Synthesis, morphology and optoelectronic properties of tris[(N-ethylcarbazolyl)(3′,5′-hexyloxybenzoyl)methane](phenanthroline)-europium

The complex tris[1(N- ethylcarbazolyl)(3',5'-hexyloxybenzoyl)methane](phenanthroline)europium 1 incorporates a phenanthroline ligand for electron transport and a carbazole fragment in the diketonate ligand for hole transport; furthermore, the six hexyloxy groups prevent crystallization and allow for the formation of transparent clear films directly from solution; the photoluminescence from films of 1 is nearly monochromatic, characteristic of the europium ion and proceeds with an efficiency of 50(3)%; light emitting diodes(LEDs) were fabricated using the simplest possible device architecture comprising an anode (ITO), a layer of 1 and a cathode (Ca); a second LED configuration with a PVK layer on top of the ITO was also investigated; the performance of the two types of devices is discussed.