ABSTRACT
The advanced highly internal efficient rare earth emitting complexes have been launched with their application in active layers of OLEDs. Besides the internal efficiency that theoretically can be about 100 percent, the relative simple (and low cost) chemical synthesis allied with the novel simple device structure make these complexes very attractive. In addition, the relative “quasi-monochromatic” emission, typical of rare earth coordinated ions, definitely triggered the research on these materials. In this chapter, a wide overview to rare earth-based OLEDs is described from the chemical nature to the internal energy process mechanisms related with the specific nature of these emitting materials. The specific applications to active OLED layers are focused, addressing the benefits and assets, and also the common scientific barriers and difficulties to overcome for a further efficient technological application of these OLEDs.
