| Abstract
| - Two aryl-substituted red emitting pentacenes, 5,6,13,14-tetraphenylpentacene (asym-TPP) and 5,14-bis(2,6-dimethylphenyl)-6,13-diphenylpentacene (DMPDPP), have been prepared and spectroscopicallycharacterized. Guest−host films of pentacene derivatives dispersed in tris(quinolin-8-olato)aluminum(III)(Alq3) exhibit narrow red emission (λmax = 663−680 nm), indicative of efficient Förster energy transferfrom the Alq3 host to the guest molecules. Solid-state absolute photoluminescence quantum yields of thefilms were measured as a function of guest molecule concentration (ΦPL ∼20% at 0.20−0.50 mol %).Red light-emitting diodes based on the fluorescent DMPDPP yield external electroluminescence quantumefficiency (ηEL ∼1%) close to the theoretical limit.
- Asymmetrically 5,6,13,14-tetraaryl-substituted pentacenes are synthesized and characterized. Changing substituents on the pentacene backbone permits the fine tuning of their emission while maintaining relatively high photoluminescence quantum yields. Saturated red electroluminescent devices are fabricated by doping DMPDPP (5,14-bis(2,6-dimethylphenyl)-6,13-diphenylpentacene) in tris(quinolin-8-olato)aluminum(III) (Alq3).
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