Synthesis and properties of europium complexes with β-diketone ligands for organic electroluminescent devices

Europium complexes with new beta-diketone ligands with fluorene for organic electroluminescent (EL) devices have been synthesized and their properties examined. The absorption spectra of the complexes were varied by changing the conjugated system of the beta-diketone; also, the energy transfer from the host material to the europium complexes and the intramolecular energy transfer have been improved. Concerning the volatility, the thermal properties of the europium complexes were improved by using phenanthroline derivatives. We fabricated organic EL devices using the synthesized complexes, and investigated the luminance of the devices.