Pure near-infrared(NIR)phosphorescent materials with emission peak larger than 700 nm are of great significance for the development of optoelectronics and biomedicine.We have designed and synthesized two new B-embedde...Pure near-infrared(NIR)phosphorescent materials with emission peak larger than 700 nm are of great significance for the development of optoelectronics and biomedicine.We have designed and synthesized two new B-embedded pure near-infrared(NIR)-emitting iridium complexes(Ir(Bpiq)2acac and Ir(Bpiq)2dpm)with peaks greater than 720 nm.More importantly,they exhibit very narrow phosphorescent emission with full width at half maximum(FWHM)of only about 50 nm(0.12 e V),resulting in a high NIR content(>90%)in their spectrum.In view of better optical property and solubility,the complex Ir(Bpiq)_(2)dpm was used as the emitting layer of a solution-processed OLED device,and achieved good maximum external quantum efficiency(EQE)(2.8%)peaking at 728 nm.This research provides an important strategy for the design of narrowband NIR-emitting phosphorescent iridium complexes and their optoelectronic applications.展开更多
In recent years,host-vip interactions of macrocycles have emerged as a promising approach to effectively enhance pure organic room-temperature phosphorescence by inhibiting the nonradiative relaxation while isolatin...In recent years,host-vip interactions of macrocycles have emerged as a promising approach to effectively enhance pure organic room-temperature phosphorescence by inhibiting the nonradiative relaxation while isolating the effects of oxygen and water molecules.In this work,a supramolecular assembly Q[8]-BCPI was constructed by 6-bromoisoquinoline derivative(BCPI)and cucurbit[8]uril(Q[8]).The assembly produced intense green room temperature phosphorescence(RTP)emission and enabled supramolecular recognition and detection of L-tryptophan(L-Trp)and L-tyrosine(L-Tyr).Moreover,the Q[8]-BCPI assembly showed good biocompatibility and low biotoxicity,and had a good staining effect on HeLa cells.展开更多
Achieving versatile room temperature phosphorescence(RTP)materials,especially with tunable mechanical properties and shape memory is attractive and essential but rarely reported.Here,a strategy was reported to realize...Achieving versatile room temperature phosphorescence(RTP)materials,especially with tunable mechanical properties and shape memory is attractive and essential but rarely reported.Here,a strategy was reported to realize multi-functional RTP films with multicolor fluorescence,ultralong afterglow,adjustable mechanical properties,and shape memory through the synergistic dynamic interaction of lanthanide(Ln~Ⅲ)-terpyridine coordination,borate ester bonds,and hydrogen bondings in a poly(vinyl alcohol)(PVA)matrix.By varying the amount of borax,the mechanical properties of the films could be finely controlled due to the change of crosslinking degree of dynamic borate ester bonds in PVA.The assembly and disassembly of borate ester bonds upon the trigger of borax and acid were applied as reversible linkage to achieve programmable shape memory behavior.In addition,the films displayed both fascinating multicolor fluorescence and ultralong afterglow characteristics due to the presence of Ln III doping and confinement of terpyridine in PVA.This study provides a new avenue to impart modulable mechanical strength and shape memory to RTP materials.展开更多
A cyclometalated greenish-yellow emitter 2,3-diphenylimidazo[1,2-a]pyridine iridium（Ill） complex is successfully synthesized and used to fabricate phosphorescent organic light-emitting diodes. The optimized device e...A cyclometalated greenish-yellow emitter 2,3-diphenylimidazo[1,2-a]pyridine iridium（Ill） complex is successfully synthesized and used to fabricate phosphorescent organic light-emitting diodes. The optimized device exhibits a greenish-yellow emission with the peak at 523nm and a strong shoulder at 557nm, corresponding to Commission Internationale de l＇Eclairage coordinates of （0.38, 0.68）. The full width at half maximum of the device is 93 nm, which is broader than the fac-tris（2-phenylpyridine）iridium [Ir（ppy）3] based reference device of 78 nm. Meanwhile, a maximum current efficiency of 62.6 cd/A （47.51m/W） is obtained. This result is higher than a maximum current efficiency of 54.8 cd/A （431m/W） of the Ir（ppy）a based device. The results indicate that this new iridium complex may have potential applications in fabricating high color rendering index white organic light emitting diodes.展开更多
Several highly efficient iridium-complex polymer light-emitting devices （PLEDs） are fabricated, with a newly synthesized blue conjugated polymer, poly[（9,9-bis（4-（2-ethylhexyloxy）phenyl）-fluorene）-co-（3,7-dib...Several highly efficient iridium-complex polymer light-emitting devices （PLEDs） are fabricated, with a newly synthesized blue conjugated polymer, poly[（9,9-bis（4-（2-ethylhexyloxy）phenyl）-fluorene）-co-（3,7-dibenziothiene-S,S- dioxide15）] （PPF-3,TSO15）, chosen as host. High luminous efficiencies of 7.4 cd.A-1 and 27.4 cd.A-1 are achieved in red and green PLEDs, respectively, by optimizing the doping concentrations of red phosphorescent dye iridium bis（1- phenylisoquinoline） （acetylacetonate） （Ir（piq）） and green phosphorescent dye iridium tris（2-（4-tolyl）pyridinato-N, C2＇） （Ir（mppy）3）.Furthermore, highly efficient white PLEDs （WPLEDs） with the Commission Internationale de l＇Eclairage （CIE） coordinates of （0.35, 0.38） are successfully produced by carefully controlling the doping concentration of the irid- ium complex. The obtained WPLEDs show maximal efficiencies of 14.4 cd.A-1 and 10.1 lm.W-1, which are comparable to those of incandescent bulbs. Moreover, the electroluminescent spectrum of the white device with an initial luminance of about 1000 cd.m-2 is stable, subject to constant applied current stress, indicating that good device stability can be obtained in this system.展开更多
The red long-lasting phosphorescent （LLP） of β-Zn3（POa）2：Mn2＋,pr3＋ material was prepared through combustion and conventional solid-state sintering methods. The influence of Pr3＋ ions on luminescence and LLP o...The red long-lasting phosphorescent （LLP） of β-Zn3（POa）2：Mn2＋,pr3＋ material was prepared through combustion and conventional solid-state sintering methods. The influence of Pr3＋ ions on luminescence and LLP of Mn2＋ in 13-Zn3（POa）2：Mn2＋,pr3＋ phosphor was systematically investigated. The phosphor presented a strong photoluminescence peak at 620 nm attributed to the 4T1g→ 6A1 g transition of Mn2＋ ions in octahedral coordination. Red LLP was observed in β-Zn3（PO4）2：Mn2＋,Pr3＋ phosphors with persistence time for more than 2 h. It was found that the long persistent phosphorescent performance of Mn2＋ such as brightness and duration was improved by the energy transfer from Pr3＋ to Mn2＋ when Pr3＋ ions as sensitizers were doped into matrix. The fact that the TL peak at low temperature was largely enhanced in Mn2＋, Pr3＋ codoped ^-Zn3（PO4）2 phosphor showed the significant increase of defect concentration with suitable depth. There existed two factors working together to be responsible for the enhancement of LLP performance in β-Zn3（PO4）2：Mn2＋,Pr3＋.展开更多
Organic optoelectronic integrated devices（OIDs） with ultraviolet（UV） photodetectivity and different color emitting were constructed by using a thermally activated delayed fluorescence（TADF） material 4, 5-bis（ca...Organic optoelectronic integrated devices（OIDs） with ultraviolet（UV） photodetectivity and different color emitting were constructed by using a thermally activated delayed fluorescence（TADF） material 4, 5-bis（carbazol-9-yl）-1, 2-dicyanobenzene（2 CzPN） as host. The OIDs doping with typical red phosphorescent dye [tris（1-phenylisoquinoline）iridium（Ⅲ）, Ir（piq）3], orange phosphorescent dye {bis[2-（4-tertbutylphenyl）benzothiazolato-N,C-（2＇）]iridium（acetylacetonate）,（tbt）2 Ir（acac）}, and blue phosphorescent dye [bis（2, 4-di-fluorophenylpyridinato）-tetrakis（1-pyrazolyl）borate iridium（Ⅲ）, FIr6] were investigated and compared. The（tbt）2 Ir（acac）-doped orange device showed better performance than those of red and blue devices, which was ascribed to more effective energy transfer. Meanwhile, at a low dopant concentration of 3 wt.%, the（tbt）2 Ir（acac）-doped OIDs showed the maximum luminance, current efficiency, power efficiency of 70786 cd/m^2, 39.55 cd/A, and 23.92 lm/W, respectively, and a decent detectivity of 1.07 × 10^11 Jones at a bias of -2 V under the UV-350 nm illumination. This work may arouse widespread interest in constructing high efficiency and luminance OIDs based on doping phosphorescent dye.展开更多
2,7-Di（9,9-dimethyl-9H-fluoren-l-yl）-9H-thioxanthen-9-one （DMBFTX） with thermally activated delayed fluorescence （TADF） was well designed and synthesized. The phosphorescent organic lightemitting device （PHOLED...2,7-Di（9,9-dimethyl-9H-fluoren-l-yl）-9H-thioxanthen-9-one （DMBFTX） with thermally activated delayed fluorescence （TADF） was well designed and synthesized. The phosphorescent organic lightemitting device （PHOLED） based on this novel TADF host material displays a stable red phosphorescence region, a peak external quantum efficiency （EQE） value of 12.9% and a low EQE roll-off of 38.8%at a luminance of 10000 cd/m2, which is benefited from the reverse intersystem crossing （RISC） of TADF host and less populated triplet exitons. Notably, the red device based on the TADF host DMBFrX exhibits superior electroluminescence performance and reduced efficiency roll-offcompared with the one hosted by commercially available host 1,3-bis（9-carbazolyl）benzene （mCP）, illustrating the high potential of employing the TADF host material with small energy gap to reduce efficiency roll-off in PHOLED.展开更多
Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors ...Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work,a series of mononuclear gold(Ⅰ) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(Ⅰ)-containing complexes. In addition, these phosphors display typical aggregation-induced emission(AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.展开更多
A series of green phosphorescent organic light-emitting diodes based on bipolar-transporting material 4,4Lbis- （carbazol-9-yl） biphenyl （CBP） are prepared. We insert a mixed host emitting interlayer （CBPx： elect...A series of green phosphorescent organic light-emitting diodes based on bipolar-transporting material 4,4Lbis- （carbazol-9-yl） biphenyl （CBP） are prepared. We insert a mixed host emitting interlayer （CBPx： electron- transporting material 1,3,＆tris （N-phenylbenzimidazole-2yl） （TPBi）1-X） in the middle of the emitting layer, and the best performance appears when x is 2/3. The position of this interlayer can also affect the performanee of phosphorescent organic light-emitting diodes. When this interlayer is close to the side of the electron transporting layer, the maximum value of luminance, the current efficiency and the power efficiency are 34090cd/m2 at 12 V, 60. 6 cd/A and 56.6 lm/W, respectively.展开更多
We fabricated phosphorescent organic light-emitting diodes(Ph OLEDs) using thermally activated delayed fluorescence(TADF) material 10,10’-(4,4’-sulfonylbis(4,1-phenylene)) bis(9,9-dimethyl-9,10-dihydroacridine)(DMAC...We fabricated phosphorescent organic light-emitting diodes(Ph OLEDs) using thermally activated delayed fluorescence(TADF) material 10,10’-(4,4’-sulfonylbis(4,1-phenylene)) bis(9,9-dimethyl-9,10-dihydroacridine)(DMAC-DPS) with low concentration, which showed better performance compared with 1,3-bis(carbazole-9-yl) benzene(m CP) based devices. When the concentration of DMAC-DPS was 1 wt%, the driving voltage of the device was only 3.3 V at 1 000 cd/m2, and the efficiency and lifetime of the device were effectively improved compared with those of m CP based devices. The result indicated that DMAC-DPS could effectively improve the performance of phosphorescent devices. We believe that the better device performance can be attributed to the optimization of the energy transfer process in the emitter layer and lifetime of triplet excitons by DMAC-DPS. The study may provide a simple and effective strategy to achieve high-performance OLEDs.展开更多
A high-efficiency green phosphorescent organic light emitting diode with a simplified structure is achieved that is free of a hole transport layer. The design of this kind of device structure not only saves the consum...A high-efficiency green phosphorescent organic light emitting diode with a simplified structure is achieved that is free of a hole transport layer. The design of this kind of device structure not only saves the consumption of organic materials but also greatly reduces the structural heterogeneities and effectively facilitates the charge injection into the emissive layer. The resulting green phosphorescent organic light-emitting diodes （PHOLEDs） exhibit higher electroluminescent efficiency. The maximum external quantum efficiency and current efficiency reach 23.7% and 88 cd/A, respectively. Moreover the device demonstrates satisfactory stability, keeping 23.7% and 88cd/A, 22% and 82cd/A, respectively, at a luminance of 100 and 1000cd/m2. The working mechanism for achieving high efficiency based on such a simple device structure is discussed correspondingly. The improved charge carrier injection and transport balance are proved to prominently contribute to achieve the high efficiency and great stability at high luminance in the green PHOLEDs.展开更多
Four novel polymers, poly（3,6-9-decyl-carbazole-alt-1,3-benzene） （PB13CZ）, poly（3,6-9-decyl-carbazole-alt- bis（4-phenyl） （phenyl） phosphine oxide） （PTPPO38CZ）, poly（3,6-9-decyl-carbazole-alt-2,4-phenyl（d...Four novel polymers, poly（3,6-9-decyl-carbazole-alt-1,3-benzene） （PB13CZ）, poly（3,6-9-decyl-carbazole-alt- bis（4-phenyl） （phenyl） phosphine oxide） （PTPPO38CZ）, poly（3,6-9-decyl-carbazole-alt-2,4-phenyl（diphenyl） phosphine oxide） （PTPPO13CZ） and poly（3,6-9-decyl-carbazole-alt-bis（3-phenyl） （phenyl） phosphine oxide） （PTTPO27CZ） were synthesized, and their thermal, photophysical properties and device applications were further investigated to correlate the chemical structures with the photoelectric performance of bipolar host materials for phosphorescent organic light emitting diodes. All of them show high thermal stability as revealed by their high glass transition temperatures and thermal decomposition temperatures at 5% weight loss. These polymers have wide band gaps and relatively high triplet energy levels. As a result, the spin coating method was used to prepare the green phosphorescent organic light emitting diodes with polymers PTPPO38CZ, PTPPO13CZ and PTTPO27CZ as the typical host materials. The green device of polymer PTPPO38CZ as host material shows electroluminescent performance with maximum current efficiency of 2.16 cd.A-1, maximum external quantum efficiency of 0.7%, maximum brightness of 1475 cd.m-2 and reduced efficiency roll-off of 7.14% at 600 cd.m-2, which are much better than those of the same devices hosted by polymers PTTPO27CZ and PTPPO13CZ.展开更多
A novel phosphorescent cyclometalated platinum dimer with bis-[2-（p-dodecyloxyphenyl） pyridyll-hexane-1,6-diol as ligand and 1,3-（1-n-hexyl,3-n-heptadecyl）diketone as ancillary ligand was synthesized.The chemical ...A novel phosphorescent cyclometalated platinum dimer with bis-[2-（p-dodecyloxyphenyl） pyridyll-hexane-1,6-diol as ligand and 1,3-（1-n-hexyl,3-n-heptadecyl）diketone as ancillary ligand was synthesized.The chemical structure and liquid crystal property of the dimer were characterized by ~1H NMR,ESl-MS,polarizing optical microscopy（POM） and differential scanning calorimetry （DSC）.The aligned film of title compound on the rubbed polyimide film is intensely emissive at room temperature with emission maximum at 516nm.The luminescence dichroic ratio（（？） ） at 516 nm is 3.1.展开更多
Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red an...Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.展开更多
High-efficiency blue electrophosphorescent organic light-emitting devices employing MoO3 used as hole injection layer （HIL） and MoO3 doped N,N-dicarbazoly-3,5-benzene （mCP） as hole transport layer （HTL） were dem...High-efficiency blue electrophosphorescent organic light-emitting devices employing MoO3 used as hole injection layer （HIL） and MoO3 doped N,N-dicarbazoly-3,5-benzene （mCP） as hole transport layer （HTL） were demonstrated. The blue OLED with the novel anode structure and TAPC used as electron blocking layer show a low turn-on voltage of 2.4 V, a maximum power efficiency of 33.6 lm/W at 3.1 V and 25 lrn/W with 1 000 cd/m2 at 3.8 V. It is also found that the efficiency of the devices is dependent on the different EBL materials. This is may because of relationship with the charge mobility and the triplet energy level of EBL materials. The device efficiency is determined by the charge balance which plays an important role.展开更多
White organic light-emitting diodes were fabricated by using a novel phosphorescence bis（1,2-diphenyl-1H-benzoimidazole）iridium（acetylacetonate）[（pbi）2Ir（acac）] as sensitizer and a fluorescent dye of 4- （dicy...White organic light-emitting diodes were fabricated by using a novel phosphorescence bis（1,2-diphenyl-1H-benzoimidazole）iridium（acetylacetonate）[（pbi）2Ir（acac）] as sensitizer and a fluorescent dye of 4- （dicyanomethylene）-2-t-butyl-6-（1,1,7,7-tetramethyljulolidyl-9-enyl）-4H-pyran （DCJTB） codoped into a carbazole polymer of poly（N-vinylcarbazole） （PVK）. Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of （pbi）2Ir（acac） and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of （pbi）2Ir（acac） and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the vips enabled a strong yellow emission from （pbi）2Ir（acac） and DCJTB, where （pbi）2Ir（acac） plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N＇-diphenyl-N,N＇-bis（1- naphthyl）（1,1＇-biphenyl）-4,4＇-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1＇Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.展开更多
To elucidate the nature of low-lying triplet states and the effect of ligand modifica- tions on the excited-state properties of functional cationic iridium complexes, the solvent- dependent excited-state dynamics of t...To elucidate the nature of low-lying triplet states and the effect of ligand modifica- tions on the excited-state properties of functional cationic iridium complexes, the solvent- dependent excited-state dynamics of two phosphorescent cationic iridium（Ⅲ） complexes, namely [Ir（dph-oxd）2（bpy）]PF6 （1） and [Ir（dph-oxd）2（pzpy）]Pf6 （2）, were investigated by femtosecond and nanosecond transient absorption spectroscopy. Upon photoexcitation to the metal-to-ligand charge-transfer （MLCT） states, the excited-state dynamics shows a rapid process （τ-=0.7-3 ps） for the formation of solvent stabilized 3MLCT states, which significantly depends on the solvent polarity for both 1 and 2. Sequentially, a relatively slow process assigned to the vibrational cooling/geometrical relaxation and a long-lived phospho- rescent emissive state is identified. Due to the different excited-state electronic structures regulated by ancillary ligands, the solvation-induced stabilization of the 3MLCT state in 1 is faster than that in 2. The present results provide a better sight of excited-state relaxation dynamics of ligand-related iridium（Ⅲ） complexes and solvation effects on triplet manifolds.展开更多
Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. ...Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.展开更多
Room temperature phosphorescent(RTP)materials have a variety of applications ranging from bioimaging,optoelectronic devices to information security protection.However,the preparation procedures for these materials are...Room temperature phosphorescent(RTP)materials have a variety of applications ranging from bioimaging,optoelectronic devices to information security protection.However,the preparation procedures for these materials are always tedious and time-consuming.Here,we report a micro-wave approach to prepare RTP carbon dots(CDs)in only 8 min.The micro-wave promoted the carbon and boron bond formation using natural compounds glucose and boric acids.This result has been confirmed using TEM,FTIR,XPS and XRD measurements.The C-B hetero atomized material presented a long afterglow property.With the irradiation with UV light,we observed an eight-second RTP by naked eyes after the lamp was turned off,and the phosphorescence lifetime was 487 ms.This excellent performance was mainly due to the formation of B-C bonds that promoted the intersystem crossings(ISC)and non-radiation transition of triplet states.Moreover,the glass state of the materials also helped to stabilize the triplet states of B-CDs and made its non-irradiation inactivated,which resulted in the characteristics of yellow green RTP.These results have demonstrated that micro-wave is a convenient and effective strategy to make hetero atomized RTP material,providing new possibilities for their industrial productions.展开更多
基金support from the National Natural Science Foundation of China(Nos.22171109,52373195 and 22001097)Natural Science Foundation of Jiangsu Province of China(No.BK20201003)+1 种基金the Postdoctoral Research Foundation of China(No.2021M701657)the Opening Project of Key Laboratory of Optoelectronic Chemical Materials and Devices,Ministry of Education,Jianghan University(No.JDGD-202301)。
文摘Pure near-infrared(NIR)phosphorescent materials with emission peak larger than 700 nm are of great significance for the development of optoelectronics and biomedicine.We have designed and synthesized two new B-embedded pure near-infrared(NIR)-emitting iridium complexes(Ir(Bpiq)2acac and Ir(Bpiq)2dpm)with peaks greater than 720 nm.More importantly,they exhibit very narrow phosphorescent emission with full width at half maximum(FWHM)of only about 50 nm(0.12 e V),resulting in a high NIR content(>90%)in their spectrum.In view of better optical property and solubility,the complex Ir(Bpiq)_(2)dpm was used as the emitting layer of a solution-processed OLED device,and achieved good maximum external quantum efficiency(EQE)(2.8%)peaking at 728 nm.This research provides an important strategy for the design of narrowband NIR-emitting phosphorescent iridium complexes and their optoelectronic applications.
基金supported by the National Natural Science Foundation of China(No.22361011)Guizhou Provincial Science and Technology Projects(No.ZK[2023]General 040)。
文摘In recent years,host-vip interactions of macrocycles have emerged as a promising approach to effectively enhance pure organic room-temperature phosphorescence by inhibiting the nonradiative relaxation while isolating the effects of oxygen and water molecules.In this work,a supramolecular assembly Q[8]-BCPI was constructed by 6-bromoisoquinoline derivative(BCPI)and cucurbit[8]uril(Q[8]).The assembly produced intense green room temperature phosphorescence(RTP)emission and enabled supramolecular recognition and detection of L-tryptophan(L-Trp)and L-tyrosine(L-Tyr).Moreover,the Q[8]-BCPI assembly showed good biocompatibility and low biotoxicity,and had a good staining effect on HeLa cells.
基金supported by the National Natural Science Foundation of China(No.22205249)the Sino-German Mobility Program(No.M-0424)Ningbo International Cooperation Project(No.2023H019)。
文摘Achieving versatile room temperature phosphorescence(RTP)materials,especially with tunable mechanical properties and shape memory is attractive and essential but rarely reported.Here,a strategy was reported to realize multi-functional RTP films with multicolor fluorescence,ultralong afterglow,adjustable mechanical properties,and shape memory through the synergistic dynamic interaction of lanthanide(Ln~Ⅲ)-terpyridine coordination,borate ester bonds,and hydrogen bondings in a poly(vinyl alcohol)(PVA)matrix.By varying the amount of borax,the mechanical properties of the films could be finely controlled due to the change of crosslinking degree of dynamic borate ester bonds in PVA.The assembly and disassembly of borate ester bonds upon the trigger of borax and acid were applied as reversible linkage to achieve programmable shape memory behavior.In addition,the films displayed both fascinating multicolor fluorescence and ultralong afterglow characteristics due to the presence of Ln III doping and confinement of terpyridine in PVA.This study provides a new avenue to impart modulable mechanical strength and shape memory to RTP materials.
文摘A cyclometalated greenish-yellow emitter 2,3-diphenylimidazo[1,2-a]pyridine iridium（Ill） complex is successfully synthesized and used to fabricate phosphorescent organic light-emitting diodes. The optimized device exhibits a greenish-yellow emission with the peak at 523nm and a strong shoulder at 557nm, corresponding to Commission Internationale de l＇Eclairage coordinates of （0.38, 0.68）. The full width at half maximum of the device is 93 nm, which is broader than the fac-tris（2-phenylpyridine）iridium [Ir（ppy）3] based reference device of 78 nm. Meanwhile, a maximum current efficiency of 62.6 cd/A （47.51m/W） is obtained. This result is higher than a maximum current efficiency of 54.8 cd/A （431m/W） of the Ir（ppy）a based device. The results indicate that this new iridium complex may have potential applications in fabricating high color rendering index white organic light emitting diodes.
基金Project supported by the National Basic Research Program of China (Grant No. 2009CB623602)the National Natural Science Foundation of China (Grant No. U0634003)
文摘Several highly efficient iridium-complex polymer light-emitting devices （PLEDs） are fabricated, with a newly synthesized blue conjugated polymer, poly[（9,9-bis（4-（2-ethylhexyloxy）phenyl）-fluorene）-co-（3,7-dibenziothiene-S,S- dioxide15）] （PPF-3,TSO15）, chosen as host. High luminous efficiencies of 7.4 cd.A-1 and 27.4 cd.A-1 are achieved in red and green PLEDs, respectively, by optimizing the doping concentrations of red phosphorescent dye iridium bis（1- phenylisoquinoline） （acetylacetonate） （Ir（piq）） and green phosphorescent dye iridium tris（2-（4-tolyl）pyridinato-N, C2＇） （Ir（mppy）3）.Furthermore, highly efficient white PLEDs （WPLEDs） with the Commission Internationale de l＇Eclairage （CIE） coordinates of （0.35, 0.38） are successfully produced by carefully controlling the doping concentration of the irid- ium complex. The obtained WPLEDs show maximal efficiencies of 14.4 cd.A-1 and 10.1 lm.W-1, which are comparable to those of incandescent bulbs. Moreover, the electroluminescent spectrum of the white device with an initial luminance of about 1000 cd.m-2 is stable, subject to constant applied current stress, indicating that good device stability can be obtained in this system.
基金Project supported by the National Natural Science Foundation of China(91222110)Key Project of Industry-University-Research of Science and Technology Department of Fujian Province(2010H6029,2012H6026)+1 种基金Key Project of Advanced Industry of Science and Technology Department of Fujian Province(2013H0053)the Training Program of Fujian Excellent Talents in University
文摘The red long-lasting phosphorescent （LLP） of β-Zn3（POa）2：Mn2＋,pr3＋ material was prepared through combustion and conventional solid-state sintering methods. The influence of Pr3＋ ions on luminescence and LLP of Mn2＋ in 13-Zn3（POa）2：Mn2＋,pr3＋ phosphor was systematically investigated. The phosphor presented a strong photoluminescence peak at 620 nm attributed to the 4T1g→ 6A1 g transition of Mn2＋ ions in octahedral coordination. Red LLP was observed in β-Zn3（PO4）2：Mn2＋,Pr3＋ phosphors with persistence time for more than 2 h. It was found that the long persistent phosphorescent performance of Mn2＋ such as brightness and duration was improved by the energy transfer from Pr3＋ to Mn2＋ when Pr3＋ ions as sensitizers were doped into matrix. The fact that the TL peak at low temperature was largely enhanced in Mn2＋, Pr3＋ codoped ^-Zn3（PO4）2 phosphor showed the significant increase of defect concentration with suitable depth. There existed two factors working together to be responsible for the enhancement of LLP performance in β-Zn3（PO4）2：Mn2＋,Pr3＋.
基金Project supported by the National Natural Science Foundation of China(Grant No.61675041)the National Science Funds for Creative Research Groups of China(Grant No.61421002)
文摘Organic optoelectronic integrated devices（OIDs） with ultraviolet（UV） photodetectivity and different color emitting were constructed by using a thermally activated delayed fluorescence（TADF） material 4, 5-bis（carbazol-9-yl）-1, 2-dicyanobenzene（2 CzPN） as host. The OIDs doping with typical red phosphorescent dye [tris（1-phenylisoquinoline）iridium（Ⅲ）, Ir（piq）3], orange phosphorescent dye {bis[2-（4-tertbutylphenyl）benzothiazolato-N,C-（2＇）]iridium（acetylacetonate）,（tbt）2 Ir（acac）}, and blue phosphorescent dye [bis（2, 4-di-fluorophenylpyridinato）-tetrakis（1-pyrazolyl）borate iridium（Ⅲ）, FIr6] were investigated and compared. The（tbt）2 Ir（acac）-doped orange device showed better performance than those of red and blue devices, which was ascribed to more effective energy transfer. Meanwhile, at a low dopant concentration of 3 wt.%, the（tbt）2 Ir（acac）-doped OIDs showed the maximum luminance, current efficiency, power efficiency of 70786 cd/m^2, 39.55 cd/A, and 23.92 lm/W, respectively, and a decent detectivity of 1.07 × 10^11 Jones at a bias of -2 V under the UV-350 nm illumination. This work may arouse widespread interest in constructing high efficiency and luminance OIDs based on doping phosphorescent dye.
基金supported by National Natural Science Foundation of China(No. 61605158)the Science and TechnologyDepartment of Shaanxi Province(No. 2016JQ2028)the Education Department of Shaanxi Province(No. 16JK1790)
文摘2,7-Di（9,9-dimethyl-9H-fluoren-l-yl）-9H-thioxanthen-9-one （DMBFTX） with thermally activated delayed fluorescence （TADF） was well designed and synthesized. The phosphorescent organic lightemitting device （PHOLED） based on this novel TADF host material displays a stable red phosphorescence region, a peak external quantum efficiency （EQE） value of 12.9% and a low EQE roll-off of 38.8%at a luminance of 10000 cd/m2, which is benefited from the reverse intersystem crossing （RISC） of TADF host and less populated triplet exitons. Notably, the red device based on the TADF host DMBFrX exhibits superior electroluminescence performance and reduced efficiency roll-offcompared with the one hosted by commercially available host 1,3-bis（9-carbazolyl）benzene （mCP）, illustrating the high potential of employing the TADF host material with small energy gap to reduce efficiency roll-off in PHOLED.
基金support from the National Natural Science Foundation of China(Nos.22175069,22061018,21702079 and 21772054)the 111 Project(No.B17019),the Natural Science Foundation for Distinguished Young Scholars of Jiangxi Province(No.20212ACB213003)the Academic and Technical Leader Plan of Jiangxi Provincial Main Disciplines(No.20212BCJ23004).
文摘Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work,a series of mononuclear gold(Ⅰ) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(Ⅰ)-containing complexes. In addition, these phosphors display typical aggregation-induced emission(AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.
文摘A series of green phosphorescent organic light-emitting diodes based on bipolar-transporting material 4,4Lbis- （carbazol-9-yl） biphenyl （CBP） are prepared. We insert a mixed host emitting interlayer （CBPx： electron- transporting material 1,3,＆tris （N-phenylbenzimidazole-2yl） （TPBi）1-X） in the middle of the emitting layer, and the best performance appears when x is 2/3. The position of this interlayer can also affect the performanee of phosphorescent organic light-emitting diodes. When this interlayer is close to the side of the electron transporting layer, the maximum value of luminance, the current efficiency and the power efficiency are 34090cd/m2 at 12 V, 60. 6 cd/A and 56.6 lm/W, respectively.
基金supported by the National Natural Science Foundation of China(No.51573036)the Fundamental Research Funds for the Central Universities of China(No.JD2016JGPY0007)the Industry-University-Research Cooperation Project of Aviation Industry Corporation of China(No.CXY2013HFGD20)
文摘We fabricated phosphorescent organic light-emitting diodes(Ph OLEDs) using thermally activated delayed fluorescence(TADF) material 10,10’-(4,4’-sulfonylbis(4,1-phenylene)) bis(9,9-dimethyl-9,10-dihydroacridine)(DMAC-DPS) with low concentration, which showed better performance compared with 1,3-bis(carbazole-9-yl) benzene(m CP) based devices. When the concentration of DMAC-DPS was 1 wt%, the driving voltage of the device was only 3.3 V at 1 000 cd/m2, and the efficiency and lifetime of the device were effectively improved compared with those of m CP based devices. The result indicated that DMAC-DPS could effectively improve the performance of phosphorescent devices. We believe that the better device performance can be attributed to the optimization of the energy transfer process in the emitter layer and lifetime of triplet excitons by DMAC-DPS. The study may provide a simple and effective strategy to achieve high-performance OLEDs.
基金Supported by the Nanjing University of Telecommunication and Posts under Grant No NY212010the National Natural Science Foundation of China under Grant Nos 91233117,50973104 and 51333007+2 种基金the Natural Science Fund of Jiangsu Province under Grant No BK2012834the National Basic Research Program of China under Grant No 2015CB932200the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A high-efficiency green phosphorescent organic light emitting diode with a simplified structure is achieved that is free of a hole transport layer. The design of this kind of device structure not only saves the consumption of organic materials but also greatly reduces the structural heterogeneities and effectively facilitates the charge injection into the emissive layer. The resulting green phosphorescent organic light-emitting diodes （PHOLEDs） exhibit higher electroluminescent efficiency. The maximum external quantum efficiency and current efficiency reach 23.7% and 88 cd/A, respectively. Moreover the device demonstrates satisfactory stability, keeping 23.7% and 88cd/A, 22% and 82cd/A, respectively, at a luminance of 100 and 1000cd/m2. The working mechanism for achieving high efficiency based on such a simple device structure is discussed correspondingly. The improved charge carrier injection and transport balance are proved to prominently contribute to achieve the high efficiency and great stability at high luminance in the green PHOLEDs.
基金financially supported by the Major Research Program from the State Ministry of Science and Technology(No.2012CB933301)the National Natural Science Foundation of China(No.21574068)+3 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.YX03001)Natural Science Foundation of Jiangsu Province(No.BM2012010)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.15KJB150022)Jiangsu Government Scholarship for Overseas Studies
文摘Four novel polymers, poly（3,6-9-decyl-carbazole-alt-1,3-benzene） （PB13CZ）, poly（3,6-9-decyl-carbazole-alt- bis（4-phenyl） （phenyl） phosphine oxide） （PTPPO38CZ）, poly（3,6-9-decyl-carbazole-alt-2,4-phenyl（diphenyl） phosphine oxide） （PTPPO13CZ） and poly（3,6-9-decyl-carbazole-alt-bis（3-phenyl） （phenyl） phosphine oxide） （PTTPO27CZ） were synthesized, and their thermal, photophysical properties and device applications were further investigated to correlate the chemical structures with the photoelectric performance of bipolar host materials for phosphorescent organic light emitting diodes. All of them show high thermal stability as revealed by their high glass transition temperatures and thermal decomposition temperatures at 5% weight loss. These polymers have wide band gaps and relatively high triplet energy levels. As a result, the spin coating method was used to prepare the green phosphorescent organic light emitting diodes with polymers PTPPO38CZ, PTPPO13CZ and PTTPO27CZ as the typical host materials. The green device of polymer PTPPO38CZ as host material shows electroluminescent performance with maximum current efficiency of 2.16 cd.A-1, maximum external quantum efficiency of 0.7%, maximum brightness of 1475 cd.m-2 and reduced efficiency roll-off of 7.14% at 600 cd.m-2, which are much better than those of the same devices hosted by polymers PTTPO27CZ and PTPPO13CZ.
基金supported by the National Natural Science Foundation of China(Nos.20472060 and 21072141)Basic Research Fund of Education Bureau of Sichuan Province,China(No.08ZA040).
文摘A novel phosphorescent cyclometalated platinum dimer with bis-[2-（p-dodecyloxyphenyl） pyridyll-hexane-1,6-diol as ligand and 1,3-（1-n-hexyl,3-n-heptadecyl）diketone as ancillary ligand was synthesized.The chemical structure and liquid crystal property of the dimer were characterized by ~1H NMR,ESl-MS,polarizing optical microscopy（POM） and differential scanning calorimetry （DSC）.The aligned film of title compound on the rubbed polyimide film is intensely emissive at room temperature with emission maximum at 516nm.The luminescence dichroic ratio（（？） ） at 516 nm is 3.1.
基金supported by the Development Foundation for Electronic and Information Industry(2010),the Science and Technology Commission of Shanghai Municipality(Grant No.10DZ1140502)the Mechatronics Engineering Innovation Group Project from Shanghai Education Commissionthe Key Laboratory of Advanced Display and System Applications(Shanghai University),Ministry of Education,China(Grant No.P201004)
文摘Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.
基金Funded by the National Natural Science Foundation of China(No.30871973)
文摘High-efficiency blue electrophosphorescent organic light-emitting devices employing MoO3 used as hole injection layer （HIL） and MoO3 doped N,N-dicarbazoly-3,5-benzene （mCP） as hole transport layer （HTL） were demonstrated. The blue OLED with the novel anode structure and TAPC used as electron blocking layer show a low turn-on voltage of 2.4 V, a maximum power efficiency of 33.6 lm/W at 3.1 V and 25 lrn/W with 1 000 cd/m2 at 3.8 V. It is also found that the efficiency of the devices is dependent on the different EBL materials. This is may because of relationship with the charge mobility and the triplet energy level of EBL materials. The device efficiency is determined by the charge balance which plays an important role.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.60425101）, the Program for the New Century Excellent Talents in University of Ministry of Education of China （No.NCET-06-0812）, and the Young Talent Project of University of Electronic Science and Technology of China （No.060206）.
文摘White organic light-emitting diodes were fabricated by using a novel phosphorescence bis（1,2-diphenyl-1H-benzoimidazole）iridium（acetylacetonate）[（pbi）2Ir（acac）] as sensitizer and a fluorescent dye of 4- （dicyanomethylene）-2-t-butyl-6-（1,1,7,7-tetramethyljulolidyl-9-enyl）-4H-pyran （DCJTB） codoped into a carbazole polymer of poly（N-vinylcarbazole） （PVK）. Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of （pbi）2Ir（acac） and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of （pbi）2Ir（acac） and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the vips enabled a strong yellow emission from （pbi）2Ir（acac） and DCJTB, where （pbi）2Ir（acac） plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N＇-diphenyl-N,N＇-bis（1- naphthyl）（1,1＇-biphenyl）-4,4＇-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1＇Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.
文摘To elucidate the nature of low-lying triplet states and the effect of ligand modifica- tions on the excited-state properties of functional cationic iridium complexes, the solvent- dependent excited-state dynamics of two phosphorescent cationic iridium（Ⅲ） complexes, namely [Ir（dph-oxd）2（bpy）]PF6 （1） and [Ir（dph-oxd）2（pzpy）]Pf6 （2）, were investigated by femtosecond and nanosecond transient absorption spectroscopy. Upon photoexcitation to the metal-to-ligand charge-transfer （MLCT） states, the excited-state dynamics shows a rapid process （τ-=0.7-3 ps） for the formation of solvent stabilized 3MLCT states, which significantly depends on the solvent polarity for both 1 and 2. Sequentially, a relatively slow process assigned to the vibrational cooling/geometrical relaxation and a long-lived phospho- rescent emissive state is identified. Due to the different excited-state electronic structures regulated by ancillary ligands, the solvation-induced stabilization of the 3MLCT state in 1 is faster than that in 2. The present results provide a better sight of excited-state relaxation dynamics of ligand-related iridium（Ⅲ） complexes and solvation effects on triplet manifolds.
基金the financial support from the Instrument Developing Project of the Chinese Academy of Sciences (No. YJKYYQ20170009)the National Natural Science Foundation of China(NSFC Nos. 21722603 and 21871083)the Innovation Program of Shanghai Municipal Education Commission
文摘Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.
基金the financial support from the National Natural Science Foundation of China(No.21801052)Hainan University start-up fund(No.KYQD(ZR)1852)the construction program of research platform in Hainan University(No.ZY2019HN09)。
文摘Room temperature phosphorescent(RTP)materials have a variety of applications ranging from bioimaging,optoelectronic devices to information security protection.However,the preparation procedures for these materials are always tedious and time-consuming.Here,we report a micro-wave approach to prepare RTP carbon dots(CDs)in only 8 min.The micro-wave promoted the carbon and boron bond formation using natural compounds glucose and boric acids.This result has been confirmed using TEM,FTIR,XPS and XRD measurements.The C-B hetero atomized material presented a long afterglow property.With the irradiation with UV light,we observed an eight-second RTP by naked eyes after the lamp was turned off,and the phosphorescence lifetime was 487 ms.This excellent performance was mainly due to the formation of B-C bonds that promoted the intersystem crossings(ISC)and non-radiation transition of triplet states.Moreover,the glass state of the materials also helped to stabilize the triplet states of B-CDs and made its non-irradiation inactivated,which resulted in the characteristics of yellow green RTP.These results have demonstrated that micro-wave is a convenient and effective strategy to make hetero atomized RTP material,providing new possibilities for their industrial productions.
