Exciplex are generated at the heterojunction interface of electron donor and acceptor materials. Exciplex strategy can, thus, reduce molecular design difficulties for obtaining near-UV emission by selecting the appropriate electron donors and acceptors. Induced exciplex of Tris(4-carbazoyl-9-ylphenyl)amine (TCTA)/ 2,9-Dimethyl-4,7-diphenyl-1,10- phenanthroline (BCP) were applied to design deep blue organic light emitting diodes (OLEDs). BCP was used as an electron transport material and TCTA as a hole transporting material. The investigations carried out on planar-heterojunction have shown that recombination region was located at the vicinity of TCTA/BCP interface leading to exciplex formation. Furthermore, the thicknesses of BCP and TCTA layers play a key role in the control of the recombination zone and the emission color of the OLEDs. The electroluminescent spectra of planar-heterojunction exciplex-based OLEDs displayed deep blue emission at 423 nm with CIE coordinate of (0.16, 0.11). The emission of bulk-heterojunction exciplex-based OLEDs are also investigated showing that their emission is dominated by electroplex emission. The results demonstrate the feasibility of fabricating the efficient exciplex-based deep-blue OLED.
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