title: Light Triggered Co-Assembly of Photocleavable Copolymers and Polyoxometalates with Enhanced Photoluminescence.
abstract: A novel co-assembly based on the block copolymer bearing photocleavable groups and macroanionic polyoxometalates Na9[Ln(W5O18)2] (LnW10, Ln = Eu, Dy) triggered by UV light is realized in aqueous solution. The copolymer synthesized by atom transfer radical polymerization (ATRP) undergoes irreversible cleavage upon UV irradiation to generate primary amine (pKa ≈ 8-9) residues which are completely protonated under a neutral pH in aqueous solution. Electrostatic attractions between the resulting positively charged copolymers and anionic LnW10drive the formation of assemblies. In situ small angle X-ray scattering and transmission electron microscopy are used to characterize the morphology of the assemblies. The microenvironments around polyoxometalates in the core of hybrid assemblies become highly hydrophobic, resulting in dramatically enhanced photoluminescence with the obvious intensity enhancement. The solution parameters pH and salt additives show great effects on the formation of assemblies.
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China.|Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Shi
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Guan
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Qiao
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Wan
mesh_terms: D049449:Luminescence; D015394:Molecular Structure; D055668:Photochemical Processes; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D011108:Polymers
keywords: block copolymers; photocleavages; polyoxometalates; self-assembly