title: Tailoring photoluminescence properties in ionic nanoparticle networks.
abstract: To investigate the original and promising luminescence properties of ionic nanoparticle networks (INN), various material compositions were investigated. In this work, the linker used to network the silica nanoparticles was varied; numerous substituted or non-substituted imidazolium, pyrazolium and pyridinium linkers are presented. Photoluminescence experiments on the INN hybrid materials revealed strong emission bands over a broad range in the visible region of the light spectrum. Varying the aromatic linker between the imidazolium units induced clear shifts of the emission maxima up to 100 nm, as a consequence of π-π stacking interactions. Steric hindrance and inductive effects of the substituents, introduced on the aromatic units, also strongly influenced the luminescence properties of the materials by modifying the π-π stacking between the imidazolium rings. Small and wide-angle X-ray scattering (SAXS, WAXS) experiments revealed a clear trend between the obtained structural parameters (short-range order parameter and distance of the aromatic units within the hybrid material) and the luminescence quantum yields of the INN materials.
authors.affiliation: Institute of Materials Chemistry - Applied Inorganic Chemistry, Vienna University of Technology; 1060 Vienna (Austria).
authors.forename: Martin
authors.initials: M
authors.lastname: Kronstein
authors.forename: Johanna
authors.initials: J
authors.lastname: Akbarzadeh
authors.forename: Christina
authors.initials: C
authors.lastname: Drechsel
authors.forename: Herwig
authors.initials: H
authors.lastname: Peterlik
authors.forename: Marie-Alexandra
authors.initials: MA
authors.lastname: Neouze
keywords: SAXS; nanoparticles; networks; photoluminescence; silica