Reversible photochromic and photoluminescence in iodide perovskites

Wayesh Qarony, Mohammad Kamal Hossain, Mohammad Ismail Hossain, Longhui Zeng, Sainan Ma, Kin Man Yu, Alberto Salleo, Dietmar Knipp, Cho Tung Yip, Yuen Hong Tsang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)


Color imaging experiment demonstrates a photochromic behavior of mixed-halide perovskites upon dark and light excitation, while the color emitted by the crystals changes from red to yellow and vice versa with the intensity of excitation light source. Unlike the photochromic property commonly observed in solution-state polymer materials, solid-state perovskite materials with photochromic behavior might open wide applications in consumer products and electronic devices. In the next part, we report on a reversible photoluminescence (PL) peak in iodide-based organic-inorganic lead halide perovskite materials under a 2-photon absorption process, while tuning the excitation wavelength. Intriguingly, two shorter wavelength peaks are visible and become prominent when the excitation photon energy is being tuned in the high energy spectrum, while laser power is remained constant. The same phenomenon of reversible PL peak is also observed in various iodine-based organic-inorganic halides as well as all-inorganic perovskite single crystals and polycrystals. We attribute to the reversible PL peak phenomenon to the photoinduced structural deformation and the associated change in the optical bandgap of iodide perovskites under the femtosecond laser excitation. Our findings will introduce a degree of freedom in future research as well as adding functionalities to optoelectronic applications in these emerging perovskite materials-based devices.

Original languageEnglish
Article number138950
JournalThin Solid Films
Publication statusPublished - 1 Nov 2021


  • 2-Photon absorption
  • Femtosecond laser
  • Perovskites
  • Photochromic
  • Reversible photoluminescence peak

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Materials Chemistry


Dive into the research topics of 'Reversible photochromic and photoluminescence in iodide perovskites'. Together they form a unique fingerprint.

Cite this