Résumé
The sol−gel preparation of a bridged silsesquioxane containingeuropium(III) salts and 2-thenoyltrifluoroacetone has been achieved from a newethane tetracarboxamide-based organosilane. Free-standing films with thicknessesup to 440 μm and maximum absolute quantum yield (q) of 0.34 ± 0.03(excitation at 320 nm) were prepared by the drop cast method, while thin films(∼200−400 nm) spin-coated on glass substrates led to highly luminescentcoatings with q = 0.60 ± 0.02 (excitation at 345 nm). The thin films were testedas planar luminescent solar concentrators and the optimized device displays anoptical conversion efficiency of 12.3% in the absorbing spectral region of theactive layer (300−380 nm).