Emerging hyperfluorescent emitters for solid-state lighting

Abstract

This paper highlights the molecular design principles of hyperfluorescent emitters, their fundamental photophysics, and the advances of their applications in OLEDs.

Structural Optimization of BODIPY Derivatives: Achieving Stable and Long-Lived Green Emission in Hyperfluorescent OLEDs

“…Among the reported emitters as FD, the boron-dipyrromethene (BODIPY)-based fluorophores grabbed the interest due to their excellent photophysical properties, including high photoluminescence quantum yield (PLQY), narrow emission spectra, and high photo- and thermal stability. ,− However, their molecular planarity often causes an “aggregation caused quenching” (ACQ) effect in the solid states leading to luminance loss compared to that in dilute solution. − Such undesirable properties were addressed by increasing the intermolecular distances with peripheral bulky aryl- or alkyl-unit substitution on the dipyrrin core. In the quest for long-lived pure green OLEDs, Zhang et al developed a BODIPY derivative called tPhBODIPY by fusing a bulky m -(bis- t -butylphenyl) phenyl moiety at meso -position to suppress the ACQ effects in the solid states. , The tPhBODIPY showed a sharp emission at 518 nm with an fwhm of 28 nm.…”

Enhancement of Blue Doping-Free and Hyperfluorescent Organic Light Emitting Diode Performance through Triplet–Triplet Annihilation in the Derivatives of Anthracene and Carbazole

“…Anthracene-based emitters exhibiting TTA-related delayed fluorescence have attracted great interest over the last years. − Some of them have a carbazole moiety as a donor. , They are primarily used as emitters in OLEDs . A relatively new method for efficient harvesting of triplet excitons in OLEDs is based on hyperfluorescence. , TADF molecules are typically used as cohosts in organic hyperfluorescence systems . The hyperfluorescence approach allows us to achieve higher internal quantum efficiencies (IQEs) and EQEs for OLEDs than those for the devices based on prompt fluorescence .…”

“…32 A relatively new method for efficient harvesting of triplet excitons in OLEDs is based on hyperfluorescence. 33,34 TADF molecules are typically used as cohosts in organic hyperfluorescence systems. 35 The hyperfluorescence approach allows us to achieve higher internal quantum efficiencies (IQEs) and EQEs for OLEDs than those for the devices based on prompt fluorescence.…”