Construction and Photoluminescence of Monophase Hybrid Materials Derived from a Urea‐Based Bis‐Silylated Bipyridine

Abstract

AbstractA urea‐based bis‐silylated bipyridine ligand derived from 4,4′‐diamino‐2,2′‐bipyridine has been prepared. Organic–inorganic hybrid materials with a high loading of lanthanide 2,2‐bipyridine moieties were obtained by using the silylated bipyridine as the only siloxane network precursor in the presence of lanthanide ions (or lanthanide complexes). The in‐situ formation of lanthanide complexes from lanthanide ions and the silylated bipyridine during the sol–gel processing was confirmed by the luminescence behavior of the obtained hybrid materials and that of the corresponding pure lanthanide complex [Ln(bpy)2Cl3·2H2O]. Tris(2‐thenoyltrifluoroacetonato)europium(III) dihydrate complexes were coupled to the hybrid materials via adduct formation with the nitrogen atoms from bis‐silylated bipyridine, and the coordinated water molecules were expelled from the first coordination sphere of the lanthanide(III) ion as revealed by the much longer lifetime of the hybrid material compared with that of the pure tris(2‐thenoyltrifluoroacetonato)europium(III). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)