Non-doped, blue-emitting, color-stable, organic light-emitting diode based on 2,2′:6′,2″-ternaphthalene

A novel non-doped blue-emitting material, 2,2′:6′,2″-ternaphthalene (NNN), which is based on three naphthalene units forming a rodlike molecule, has been synthesized and characterized. Organic light-emitting diodes based on NNN as emitter exhibit blue emission with Commission Internationale de l’Eclairage color coordinates of x = 0.18 and y = 0.11. In addition, the morphology and crystallographic structure of the NNN thin films has been investigated. NNN deposited on poly[3,4-(ethylenedioxy) thiophene]:poly (styrene sulfonate) on Indium Tin Oxide-covered glass forms crystalline structures of high crystallographic quality. The molecules are aligned almost perpendicular to the substrate surface and exhibit a tilt angle of 23 ∘ .