17082-69-8Relevant academic research and scientific papers
Tailoring photoluminescence properties in ionic nanoparticle networks
Kronstein, Martin,Akbarzadeh, Johanna,Drechsel, Christina,Peterlik, Herwig,Neouze, Marie-Alexandra
, p. 10763 - 10774 (2014/12/10)
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. Inducing luminescence: Interesting luminescence properties were observed in ionic nanoparticle networks containing no luminophore. "Playing" with the nanoparticle linker allowed tailoring of the excitation and emission wavelength over a broad range. A clear trend between the obtained structural parameters (obtained from small-angle X-ray scattering experiments) and the luminescence quantum yields of the ionic nanoparticle network materials could be evidenced (see figure).
