A solution-processable hybridized local and charge-transfer (HLCT) phenanthroimidazole as a deep-blue emitter for efficient solution-processed non-doped electroluminescence device

An efficient solution-processable non-doped hybridized local and charge-transfer (HLCT) emitter for a simplified organic light-emitting diode

“…However, the decrease in the efficiency of this OLED at every high brightness could be accountable to its simple-structured device, which could cause the leak of the charge from the emissive layer, and an imperfect charge carrier balance in the device. 77,78 Comprehensively, this PBzFC-based bilayer device performance represents one of the best results of solutionprocessed HLCT-based OLEDs reported to date (Table S1, ESI †), [36][37][38][39]79 and is comparable to the EL performance of the thermal evaporated multiple layered OLED of its paternal HLCT molecule 4-(4-(carbazol-9-yl)phenyl)-7-phenylbenzothiadiazole (CzP-BZP) (EQE max = 6.95%). 25 To further study the utilization of excitons in the EL process, the exciton utilization efficiency (EUE) was calculated using EUE = EQE/(Z out  Z rec  F PL ), [80][81][82] Fig.…”

“…However, all of them were fabricated by thermal vacuum deposition, involving heating a solid material inside a high vacuum chamber at high temperatures and in a small area which is not applicable for fabricating flexible and large area-size devices and scaling up for commercial applications. To this point, there are only a few examples of solution-processed HLCT-based OLED devices (Table S1, ESI †), [36][37][38][39] and their EL performances are still inferior compared to their related thermal evaporated ones. 38,40 Hence, this work presents the design, synthesis, and properties of a high solid-state fluorescent molecule, namely CPBzFC (Scheme 1), bearing a combination of an HLCT feature and solution processability as an efficient non-doped emitter for a simple solution-processed OLED.…”

Chrysene-Cored Fluorescent Dendrimers as Nondoped Deep-Blue Emitters for Solution-Processable Electroluminescent Devices

“…The decent hole-transporting mobility of both compounds might be beneficial in a high-performance OLED device, because greater charge transport through the emitter could provide a wider recombination zone and might lead to longer device lifetimes as well as lower driving voltages. 6d…”

Impact of peripheral groups on pyrimidine acceptor-based HLCT materials for efficient deep blue OLED devices

“…Subsequently, a series of light-emitting molecules based on PPI were reported by changing the substituents at the 1 and 2 positions of imidazole. 3,[6][7][8][9][10][11][12][13][14][15][16][17][18] However, the class of PPI acceptors is relatively single, significantly limiting the development of such materials. Although some other acceptors, 19 such as pyrene-imidazole 20,21,[22][23][24] and 9,10-diphenylimidazole, [25][26][27] have been developed, there is still a need to develop more effective acceptor planes for expanding this HLCT material system.…”