A large-scale deep-blue tetraphenylbenzene-bridged hybridized local and charge transfer fluorophore exhibiting small efficiency roll-off and low amplified spontaneous emission threshold

Abstract

Efficient and stable deep-blue organic luminescent materials are important but rare for the application in full-color display due to their intrinsic wide bandgap characteristics. Here, a high-performance deep-blue hybridized local...

Regulation of excited-state properties of dibenzothiophene-based fluorophores for realizing efficient deep-blue and HLCT-sensitized OLEDs

“…As shown in Scheme 1, the target compounds (PIS and CNPIS) were synthesized from the Suzuki-coupling procedure between dibenzo[b,d]thiophen-4-yl boronic acid (DBT-B) and 2-(4bromophenyl)-1-phenyl-1H-phenanthro [9,10-d]imidazole (PI-Br) and 4-(2-(4-bromophenyl)-1H-phenanthro [9,10-d]imidazol-1-yl)benzonitrile (CNPI-Br), where PI-Br and CNPI-Br were obtained based on different literature studies. [41][42][43] After purifying by vacuum sublimation, the structures of PIS and CNPIS were confirmed by NMR spectra and mass spectrometry. Their detailed synthesis and characterization are shown in the Experimental Section.…”

Exciplex-induced TADF, persistent RTP and ML in a host–guest doping system

“…Based on this mechanism, the singlet and triplet excitons were formed through the recombination of positive and negative charges at the interface, just like electroluminescence (EL). 46 Therefore, the TADF effect induced by the exciplex would also contribute much to the promotion of bright ML emission, as it could make full use of the excited state energy from both singlet and triplet excitons. Thus, the exciplex as a good platform to construct ML materials could also be well confirmed.…”

Simple excited-state modification toward a deep-blue hybridized local and charge-transfer (HLCT) fluorophore and non-doped organic light-emitting diodes

“…Great efforts have been made by both academia and industry; the third-generation high-efficiency and low-cost pure organic fluorescent materials including thermally activated delayed fluorescence (TADF), [6][7][8][9][10][11] triplet-triplet annihilation (TTA), [12][13][14][15] hybridized local and charge-transfer (HLCT), [16][17][18][19][20][21][22][23] and organic radical-based emitters 24,25 have been rapidly developed. However, the new synthesis methods and categories of stable luminescent radicals are very limited, and their emission wavelengths are confined to the red and near-infrared regions.…”