Enhancement of iridium-based organic light-emitting diodes by spatial doping of the hole transport layer
2005 (English)In: Applied Physics Letters, ISSN 0003-6951, Vol. 87, no 19, 193501- p.Article in journal (Refereed) Published
The electroluminescence efficiency of Ir-based green emitter devices is very sensitive to the nature of the hole transport layer used. We show that by inserting a 1 nm layer of bis[4-(N,N-diethylamino)-2-methylphenyl](4- methylphenyl)methane (MPMP) in a 4, 4′ - bis- (carbazol-9-yl) biphenyl (CBP) hole transport layer, a device that combines the positive attributes of both MPMP (high efficiency) and CBP (low injection voltage) is obtained. These results can be understood based on a combined ultraviolet photoemission spectroscopy/inverse photoemission spectroscopy study, which reveals the very low electron affinity and superior electron blocking capability of MPMP. © 2005 American Institute of Physics.
Place, publisher, year, edition, pages
2005. Vol. 87, no 19, 193501- p.
IdentifiersURN: urn:nbn:se:liu:diva-30235DOI: 10.1063/1.2117623Local ID: 15739OAI: oai:DiVA.org:liu-30235DiVA: diva2:251057