Chlorine effect on- electroluminescence of Tb complexes

Terbium complexes are known to be the green-light-emitting materials. Electroluminescent (EL) characteristics of terbium complexes containing phenanthroline (Phen) and 3-chlorophenanthroline (Cl-Phen) as a ligand were evaluated, where the device structure of ITO/TPD/Tb complexes/Alq3 or Bebq2/Li:Al was used. It was found that terbium complex containing Cl-Phen shows higher luminance efficiency compared to terbium complex containing Phen. Measurements of oxidation and reduction potential of these complexes have been carried out by using cyclic voltammetric method in order to explain the difference in luminance efficiency.