Studies of the electro-oxidation of carbazole layer in protic acid media with a view to developing light-emitting diodes

Electro-oxidation has been used for fabricating thin film tetracarbazole fo r organic light-emitting diode applications. The experimental parameters gr eatly influence the physical aspect of the tetramer surface. FTIR measureme nts reveal that the oligomer is a 3,3'-tetracarbazole (4Cz). Elemental anal ysis shows that the film is doped by perchloric acid, and contained methano l and water. Impedance spectroscopy indicates that ionic and electronic dif fusions increase in the 4Cz film during its formation. When excited by UV l ight, the tetramer emits blue light. (C) 2001 Society of Chemical Industry.