion of the surfactant, while the more polar ethanol promotes the solvation of surface atoms.

The team built photodetectors (PDs) based on the treated perovskite films. The devices showed high external quantum efficiencies, fast response speeds, and high stability, and overall performed better than most otherplanar perovskite PDs. According to the researchers, the film modification method is suitable for all kinds of inorganic halide perovskite devices, especially for solution-processed flexible devices.


Article Views: 1976

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

Bookmark and Share

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission. more


ChemistryViews.org on Facebook

ChemistryViews.org on Twitter ChemistryViews.org on YouTube ChemistryViews.org on LinkedIn Sign up for our free newsletter

A product of ChemPubSoc Europe (16 European Chemical Societies)and Wiley-VCH