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Z. Naturforsch. 2014,
69b, 210 – 216
doi:10.5560/ZNB.2014-3278
Efficient Red Emission from Europium Chelate-Silicone Host-Guest Hybrids
1 Münster University of Applied Sciences, Department of Chemical Engineering, Stegerwaldstraße 39, 48565 Steinfurt, Germany
2 On leave from Volga State University of Technology, Department of Physics, Lenin-pl.3, Yoshkar-Ola, 424000, Russia
Reprint requests to Prof. Dr. U. Kynast. Fax: +49(0)2551-962119. E-mail:
uk@fh-muenster.de
Received October 2013 / published online February 17, 2014
Due to their ease of fabrication, chemical stability and optical transparency polydimethylsiloxane-derived silicones ([O-Si(CH3)2]∞) are excellent matrices to enable optical functions. We here report on the luminescence of silicone hybrids with red-emitting europium diketonate complexes, which have not been described previously in this matrix. The problem of too low solubility of the pure complexes has been resolved by co-coordination with trioctylphosphine oxide (TOPO), which permits complex concentrations of up to 5 × 10−3 mol L−1, at the same time maintaining complete transparency. Quantum efficiencies in excess of 60 % could thus be obtained for benzoyltrifluoroacetonates, and near 50 % for thenoyltrifluoroacetonates. These high efficiencies
have been confirmed by room-temperature life time measurements, which displayed straight single-exponential decay behavior for both complexes independent of their concentration in the silicone.
Key words: Eu Chelates, Silicone, Luminescence, Hybrid