Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(...Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(CH_(3))_(2)NH_(2)][Zn_(3)(bbip)(BTDI)1.5(OH)]·DMF·MeOH·3H_(2)O}n(JXUST-13, bbip = 2,6-bis(benzimidazol-1-yl)pyridine and H_(4)BTDI = 5,5-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid)with new 4,4,8-connceted topology has been successfully synthesized and structurally characterized. Importantly, JXUST-13 could recognize H_(2)PO_(4)-and acetylacetone(Acac) by obvious fluorescence blue shift and slight enhancement with the detection limits of 2.70 μmol/L and 0.21 mmol/L, respectively. In addition, JXUST-13 exhibits relatively good thermal stability, chemical stabilities as well as reusability, and the analytes could be distinguished by naked eye and fluorescence test paper. Remarkably, JXUST-13 is the first dual-responsive MOF sensor based on fluorescence blue shift for the detection of H_(2)PO_(4)-and Acac with good selectivity in a handy, economic, and environmentally friendly manner.展开更多
By melting tetraphenylethene (TPE) and 1,2,4,5-tetraphenyl-lH-imidazole (TPI) units together through different linking positions, three new fluorophores are synthesized, and their optical, electronic and electro- ...By melting tetraphenylethene (TPE) and 1,2,4,5-tetraphenyl-lH-imidazole (TPI) units together through different linking positions, three new fluorophores are synthesized, and their optical, electronic and electro- luminescence (EL) properties are fully studied. Owing to the presence of TPE unit(s), these fluorophores are weak emitters in solutions, but are induced to emit strongly in the aggregated state, presenting typical aggregation-induced emission characteristics. The experimental and computational results reveal that different connection patterns between TPE and TPI could impact the molecular conjugation greatly, leading to varied emission wavelength, fluorescence quantum yield and EL performance in organic light emitting diodes (OLEDs). The fluorophore built by attaching TPE unit to the 1-position of imidazole ring shows bluest fluorescence, and its EL device emits at deep blue region (445 nm; CIE= (0.16, 0.15)). And the device based on the fluorophore by linking TPE to the 2- position of imidazole ring shows EL at 467 nm (CIE= (0.17, 0.22)) with good efficiencies of 3.17 cd.A ^-1, and 1.77%.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 (Nos. 22061019, 21861018, 22161019 and 12174172)the NSF of Jiangxi Province (No. 20202ACBL213001)+4 种基金Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry(No. 20212BCD42018)Fujian Key Laboratory of Functional Marine Sensing Materials,Minjiang University (No. MJUKF-FMSM202010)the Youth Jinggang Scholars Program in Jiangxi Province (No.QNJG2019053)the Two Thousand Program in Jiangxi Province (No.jxsq2019201068)the Special Foundation for Postgraduate Innovation in Jiangxi Province (No. YC_(2)020-B155)。
文摘Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(CH_(3))_(2)NH_(2)][Zn_(3)(bbip)(BTDI)1.5(OH)]·DMF·MeOH·3H_(2)O}n(JXUST-13, bbip = 2,6-bis(benzimidazol-1-yl)pyridine and H_(4)BTDI = 5,5-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid)with new 4,4,8-connceted topology has been successfully synthesized and structurally characterized. Importantly, JXUST-13 could recognize H_(2)PO_(4)-and acetylacetone(Acac) by obvious fluorescence blue shift and slight enhancement with the detection limits of 2.70 μmol/L and 0.21 mmol/L, respectively. In addition, JXUST-13 exhibits relatively good thermal stability, chemical stabilities as well as reusability, and the analytes could be distinguished by naked eye and fluorescence test paper. Remarkably, JXUST-13 is the first dual-responsive MOF sensor based on fluorescence blue shift for the detection of H_(2)PO_(4)-and Acac with good selectivity in a handy, economic, and environmentally friendly manner.
文摘By melting tetraphenylethene (TPE) and 1,2,4,5-tetraphenyl-lH-imidazole (TPI) units together through different linking positions, three new fluorophores are synthesized, and their optical, electronic and electro- luminescence (EL) properties are fully studied. Owing to the presence of TPE unit(s), these fluorophores are weak emitters in solutions, but are induced to emit strongly in the aggregated state, presenting typical aggregation-induced emission characteristics. The experimental and computational results reveal that different connection patterns between TPE and TPI could impact the molecular conjugation greatly, leading to varied emission wavelength, fluorescence quantum yield and EL performance in organic light emitting diodes (OLEDs). The fluorophore built by attaching TPE unit to the 1-position of imidazole ring shows bluest fluorescence, and its EL device emits at deep blue region (445 nm; CIE= (0.16, 0.15)). And the device based on the fluorophore by linking TPE to the 2- position of imidazole ring shows EL at 467 nm (CIE= (0.17, 0.22)) with good efficiencies of 3.17 cd.A ^-1, and 1.77%.
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.