Spirofluorene-locked carbazole based multiple resonance thermally activated delayed fluorescence emitters for efficient solution-processed narrowband green OLEDs

Abstract

Two kinds of multiple resonance thermally activated delayed fluorescence emitters namely SpDCz and DSpDCz are developed for solution-processed narrowband green organic light-emitting diodes (OLEDs) by fusing spirofluorene-locked carbazole moieties in...

Position-dependent hexaarylbenzene AIEgens: synthesis, characterization and optical properties

“…Closer inspection of the emission spectra of the two luminogens in dilute THF solution reveals that the emission maximum of p -TPE-HAB ( λ em max = 402) is red-shifted relative to o -TPE-HAB ( λ em max = 387), which can be ascribed to the difference in the co-planarity in these two molecular systems due to the effects of the substituents, and twisted intramolecular charge transfer (TICT) state resulting in the different emission behavior. 31 In sharp contrast, distinct emission behaviors was observed for these two luminogens in the solid state compared to dilute solution. A large red-shift of p -TPE-HAB at 495 nm and o -TPE-HAB at 502 nm was recorded, respectively.…”

“…transfer (TICT) state resulting in the different emission behavior. 31 In sharp contrast, distinct emission behaviors was observed for these two luminogens in the solid state compared to dilute solution. A large red-shift of p-TPE-HAB at 495 nm and o-TPE-HAB at 502 nm was recorded, respectively.…”

Organoboron-based multiple-resonance emitters: synthesis, structure–property correlations, and prospects

“…11 and Table 11). 155–165 In most cases, the para -positions of the carbazole nitrogen atoms were pre-functionalised and used in the S N Ar-based one-pot borylation protocol. The highly functionalised carbazolyl subunits ( e.g.…”

Efficient narrowband bluish-green emitters derived from a double-carbazole-fused organoboron multiple resonance skeleton with internal-structure modification

“…32 Nevertheless, these approaches may also induce obvious LRCT contributions that can be detrimental to maintaining narrowband emissions. 33,34 To the best of our knowledge, there have been few investigations focusing on directly modifying the internal structure of the parent CzBN, although such derivatives could be taken as new MR backbones while retaining most of the active sites of the parent CzBN skeleton, thus being able to not only serve as emitters but also having potential as skeletons to derive more MR emitters by suitable decorations. Possible challenges include: their chemical syntheses may require different precursors and reaction conditions, and the variability in the MR backbones may affect the internal MR features, thus creating more uncertainty in the final performance of target emitters.…”