π‐Conjugated Dendrimers as Stable Pure‐Blue Emissive Materials: Photophysical, Electrochemical, and Electroluminescent Properties

Bigger, stronger, better : A family of giant π‐conjugated dendrimers has been developed as pure‐blue active materials for organic light‐emitting diodes. The dendrimer‐generation number has little effect on the photophysical, electrochemical, and EL properties, and device efficiency of G0 and G1 . The preliminary OLED devices achieve pure‐blue color with stable CIE chromaticity coordinates (0.16, 0.08) for both G0 and G1 . magnified image A family of giant π‐conjugated dendrimers has been developed as pure‐blue active materials for organic light‐emitting diodes (OLEDs). The investigation of their photophysical properties indicates that G0 and G1 exhibit almost the same absorption and PL spectra in dilute solutions and in thin films. The steric hindrance of the bulky dendrimers effectively prevents strong intermolecular interaction in the solid state, which effectively improves the emission spectral stability. Preliminary OLEDs fabricated with the configuration of ITO/PEDOT:PSS/PVK/dendrimer/TPBI/Ba/Al achieve a pure‐blue emission with stable CIE chromaticity coordinates (0.16, 0.08) for both G0 and G1 . These results indicate that G0 and G1 are promising blue‐light emitting materials with good stability. Such strategy provides us a platform to achieve pure‐blue emitting dendrimer‐like materials with high efficiency for use as OLEDs.