title: First Orange Fluorescence Composite Film Based on Sm-Substituted Tungstophosphate and Its Electrofluorochromic Performance.
abstract: We chose a Sm-containing sandwich-type tungstophosphate K3Cs8[Sm(PW11O39)2]·10H2O (SmPW11) as a molecular dyad, which contains photoluminescence and electrochromism components in a skeletal structure, and investigated its electrofluorochromic performance both in solution and in composite films. First, the electrochemical activity and luminescence property of SmPW11 were studied in different pH solutions to determine the optimal pH solution medium; and then, the electrofluorochromic performance of SmPW11 was investigated under the optimized pH solution medium. Subsequently, the composite films containing SmPW11 were prepared on quartz substrates and conductive ITO substrates through a layer-by-layer (LbL) assembly method, using PDDA and PEI as molecular linkers. Characterization methods of the composite films include UV-vis spectra, fluorescence spectroscopy, cyclic voltammetry (CV), bulk electrolysis with coulometry, chronoamperometry, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Finally, in situ UV-vis and fluorescence spectroelectrochemical systems were used to research electrofluorochromic properties for the composite films under electrochemical modulation. The results indicate that the composite films display not only orange luminescence emission but also reversible orange luminescence switching behaviors manipulated by the redox process of tungstophosphate species PW11 via the energy transfer between the orange luminescence component Sm and electroreduced species of tungstophosphate PW11.
authors.affiliation: College of Chemistry, State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun, 130012, People's Republic of China.
authors.forename: Wenmei
authors.initials: W
authors.lastname: Gao
authors.affiliation: College of Electrical and Electronic Engineering, Changchun University of Technology , Changchun, 130012, People's Republic of China.
authors.forename: Tian
authors.initials: T
authors.lastname: Yu
authors.affiliation: College of Chemistry, State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun, 130012, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Du
authors.affiliation: College of Chemistry, State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun, 130012, People's Republic of China.
authors.forename: Ruiqiang
authors.initials: R
authors.lastname: Wang
authors.affiliation: College of Chemistry, State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun, 130012, People's Republic of China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Wu
authors.affiliation: College of Chemistry, State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun, 130012, People's Republic of China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Bi
keywords: composite film; layer-by-layer assembly; luminescence switching; orange luminescence; samarium; tungstophosphate