A π-Stacked and conjugated hybrid based on poly(N-vinylcarbazole) Postfunctionalized with terfluorene for stable deep-blue hole-transporting materials

The combination of π-stacked with π-conjugated building blocks offers an essential strategy to construct multifunctional organic semiconductors (MOSs) with the unique optoelectrical properties. Covalent hybrids can efficiently avoid the intrinsic phase-separation defects in corresponding blend system. In this contribution, poly(vinylcarbazole) tethered with terfluorene, PVK-TF, as a double-channeled πstacked and π-conjugated hybrid (SCH), has been constructed via Friedal-Crafts click postmodification (FCCP). The chemical structure and optoelectrical property were determined by GPC, UV-vis, PL, TGA, DSC, and CV Its PL spectra in the annealing thin film at N2 atmosphere without low-energy emission bands centered at the 530 nm indicates that no π-stacks between carbazole and TF or among TFs dominate the whole condensed phase, which is in agreement with the intrachain T-shaped π-pitched motifs in molecular modeling simulation due to steric hindrance effect in complicated diarylfluorenes (CDAFs). A supporting prototype stable deep-blue PLED was successfully obtained with an Internationale de l'Eclairage (CIE) coordinates of (0.20, 0.10) and a width at half maximum (FWHM) of about 60 nm at high current density of 100 mA/cm² (35 V). Deep-blue PVK-TF is a promising MOS for hole-transporting and host materials.