Oligoarylenes end-capped with carbazol-N-yl-carbazole as color tunable light-emitting and hole-transporting materials for solution-processed OLEDs

Abstract

A series of oligoarylenes end-capped with carbazol-N-yl-carbazole (CAr) were synthesized and characterized as color tunable light-emitting materials. Their photophysical, thermal, electrochemical, and electroluminescent properties as non-doped solution processed emitters and hole-transporters for OLEDs were investigated. They exhibited a bright blue to red fluorescence with hole-transporting properties and could form morphologically stable amorphous thin films. Simple structured solutionprocessed CAr-based OLEDs emitted stable colors spanning the entire visible spectrum (blue, light blue, green, yellow and red) with luminance efficiencies up to 13.73 cd A À1 . The CIE coordinates of the emitted colors were (0.67, 0.33) for red, (0.30, 0.61) for green and (0.19, 0.18) for blue, which are close to the pure red, green and blue colors. A solution-processed white OLED fabricated with a mixture of CAr radiated a white light with a luminance efficiency of 1.49 cd A À1 at 4.7 mA cm À2 and CIE coordinates of (0.33, 0.35). † Electronic supplementary information (ESI) available: Synthesis of 1-5, quantum chemical calculation results, multiple scan CV plots, AFM images, EL spectra of the OLEDs and 1 H NMR and 13 C NMR spectra. See

Efficient bifunctional materials based on pyrene- and triphenylamine-functionalized dendrimers for electroluminescent devices

“…10 However, a weakness of pyrene is that its emission in the solid state is effectively suppressed due to the formation of excimers via p-p stacking. 11 Numerous efforts have been attempted to improve the photophysical properties of pyrene such as 3,6-dipyrenylcarbazole end capped oligouorenes, 12 tetraarylpyrenes 13 and 9,9-bis-(3-(9phenyl-carbazoyl))-2,7-dipyrenyluorene, 14 pyrene-1,3-alt-calix [4] arene, 15 uorene-substituted pyrenes, 16 2,7-bispyrene-9,9-bis(4diphenylaminophenyl)uorenes, 17 pyrene-modied carbazole oligomers 18 and pyrene functionalized octavinylsilsesquioxane cores. 19 In terms of the device fabrication, solution-processed OLEDs fabricated using molecular amorphous materials will have great advantages, because the materials used are easy to synthesize and purify, while the fabrication method is convenient, low cost and allows large-scale manufacturing with less material usage.…”

Synthesis of Amorphous Monomeric Glass Mixtures for Organic Electronic Applications

“…The processability of these materials is key for their viability in various applications. , Both 1 and 2 are readily soluble in organic solvents (e.g., dichloromethane, tetrahydrofuran, chloroform, and acetonitrile), which makes them amenable to solution processing. Additionally, both 1 and 2 can be thermally deposited as thin films, which is a major advantage over polymeric systems and is important for OLED applications. , …”