Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compou...Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as guest and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs.展开更多
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho...A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.展开更多
Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent ma...Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.展开更多
A new functionalized heteroleptic iridium complex coordinated with 1-phenylisoquinoline （1-piq） and a functionalized fl-diketone （G1）, Ir（1-piq）2G1, was synthesized and characterized by 1H-NMR, mass spectrometry...A new functionalized heteroleptic iridium complex coordinated with 1-phenylisoquinoline （1-piq） and a functionalized fl-diketone （G1）, Ir（1-piq）2G1, was synthesized and characterized by 1H-NMR, mass spectrometry and elemental analysis. The larger conjugation of the replacement of acetylacetone （acac） by a functionalizedβ-diketonate ligand led to a significant decrease in the HOMO level toward vacuum level, while Ir（1-piq）2G1 and Ir（1-piq）2（acac） showed red phosphorescent emissions of about 620 nm in dichloromethane solution. The phosphorescent polymer light-emitting devices were achieved, with the complexes incorporated with polyfluorene （PFO） as a host polymer doped with 30% of 5-（4-biphenylyl）-2-（4-tert-butylphenyl）-1,3,4-oxadiazole （PBD） as electron transport material. The energy transfer mechanism of the devices was also discussed. The lower EL performance of Ir（1-piq）2G1 is ascribed to the inter-ligand energy transfer, indicating that it is important to control the energy level of the cyclometalated and ancillary ligands.展开更多
Theoretically,blue phosphorescent materials are capable of achieving 100%internal quantum effi-ciency.Nevertheless,the mutual constraints among efficiency,color purity,and stability remain one of the key bottlenecks i...Theoretically,blue phosphorescent materials are capable of achieving 100%internal quantum effi-ciency.Nevertheless,the mutual constraints among efficiency,color purity,and stability remain one of the key bottlenecks in the industrialization of organic light-emitting diodes(OLEDs).In addition,the design and application of host materials also exert a significant impact on the overall performance of blue light-emitting de-vices.To address this issue,this study constructs a series of host materials with high triplet energy levels by designing different connection modes,based on 9-phenylcarbazole and benzimidazole units.Through a combi-nation of theoretical and experimental approaches,the correlation between the chemical structure and perfor-mance has been unraveled.It is found that the designed and synthesized blue phosphorescent bipolar host ma-terials based on different biphenyl linking sites,i.e.,9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-bi-phenyl]-3-yl)-9H-carbazole(mCzmBI),9-(2'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-3-yl)-9H-carbazole(mCzoBI)and 9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-2-yl)-9H-carbazole(oCzmBI).The three compounds have a similar triplet energy level of 2.70 eV,accompanied with the glass transition temperatures of 92℃,103℃,and 93℃respectively.mCzmBI,mCzoBI and oCzmBI are regioiso-mers,but differ in the linking sites of carbazole and benzimidazole on the biphenyl linker.This difference in linking positions enables effective regulation of the host materials’properties.Constructed with the blue phos-phorescent material bis(4,6-difluorophenylpyridinato-N,C2)picolinatoiridium(Ⅲ)(FIrpic)as the guest,the influence of the three hosts on device performance is clarified.Overall,the device using mCzmBI,a host linked by biphenyl at double meta-positions,achieved a maximum current efficiency of 24.9 cd·A^(-1)and a max-imum external quantum efficiency exceeding 12.8%,it also demonstrates low efficiency roll-off under highbrightness conditions.This work offers an effective strategy to the development of high-efficiency blue phospho-rescent hosts.展开更多
文摘Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as guest and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs.
文摘A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.
文摘Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.
基金Project(50803008) supported by the National Natural Science Foundation of ChinaProject(2002CB613403) supported by the Ministry of Science and Technology (MOST) of China+1 种基金Project(09JJ6085) supported by the Natural Science Foundation of Hunan Province,ChinaProject(08hjyh02) supported by the Open Project Program of Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education,China
文摘A new functionalized heteroleptic iridium complex coordinated with 1-phenylisoquinoline （1-piq） and a functionalized fl-diketone （G1）, Ir（1-piq）2G1, was synthesized and characterized by 1H-NMR, mass spectrometry and elemental analysis. The larger conjugation of the replacement of acetylacetone （acac） by a functionalizedβ-diketonate ligand led to a significant decrease in the HOMO level toward vacuum level, while Ir（1-piq）2G1 and Ir（1-piq）2（acac） showed red phosphorescent emissions of about 620 nm in dichloromethane solution. The phosphorescent polymer light-emitting devices were achieved, with the complexes incorporated with polyfluorene （PFO） as a host polymer doped with 30% of 5-（4-biphenylyl）-2-（4-tert-butylphenyl）-1,3,4-oxadiazole （PBD） as electron transport material. The energy transfer mechanism of the devices was also discussed. The lower EL performance of Ir（1-piq）2G1 is ascribed to the inter-ligand energy transfer, indicating that it is important to control the energy level of the cyclometalated and ancillary ligands.
文摘Theoretically,blue phosphorescent materials are capable of achieving 100%internal quantum effi-ciency.Nevertheless,the mutual constraints among efficiency,color purity,and stability remain one of the key bottlenecks in the industrialization of organic light-emitting diodes(OLEDs).In addition,the design and application of host materials also exert a significant impact on the overall performance of blue light-emitting de-vices.To address this issue,this study constructs a series of host materials with high triplet energy levels by designing different connection modes,based on 9-phenylcarbazole and benzimidazole units.Through a combi-nation of theoretical and experimental approaches,the correlation between the chemical structure and perfor-mance has been unraveled.It is found that the designed and synthesized blue phosphorescent bipolar host ma-terials based on different biphenyl linking sites,i.e.,9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-bi-phenyl]-3-yl)-9H-carbazole(mCzmBI),9-(2'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-3-yl)-9H-carbazole(mCzoBI)and 9-(3'-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1'-biphenyl]-2-yl)-9H-carbazole(oCzmBI).The three compounds have a similar triplet energy level of 2.70 eV,accompanied with the glass transition temperatures of 92℃,103℃,and 93℃respectively.mCzmBI,mCzoBI and oCzmBI are regioiso-mers,but differ in the linking sites of carbazole and benzimidazole on the biphenyl linker.This difference in linking positions enables effective regulation of the host materials’properties.Constructed with the blue phos-phorescent material bis(4,6-difluorophenylpyridinato-N,C2)picolinatoiridium(Ⅲ)(FIrpic)as the guest,the influence of the three hosts on device performance is clarified.Overall,the device using mCzmBI,a host linked by biphenyl at double meta-positions,achieved a maximum current efficiency of 24.9 cd·A^(-1)and a max-imum external quantum efficiency exceeding 12.8%,it also demonstrates low efficiency roll-off under highbrightness conditions.This work offers an effective strategy to the development of high-efficiency blue phospho-rescent hosts.
