Blue organic light-emitting diodes with hybridized local and charge-transfer excited state realizing high external quantum efficiency

Abstract

Donor–spacer–acceptor (D–π–A) materials CAPI and CCAPI, with hybridized local and charge transfer (HLCT) emissive states, have been synthesized.

Realization of switching between TADF and HLCT emissions through modulation of the intramolecular charge transfer character

“…So the key issue is how to screen an appropriate electron acceptor to match with TPA and POZ to realize the respective HLCT and TADF emissions. So far, the reported HLCT molecules are mainly based on acceptor units, such as anthracene (AN), [43][44][45][46] acridine (AC), 47,48 and naphthothiadiazole (NZ). [49][50][51] To summarize the character of HLCT molecules with TPA as the donor (e.g.…”

Non-doped OLEDs based on tetraphenylethylene phenanthroimidazoles with negligible efficiency roll-off: effects of end group regulated stimulus responsive AIE luminogens

“…Phenanthroimidazoles, TPE-NPPB and TPE-APPB are freely soluble in dichloromethane, tetrahydrofuran, chloroform and hexane but they are poorly soluble in water, alcohol and acetonitrile. The photophysical properties of TPE-NPPB and TPE-APPB were studied in tetrahydrofuran using electronic spectroscopy (Figure 3, cm -1 M -1 ), 346nm (Ɛ max -28901.73 cm -1 M -1 )] which confirm the presence of effective charge transfer transitions in these materials [31,32].…”

Bipolar Molecules with Hybridized Local and Charge‐Transfer State for Highly Efficient Deep‐Blue Organic Light‐Emitting Diodes with EQE of 7.4% and CIEy ∼ 0.05

“…[24] The fast hRISC can effectively reduce triplet exciton concentration when current density increases, which ensures small efficiency roll-off for OLEDs. [25][26][27][28][29] A lot of jobs in this field have been reported and they are well reviewed by Ma et al very recently. [24,[30][31][32][33][34][35][36][37][38][39][40][41][42][43] Blue "hot exciton" materials are mostly focused on molecules containing phenanthroimidazole (PI) or Anthracene (An) segment and other kind of molecules are also investigated occasionally.…”