[Zurück]

M. Kronstein, M.-A. Néouze:
"Photoluminescence of Novel lonic Silica Nanoparticle Networks";
Poster: E-MRS Spring Meeting 2012, Strasbourg; 14.05.2012 - 18.05.2012; in: "E-MRS Spring Meeting 2012 - Program", (2012), S. P2-8.

New hybrid materials with interesting photoluminescence properties based on ionic silica nanoparticle networks (ISNN) have been developed. For the synthesis of those hybrid materials imidazolium modified silica nanoparticles and halogen functionalized linkers were connected by means of a nucleophilic substitution in a "click-chemistry-like" reaction. The molecules used as linkers consists of aromatic or condensed aromatic compounds containing two end-standing CH2X-groups (X = Br, Cl) to enable the nucleophilic substitution. The photoluminescence measurements performed on these ISNN hybrid materials showed emission bands over a broad window (up to 200 nm with varying excitation wavelength). Whereas silica nanoparticles, as well as the imidazole or halogenalkyl modified silica nanoparticles are non luminescent. If some of the pure linkers are photoluminescent, their emission maximum occurs at a different wavelength as for the corresponding hybrid material. Thus the photoluminescence can be attributed to the self organization of the hybrid materials. The existence of strong π-π stacking in the hybrid material was highlighted when observing emission wavelength shifts by changing the linker. Quantum yields up to 26% were measured, making ISNN extremely promising for photoluminescence applications. In addition to this the ISNN hybrid materials can be processed into monolithic gels or transparent films.

Projektleitung Marie-Alexandra Néouze:
Ionische Verknüpfung von Nanopartikeln