title: Flexible self-supporting nanofibers thin films showing reversible photochromic fluorescence.
abstract: Highly sensitive stimuli-responsive fluorescent films play an important role in smart sensors and readable optical devices. However, systems involving light-driven fluorescence changes are still limited compared with photochromic materials that simply change color upon photostimulation. Herein, by incorporation of stilbene-based molecules into a poly(vinyl alcohol) host, we have developed new flexible self-supporting nanofiber films that exhibited fast and obvious photochromic fluorescence (PCF). The reversible transfer between two fluorescent states can be easily recycled. Fluorescence microscopy and atomic force microscopy images supplied in situ evidence of changes in fluorescence and surface morphology, respectively. Density functional theoretical calculations showed that the PCF can be attributed to photoisomerization of the stilbene-based molecules. Therefore, based on the combination of experimental and theoretical studies, this work not only supplies new stilbene-based systems with light-induced fluorescence change, but also gives detailed understanding on the photoisomerization and PCF processes of the nanofibers systems. We anticipate that these PCF films can be applied in erasable memory devices and antiforgery materials, and that our strategy may be extended to other systems to fabricate multistimuli-responsive fluorescent materials.
authors.affiliation: †State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Gao
authors.affiliation: †State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
authors.forename: Ding
authors.initials: D
authors.lastname: Cao
authors.affiliation: §College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Guan
authors.affiliation: †State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.|‡Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China.
authors.forename: Dongpeng
authors.initials: D
authors.lastname: Yan
keywords: cyanostilbene; nanofibers; photochromic fluorescence; photoismerization; self-supporting films