Extremely Efficient Indium-Tin-Oxide-Free Green Phosphorescent Organic Light-Emitting Diodes

Ames Laboratory-USDOE and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA.
Advanced Materials (Impact Factor: 15.41). 08/2012; 24(31):4337-42. DOI: 10.1002/adma.201202035
Source: PubMed

ABSTRACT This paper demonstrates extremely efficient (η(P,max) = 118 lm W(-1) ) ITO-free green phosphorescent OLEDs (PHOLEDs) with multilayered, highly conductive poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) films as the anode. The efficiency is obtained without any outcoupling-enhancing structures and is 44% higher than the 82 lm W(-1) of similar optimized ITO-anode PHOLEDs. Detailed simulations show that this improvement is due largely to the intrinsically enhanced outcoupling that results from a weak microcavity effect.

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