Organic light emitting devices based on exciplex interaction from blends of charge transport molecules

✍ Scribed by Jihua Yang; Keith C. Gordon

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 197 KB
• Volume: 375
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/s0009-2614(03)00950-3

✦ Synopsis

Exciplex electroluminescence of indium-tin-oxide glass (ITO)/poly(N-vinylcarbazole)(PVK):N,N 0 -diphenyl-N,N 0bis(3-methylphenyl)-[1,1 0 -biphenyl]-4,4 0 -diamine(TPD):2,5-bis (5-tert-butyl-2-benzoxazolyl) thiophene (BBOT)/Al devices have been investigated in comparison with ITO/PVK:BBOT/Al device. While the ITO/PVK:BBOT/Al device shows emission dominated by exciplex interaction of PVK with BBOT, the ITO/PVK:TPD:BBOT/Al devices show emission color adjustable by the hybrid exciplex interaction of TPD with BBOT, and this exciplex becomes the primary recombination center at a critical TPD doping concentration. The device efficiency can be improved markedly by incorporating hole transporting poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) and electron transporting 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)/tris-(8-hydroxyquinoline) aluminum (Alq 3