[Zurück]

M. Kronstein, K. Kriechbaum, J. Akbarzadeh, H. Peterlik, M.-A. Néouze:
"Thermochromism of copper Chloride imidazolium nanoparticle networks";
Vortrag: ILMAT 2013, Montpellier, France; 18.11.2013 - 20.11.2013; in: "ILMAT 2013 - Program and Abstracts", (2013), S. OP-50.

Hybrid nanoparticle assemblies, called lonic Nanoparticle Networks (INN), have been designed. The three dimensional networks were prepared by linking modified metal oxide nanoparticles by means of a click chemistry like reaction between complementary functional ligands. The click-chemistry like reaction consists in a nucleophilic Substitution, forming imidazolium halide linking units.
The INN material with chloride as counter ion allows the complexation of copper dichloride. This complexation reaction leads to the formation of copper tetrachloride complexes within the skeleton of the INN material. The obtained material is green and showed irreversible thermochromic behaviour with a clear colour change from green to yellow at 180°C. The structural change induced by temperature originates in a configuration change of the copper complex. This change was studied by DSC and in-situ SAXS (Small Angle X-ray Scattering) experiments with temperature program.
The INN material was compared to copper imidazolium complexes, without the presence of silica nanoparticles, and to the chloride containing INN material, which both are not thermochromic.
Additionally the INN materials in general have shown many interesting properties, e.g. photoluminescence properties and thermal stability. Furthermore the INN materials can be used as solid state catalysts for the cycloaddition.