The new approaches to construct deep blue aggregation-induced emission （ALE） materials have been explored, which control the conjugation by two different strategies, to make a great step for the commercialization of...The new approaches to construct deep blue aggregation-induced emission （ALE） materials have been explored, which control the conjugation by two different strategies, to make a great step for the commercialization of organic light-emitting diodes. In order to shorten the intramolecular conjugation length, triphenylethylene （tPE） was utilized to construct blue AIEgens as peripheral groups, instead of tetraphenylethylene （TPE）, the famous AIE star molecule, to yield three blue AIEgens of 3,4-BtPE-PI, 4,4- BtPE-PI and 4,4-BtPE-PPI. Nondoped electroluminescence devices are fabricated by using these three AIEgens as the emitting material layer, the best performance of 3.8 cd/A as the maximum current efficiency achieved at the commission internationale de l＇Eclairage coordinates of （0.17, 0.18）.展开更多
Thermally activated delayed fluorescence(TADF)organic light-emitting diodes(OLEDs)have been demonstrated in applications such as displays and solid-state lightings.However,weak stability and ineffi-cient emission of b...Thermally activated delayed fluorescence(TADF)organic light-emitting diodes(OLEDs)have been demonstrated in applications such as displays and solid-state lightings.However,weak stability and ineffi-cient emission of blue TADF OLEDs are two key bottlenecks limiting the development of solution processable displays and white light sources.This work presents a solution-processed OLED using a blue-emitting TADF small molecule bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone(DMAC-DPS)as an emitter.We comparatively investigated the effects of single host poly(Nvinylcarbazole)(PVK)and a co-host of 60%PVK and 30%2,2′-(1,3-phenylene)-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole](OXD-7)on the device performance(the last 10%is emitter DMAC-DPS).The co-host device shows lower turn-on voltage,similar maximum luminance,and much slower external quantum efficiency(EQE)rolloff.In other words,device stability improved by doping OXD-7 into PVK,and the device impedance simultaneously and significantly reduced from 8.6103 to 4.2103 W at 1000 Hz.Finally,the electroluminescent stability of the co-host device was significantly enhanced by adjusting the annealing temperature.展开更多
基金supported by the National Natural Science Foundation of China (21325416 and 51573140)the National Basic Research Program of China (2013CB834701)
文摘The new approaches to construct deep blue aggregation-induced emission （ALE） materials have been explored, which control the conjugation by two different strategies, to make a great step for the commercialization of organic light-emitting diodes. In order to shorten the intramolecular conjugation length, triphenylethylene （tPE） was utilized to construct blue AIEgens as peripheral groups, instead of tetraphenylethylene （TPE）, the famous AIE star molecule, to yield three blue AIEgens of 3,4-BtPE-PI, 4,4- BtPE-PI and 4,4-BtPE-PPI. Nondoped electroluminescence devices are fabricated by using these three AIEgens as the emitting material layer, the best performance of 3.8 cd/A as the maximum current efficiency achieved at the commission internationale de l＇Eclairage coordinates of （0.17, 0.18）.
基金the National Key Research and Development Program of China(No.2017YFB0404404)the Open Fund of State Key Laboratory of Luminescent Materials and Devices(South China University of Technology),China。
文摘Thermally activated delayed fluorescence(TADF)organic light-emitting diodes(OLEDs)have been demonstrated in applications such as displays and solid-state lightings.However,weak stability and ineffi-cient emission of blue TADF OLEDs are two key bottlenecks limiting the development of solution processable displays and white light sources.This work presents a solution-processed OLED using a blue-emitting TADF small molecule bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone(DMAC-DPS)as an emitter.We comparatively investigated the effects of single host poly(Nvinylcarbazole)(PVK)and a co-host of 60%PVK and 30%2,2′-(1,3-phenylene)-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole](OXD-7)on the device performance(the last 10%is emitter DMAC-DPS).The co-host device shows lower turn-on voltage,similar maximum luminance,and much slower external quantum efficiency(EQE)rolloff.In other words,device stability improved by doping OXD-7 into PVK,and the device impedance simultaneously and significantly reduced from 8.6103 to 4.2103 W at 1000 Hz.Finally,the electroluminescent stability of the co-host device was significantly enhanced by adjusting the annealing temperature.
