@article{feddc3f26ca84c50bde158231343d9e1,
title = "Reversible photochromic and photoluminescence in iodide perovskites",
abstract = "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.",
keywords = "2-Photon absorption, Femtosecond laser, Perovskites, Photochromic, Reversible photoluminescence peak",
author = "Wayesh Qarony and Hossain, {Mohammad Kamal} and Hossain, {Mohammad Ismail} and Longhui Zeng and Sainan Ma and Yu, {Kin Man} and Alberto Salleo and Dietmar Knipp and Yip, {Cho Tung} and Tsang, {Yuen Hong}",
note = "Funding Information: We acknowledge Prof. Hiroyuki Fujiwara from Gifu University for providing us with different halide perovskites shown in Fig. 1(b). This work was financially supported by the grant from Shenzhen Municipal Science and Technology projects ( Grant No. JCYJ20180306171818204 ), The Hong Kong Research Grants Council of Hong Kong ( GRF 152093/18E ), and The Hong Kong Polytechnic University (Project number: G-YBVG, 1-ZVGH ). MKH and KMY acknowledge the financial support by a CityU SGP Grant ( No. 9380076 ). The access to the Leica TCS SP8 MP system was provided by the University Research Facility in Life Sciences (ULS) of The Hong Kong Polytechnic University. Thanks to the technical persons in ULS for their technical support as well. MKH and MIH are equally contributed. We would also like to thank Dr. Huiyu Yuan for the preparation of schematic of perovskite atomic structures. Funding Information: We acknowledge Prof. Hiroyuki Fujiwara from Gifu University for providing us with different halide perovskites shown in Fig. 1(b). This work was financially supported by the grant from Shenzhen Municipal Science and Technology projects (Grant No. JCYJ20180306171818204), The Hong Kong Research Grants Council of Hong Kong (GRF 152093/18E), and The Hong Kong Polytechnic University (Project number: G-YBVG, 1-ZVGH). MKH and KMY acknowledge the financial support by a CityU SGP Grant (No. 9380076). The access to the Leica TCS SP8 MP system was provided by the University Research Facility in Life Sciences (ULS) of The Hong Kong Polytechnic University. Thanks to the technical persons in ULS for their technical support as well. MKH and MIH are equally contributed. We would also like to thank Dr. Huiyu Yuan for the preparation of schematic of perovskite atomic structures. Publisher Copyright: {\textcopyright} 2021",
year = "2021",
month = nov,
day = "1",
doi = "10.1016/j.tsf.2021.138950",
language = "English",
volume = "737",
journal = "Thin Solid Films",
issn = "0040-6090",
publisher = "Elsevier B.V.",
}