To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)...To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)and a 1,5‑cyclooctadiene(cod)molecule:[Ir(cod)(κ^(3)‑CN^(im)P)]Cl(1⁃Cl),[Ir(cod)(κ^(3)‑CN^(im)P)]PF6(1⁃PF_(6)),and[Ir(cod)(κ^(3)‑CNHP)]Cl(2).The^(1)H NMR spectra,^(31)P NMR spectra,and high‑resolution mass spectra verify the successful synthesis of these three Ir(Ⅰ)‑CNP complexes.Furthermore,single‑crystal X‑ray diffraction analysis confirms the coordination geometry of 1⁃PF_(6).The strong Ir—C(NHC)bond suggests that the carbene carbon plays an enhanced anchoring role to iridium due to its strongσ‑donating ability,which helps stabilize the active metal species during CO_(2)hydrogenation.As a result,the Ir(Ⅰ)‑CNP complex exhibits remarkable activity and long catalytic lifetime for the hydrogenation of CO_(2)to formate,reaching a turnover number(TON)of 1.16×10^(6)after 150 h at a high temperature of 170℃,which was a relatively high value among all the Ir complexes.CCDC:2384071,1⁃PF_(6).展开更多
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
Green-emitting iridium(Ⅲ)complexes were synthesised using chlorobridged dimer(ppy)_(2)Ir_(2)Cl_(2)(ppy)_(2),3-hydroxy-2-methyl-γ-pyranone,2-ethyl-3-hydroxy-4-pyranone,and 5-hydroxy-2-(hydroxymethyl)-1,4-pyranone as ...Green-emitting iridium(Ⅲ)complexes were synthesised using chlorobridged dimer(ppy)_(2)Ir_(2)Cl_(2)(ppy)_(2),3-hydroxy-2-methyl-γ-pyranone,2-ethyl-3-hydroxy-4-pyranone,and 5-hydroxy-2-(hydroxymethyl)-1,4-pyranone as the auxiliary ligand.The structure of the target product was characterised by nuclear magnetic resonance spectroscopy(~1H-NMR),infrared spectroscopy(IR)and mass spectrometry(MS),and its thermal stability,photophysical properties and electrochemical properties were investigated.The results show that the decomposition temperatures of Ir1,Ir2 and Ir3 are 349,292 and 200℃,respectively.The maximum emission wavelength of Ir1,Ir2 and Ir3 dissolved in dichloromethane is 491 nm.The HOMO energy level of Ir1,Ir2 and Ir3 are 5.39,-5.38,and-5.30 eV.The LUMO energy levels are-2.86,-2.85,and-2.80 eV,respectively.展开更多
Three new cyclometalated iridium（m） complexes based on ligands of diphenylquinoline with fluorinated subsfituents were prepared, and characterized by elemental analysis （EA）, ^1H NMR, and mass spectroscopy （MS）....Three new cyclometalated iridium（m） complexes based on ligands of diphenylquinoline with fluorinated subsfituents were prepared, and characterized by elemental analysis （EA）, ^1H NMR, and mass spectroscopy （MS）. The photophysical and electrophosphorescent properties of the complexes were briefly discussed.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
Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylph...Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylphenyl）isoquinoline,bipy = 2,2＇-bipyridine）,have been synthesized and fully characterized.Single crystal X-ray diffraction study has been undertaken on complexes 3a and 3b,which show that each adopts the distorted octahedral coordination geometry with the cis-C,C＇ and trans-N,N＇ configuration.The photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm,respectively.The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a-3b have been calculated with density functional theory（DFT） and time-dependent DFT（TD-DFT）.The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a,as a consequence of the nature of the methyl group.展开更多
Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborate...Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborately designed and synthesized a pair of mononuclear iridium(Ⅲ) complexes with similar structures but different degrees of cationization. [Ir2-f][2PF_(6)] with two counterions is obtained by simple Nmethylation of the ancillary ligand of [Ir1-f][PF_(6)] which is a classic cationic iridium(Ⅲ) complex. Such a tiny modification results in tremendously different optical properties in dilute solutions and powders.[Ir1-f][PF_(6)] exhibits weak light in solution but enhanced emission in solid-state as well as poly(methyl methacrylate) matrix, indicative of its aggregation-induced emission(AIE) activity. On the sharp contrary, [Ir2-f][2PF_(6)] is an aggregation-caused quenching(ACQ) emitter showing strong emission in the isolated state but nearly nonemissive in aggregation states. Benefiting from the appealing characteristics of mechanochromic luminescence and AIE behavior, [Ir1-f][PF_(6)] has been successfully applied in reversible re-writable data recording and cell imaging. These results might provide deep insights into AIE and ACQ phenomenon of iridium(Ⅲ) complexes and facilitate the development of phosphorescent materials with promising properties.展开更多
Two new iridium complexes with C^N=N type ligand(i.e.,Ir(BFPPya)3{tris[3,6-bis(4-fluorophenyl)pyridazine]iridium(III)}and Ir(BDFPPya)3{tris[3,6-bis(2,4-di-fluorophenyl)pyridazine]iridium(III)})attaching with fluorine ...Two new iridium complexes with C^N=N type ligand(i.e.,Ir(BFPPya)3{tris[3,6-bis(4-fluorophenyl)pyridazine]iridium(III)}and Ir(BDFPPya)3{tris[3,6-bis(2,4-di-fluorophenyl)pyridazine]iridium(III)})attaching with fluorine atoms,were synthesized and the effects of fluorination on the material properties and device performance were investigated.Compared with our previously reported fluorine-free analogue material,that is Ir(BPPya)3{tris[3,6-bis(phenyl)pyridazine]iridium(III)},blue shifts in the emission spectra as well as in the long wavelength region of the absorptions were observed.The photoluminescence quantum yield(PLQY)(0.44 and 0.84 vs.0.29),phosphoresces lifetime(0.88 and 1.31 vs.0.66 gs),and oxidation potential(1.10 and 1.37 vs.0.95 V)increased obviously after fluorinating the ligand.In contrast,the thermal stability of the iridium complexes decreased slightly(Td:435 and 402 vs.440℃).In the density functional theory(DFT)calculations,by comparing the steric shape of the three ligands within one optimized molecule,orientational differences among the complexes were observed.In OLED device studies,bluish green electroluminescence with peak emission of 500 nm,using the electron-transporting host of TPBI[2,2',2"-(1,3,5-benzenetriyl)tris(1-phenyl-lH-benzimidazole)]and the most fluorinated dopant of Ir(BDFPPya)3,was achieved with maximum efficiency of 20.3 cd/A.On one hand this efficiency is not satisfactory considering a high PLQY of 0.84.On the other hand with the similar device structure,that the(HOMO-LUMO)s of all the dopants are wrapped within that of the host TPBI,and all the triplet energies of the dopants are smaller than that of the host TPBI,it is abnormal that the ordering of device efficiencies is contradictory to that of PLQY.Assisting with the phosphorescent spectrum of TPBI and the absorption spectra of the dopant,the contradiction was interpreted reasonably.展开更多
Iridium（Ⅲ） complexes are one of the most important electrophosphorescent dyes with tunable emissions in the range of visible and near infrared lights,high photoluminescence yields and short lifetimes for high-effic...Iridium（Ⅲ） complexes are one of the most important electrophosphorescent dyes with tunable emissions in the range of visible and near infrared lights,high photoluminescence yields and short lifetimes for high-efficiency organic light-emitting diodes（OLED） with 100% exciton harvesting.This review summarizes the recent development of electroluminescent Ir^（3＋） complexes functionalized with host-featured carrier-transporting groups,with emphasis on correlations between functionalization,optoelectronic properties and device performance.According to the introducing approaches,the complexes were sorted with conjugated and aliphatic linkages,as well as the types of functional groups.The modification effect on physical properties and the state-of-the-art device performances were discussed.展开更多
A new cyclometalated iridium（IlI） complex Ir（DPP）3 （DPP=2,3-diphenylpyrazine） was prepared by reaction of DPP with iridium trichloride hydrate under microwave irradiation. The structure of the complex was confir...A new cyclometalated iridium（IlI） complex Ir（DPP）3 （DPP=2,3-diphenylpyrazine） was prepared by reaction of DPP with iridium trichloride hydrate under microwave irradiation. The structure of the complex was confirmed by elemental analysis, ^1H NMR, and mass spectroscopy. The UV-Vis absorption and photoluminescent properties of the complex were investigated. The complex shows strong ^1MLCT （singlet metal to ligand charge-transfer） and aMLCT （triplet metal to ligand charge-transfer） absorption at 382 and 504 nm, respectively. The complex also shows strong photoluminescence at 573 nm at room temperature. These results suggest the complex to be a promising phosphorescent material.展开更多
A new cyclometalated iridium(III) complex with the formula [Ir(DPQ)2(acac)] (DPQ= 2,3-diphenylquinoxaline; acac=acetylacetone) was prepared. The structure of the complex was confirmed by Elemental Analysis (EA), 1H NM...A new cyclometalated iridium(III) complex with the formula [Ir(DPQ)2(acac)] (DPQ= 2,3-diphenylquinoxaline; acac=acetylacetone) was prepared. The structure of the complex was confirmed by Elemental Analysis (EA), 1H NMR, and mass spectroscopy (MS). The UV-vis absorption and photoluminescent properties of the complex were investigated.展开更多
Nonlinear optical materials are one of the key research objects in the field of optics, which mainly research the nonlinear effects of the interaction between luminesce and matter. Compared with inorganic nonlinear op...Nonlinear optical materials are one of the key research objects in the field of optics, which mainly research the nonlinear effects of the interaction between luminesce and matter. Compared with inorganic nonlinear optical materials, organic nonlinear materials have outstanding advantages: strong adaptability, high flexibility, low cost, easy modification and damage resistance. In this review, the electric field induced second harmonic generation (EFISH) experimental technology is used to measure and research the nonlinearity of iridium metal complexes. And because of its structural diversity, people can design molecules according to their needs to get the best nonlinear optical response. Organic molecules with large nonlinear coefficients should have the following characteristics: asymmetric charge distribution, the delocalized nature of π electrons, and easy polarization by external electric fields, and a large π conjugated system. In recent years, metal organic compounds have become a leader in the field of optics, mainly because of their very good nonlinear optical properties. In the future, people will do more investigation on the nonlinearity of metal organic complexes. Researchers have shown great interest in iridium metal organic complexes due in particular to their attractive stability and nonlinear activity. This review mainly studies the nonlinear principle, performance test and Measurement of nonlinearity of iridium metal complexes. The nonlinear properties of other metal-metal organic complexes will not be discussed.展开更多
A novel cyclometalated iridium complex with 1, 3, 4-oxadiazole moiety was synthesizedand characterized. Its UV and photoluminescent properties were studied. The strong UVabsorption intensity around 462 nm attributed t...A novel cyclometalated iridium complex with 1, 3, 4-oxadiazole moiety was synthesizedand characterized. Its UV and photoluminescent properties were studied. The strong UVabsorption intensity around 462 nm attributed to spin-forbidden triplet metal–ligand charge transferband and photoluminescence at 518 nm were observed. This indicated that achieved iridiumcomplex could be used as an efficient electrophosphorescent material.展开更多
An iridium （Ⅲ） bis[（4,6-difluorophenyl）pyridinato-N, C^2][6-（6＇-（4＂-（ 5＂-phenyl- 1＂, 3＂, 4＂-oxadiazole-2＂-yl） phenoxy） hexyloxy picolinate） was synthesized and characterized by IH NMR and elementary ...An iridium （Ⅲ） bis[（4,6-difluorophenyl）pyridinato-N, C^2][6-（6＇-（4＂-（ 5＂-phenyl- 1＂, 3＂, 4＂-oxadiazole-2＂-yl） phenoxy） hexyloxy picolinate） was synthesized and characterized by IH NMR and elementary analysis in order to study the effect of ancillary ligand of the oxadiazole-based picolinic acid derivative on optophysical properties of its iridium complex, and further to obtain an iridium complex with highly-efficient blue emission. The thermal stability, UV absorption and photoluminescent properties of this iridium complex were investigated. Compared with iridium （Ⅲ） bis[（4,6-difluorophenyl）pyridinato-N, C^2]（picolinate） reported as a highly-efficient blue electroluminescent material, this iridium complex bearing an oxadiazole-based picolinic acid derivative presents higher thermal stability, more intense UV absorption at 291 nm and similar photoluminescent spectrum peaked at 469 nm. This indicates that tuning ancillary ligand of picolinic acid with an oxadiazole unit can improve the optophysical properties of its iridium complex.展开更多
The solid-state ECL behavior of a water-insoluble bis-cyclometalated （pq）2Ir（N-phMA） complex is presented, in which pq is a 2-phenylquinoline anion and N-phMA is N-phenyl methacrylamide, a monoanionic bidentate li...The solid-state ECL behavior of a water-insoluble bis-cyclometalated （pq）2Ir（N-phMA） complex is presented, in which pq is a 2-phenylquinoline anion and N-phMA is N-phenyl methacrylamide, a monoanionic bidentate ligand. The MWNTs/（pq）2Ir（N-phMA） film, MWNTs/Ru（bpy）3^2＋ film and （pq）2Ir（N-phMA） directly modified glassy carbon electrode were fabricated; only the MWNTs/（pq）2Ir（N-phMA） film can produce steady ECL in the presence of tri-n-propylamine as a coreactant.展开更多
We present a new cyclometalated Ir(III)complexes IrBDP,which could self-assemble into organic nanoparticles(IrBDP NPs).IrBDP NPs show enhanced photodynamic effect and can be engulfed by HeLa cells for cell imaging as ...We present a new cyclometalated Ir(III)complexes IrBDP,which could self-assemble into organic nanoparticles(IrBDP NPs).IrBDP NPs show enhanced photodynamic effect and can be engulfed by HeLa cells for cell imaging as well as photodynamic therapy(PDT)upon low energy irradiation.展开更多
An ionic iridium（Ⅲ） complex[Ir（F2dpyb）（bzdpp）2Cl][OTf]with 1,3-difluoro-4,6-di（2-pyridinyl） benzene（F2dpybH） terdentate ligand and benzyldiphenylphosphine（bzdpp）ligand was synthesized and characterized.Th...An ionic iridium（Ⅲ） complex[Ir（F2dpyb）（bzdpp）2Cl][OTf]with 1,3-difluoro-4,6-di（2-pyridinyl） benzene（F2dpybH） terdentate ligand and benzyldiphenylphosphine（bzdpp）ligand was synthesized and characterized.The structure of iridium complex was verified by single-crystal X-ray crystallography.It crystallizes in monoclinic,space group P21/n with a =14.3654（7）,b = 23.0026（10）,c = 15.7964（7） A°,β = 97.6029（11）,V= 5173.9（4） A°3,Z = 4,F（000） =2552,Dc = 1.645 Mg/m^3,Mr = 1281.49 and μ = 0.071 mm^-1.The UV-vis absorption and phosphorescence of the complex were discussed.The complex was ＇aggregation induced emission（AIE）＇ active.It exhibited no emission in CH2Cl2 solution but strong blue-green emission in solid state under ultraviolet light excitation.The complex emitted a strong phosphorescence centered at493 nm when doped in PMMA.Its lifetime is 0.755 μs and quantum yield is approximately 0.134.展开更多
Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance.But,low in-depth tissue penetration of light limits their effectivity for deeply buried tumors.Encouraged by t...Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance.But,low in-depth tissue penetration of light limits their effectivity for deeply buried tumors.Encouraged by the sonosensitizing ability of the traditional organic photosensitizers,here,we developed AuNPs@Ir1 as a sonosensitizer by hybridizing an organometallic Ir(Ⅲ) complex(Ir1) with ultrasmall gold nanoparticles(AuNPs) for efficient tumor sonodynamic therapy(SDT) for the first time.AuNPs@Ir1 rapidly entered the cancer cells,produced ^(1)O_(2),and catalytically oxidized NADH to NAD;under ultrasound(US)irradiation,thus resulted in cancer cells oncosis.Because of efficient passive retention in tumors post intravenous injection,AuNPs@Ir1 further efficiently inhibited the growth of tumors in-vivo under US stimulation without long-term toxicity to other organs.Overall,this work presents the excellent US triggered in-vitro and in-vivo anticancer profile of the novel AuNPs@Ir1.It is expected to increase the scope of SDT for metal-based anticancer drugs.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
Stimuli-triggered release and alleviating resistance of iridium(Ⅲ)-based drugs at tumor sites remains challengeable for clinical hepatoma therapy.Herein,a doxorubicin@iridium-transferrin(DOX@Ir-TF)nanovesicle was syn...Stimuli-triggered release and alleviating resistance of iridium(Ⅲ)-based drugs at tumor sites remains challengeable for clinical hepatoma therapy.Herein,a doxorubicin@iridium-transferrin(DOX@Ir-TF)nanovesicle was synthesized by carboxylated-transferrin(TF)and doxorubicin-loaded amphiphilic iridium-amino with quaternary ammonium(QA)groups and disulfide bonds.The QA groups enhanced photophysical properties and broadened production capacity of photoinduced-reactive oxygen species(ROS),while the disulfide-bridged bonds regulated oxidative stress levels through reacting with glutathione(GSH);simultaneously,modification of TF improved recognition and endocytosis of the nanovesicle for tumor cells.Based on in-vitro results,a controlled-release behavior of DOX upon a dualresponsiveness of GSH and near-infrared ray(NIR)irradiation was presented,along with high-efficiency generation of ROS.After an intravenous injection,the nanovesicle was targeted at tumor sites,realizing TF-navigated photoacoustic imaging guidance and synergistic chemotherapy-photodynamic therapy under NIR/GSH stimulations.Overall,newly-synthesized DOX@Ir-TF nanovesicle provided a potential in subcutaneous hepatocellular carcinoma therapy due to integrations of targeting delivery,dual-stimuli responsive release,synergistic therapy strategy,and real-time monitoring.展开更多
文摘To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)and a 1,5‑cyclooctadiene(cod)molecule:[Ir(cod)(κ^(3)‑CN^(im)P)]Cl(1⁃Cl),[Ir(cod)(κ^(3)‑CN^(im)P)]PF6(1⁃PF_(6)),and[Ir(cod)(κ^(3)‑CNHP)]Cl(2).The^(1)H NMR spectra,^(31)P NMR spectra,and high‑resolution mass spectra verify the successful synthesis of these three Ir(Ⅰ)‑CNP complexes.Furthermore,single‑crystal X‑ray diffraction analysis confirms the coordination geometry of 1⁃PF_(6).The strong Ir—C(NHC)bond suggests that the carbene carbon plays an enhanced anchoring role to iridium due to its strongσ‑donating ability,which helps stabilize the active metal species during CO_(2)hydrogenation.As a result,the Ir(Ⅰ)‑CNP complex exhibits remarkable activity and long catalytic lifetime for the hydrogenation of CO_(2)to formate,reaching a turnover number(TON)of 1.16×10^(6)after 150 h at a high temperature of 170℃,which was a relatively high value among all the Ir complexes.CCDC:2384071,1⁃PF_(6).
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.
文摘Green-emitting iridium(Ⅲ)complexes were synthesised using chlorobridged dimer(ppy)_(2)Ir_(2)Cl_(2)(ppy)_(2),3-hydroxy-2-methyl-γ-pyranone,2-ethyl-3-hydroxy-4-pyranone,and 5-hydroxy-2-(hydroxymethyl)-1,4-pyranone as the auxiliary ligand.The structure of the target product was characterised by nuclear magnetic resonance spectroscopy(~1H-NMR),infrared spectroscopy(IR)and mass spectrometry(MS),and its thermal stability,photophysical properties and electrochemical properties were investigated.The results show that the decomposition temperatures of Ir1,Ir2 and Ir3 are 349,292 and 200℃,respectively.The maximum emission wavelength of Ir1,Ir2 and Ir3 dissolved in dichloromethane is 491 nm.The HOMO energy level of Ir1,Ir2 and Ir3 are 5.39,-5.38,and-5.30 eV.The LUMO energy levels are-2.86,-2.85,and-2.80 eV,respectively.
基金supported by the National Natural Science Foundation of China(No.20371036 and 20474047)the Program for New Century Excellent Talents in University,the Ministry of Education of Chinathe Hubei Province Science Fund for Distinguished Young Scholar(No.2003ABB008).
文摘Three new cyclometalated iridium（m） complexes based on ligands of diphenylquinoline with fluorinated subsfituents were prepared, and characterized by elemental analysis （EA）, ^1H NMR, and mass spectroscopy （MS）. The photophysical and electrophosphorescent properties of the complexes were briefly discussed.
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supported by the National Natural Science Foundation of China(No.21501037)the Natural Science Foundation of Hainan Province(No.20152017)the Science and Research Project of Education Department of Hainan Province(Nos.Hjkj2013-25 and Hnky2015-27)
文摘Two new fluorinated phenylisoquinoline-based iridium（Ⅲ） complexes,[Ir（f2piq）2（bipy）][PF6]（3a） and[Ir（fmpiq）2（bipy）][PF6]（3b）（f2piq = l-（2,4-difluorophenyl）isoquinoline,fmpiq = 1-（4-fluoro-2-methylphenyl）isoquinoline,bipy = 2,2＇-bipyridine）,have been synthesized and fully characterized.Single crystal X-ray diffraction study has been undertaken on complexes 3a and 3b,which show that each adopts the distorted octahedral coordination geometry with the cis-C,C＇ and trans-N,N＇ configuration.The photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm,respectively.The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a-3b have been calculated with density functional theory（DFT） and time-dependent DFT（TD-DFT）.The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a,as a consequence of the nature of the methyl group.
基金financial support from the National Natural Science Foundation of China(Nos.22175033 and 51902124).
文摘Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborately designed and synthesized a pair of mononuclear iridium(Ⅲ) complexes with similar structures but different degrees of cationization. [Ir2-f][2PF_(6)] with two counterions is obtained by simple Nmethylation of the ancillary ligand of [Ir1-f][PF_(6)] which is a classic cationic iridium(Ⅲ) complex. Such a tiny modification results in tremendously different optical properties in dilute solutions and powders.[Ir1-f][PF_(6)] exhibits weak light in solution but enhanced emission in solid-state as well as poly(methyl methacrylate) matrix, indicative of its aggregation-induced emission(AIE) activity. On the sharp contrary, [Ir2-f][2PF_(6)] is an aggregation-caused quenching(ACQ) emitter showing strong emission in the isolated state but nearly nonemissive in aggregation states. Benefiting from the appealing characteristics of mechanochromic luminescence and AIE behavior, [Ir1-f][PF_(6)] has been successfully applied in reversible re-writable data recording and cell imaging. These results might provide deep insights into AIE and ACQ phenomenon of iridium(Ⅲ) complexes and facilitate the development of phosphorescent materials with promising properties.
基金financially supported by the National Natural Science Foundation of China(61077021,61076016)the Nanjing University of Posts and Telecommunications(NY212076,NY212050)
文摘Two new iridium complexes with C^N=N type ligand(i.e.,Ir(BFPPya)3{tris[3,6-bis(4-fluorophenyl)pyridazine]iridium(III)}and Ir(BDFPPya)3{tris[3,6-bis(2,4-di-fluorophenyl)pyridazine]iridium(III)})attaching with fluorine atoms,were synthesized and the effects of fluorination on the material properties and device performance were investigated.Compared with our previously reported fluorine-free analogue material,that is Ir(BPPya)3{tris[3,6-bis(phenyl)pyridazine]iridium(III)},blue shifts in the emission spectra as well as in the long wavelength region of the absorptions were observed.The photoluminescence quantum yield(PLQY)(0.44 and 0.84 vs.0.29),phosphoresces lifetime(0.88 and 1.31 vs.0.66 gs),and oxidation potential(1.10 and 1.37 vs.0.95 V)increased obviously after fluorinating the ligand.In contrast,the thermal stability of the iridium complexes decreased slightly(Td:435 and 402 vs.440℃).In the density functional theory(DFT)calculations,by comparing the steric shape of the three ligands within one optimized molecule,orientational differences among the complexes were observed.In OLED device studies,bluish green electroluminescence with peak emission of 500 nm,using the electron-transporting host of TPBI[2,2',2"-(1,3,5-benzenetriyl)tris(1-phenyl-lH-benzimidazole)]and the most fluorinated dopant of Ir(BDFPPya)3,was achieved with maximum efficiency of 20.3 cd/A.On one hand this efficiency is not satisfactory considering a high PLQY of 0.84.On the other hand with the similar device structure,that the(HOMO-LUMO)s of all the dopants are wrapped within that of the host TPBI,and all the triplet energies of the dopants are smaller than that of the host TPBI,it is abnormal that the ordering of device efficiencies is contradictory to that of PLQY.Assisting with the phosphorescent spectrum of TPBI and the absorption spectra of the dopant,the contradiction was interpreted reasonably.
基金financially supported by NSFC(Nos.51373050 and 61176020)New Century Excellent Talents Supporting Program of MOE(No.NCET-12-0706)+2 种基金Science and Technology Bureau of Heilongjiang Province(Nos.ZD201402 and JC2015002)Education Bureau of Heilongjiang Province(No.2014CJHB005)the Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China(No.141012)
文摘Iridium（Ⅲ） complexes are one of the most important electrophosphorescent dyes with tunable emissions in the range of visible and near infrared lights,high photoluminescence yields and short lifetimes for high-efficiency organic light-emitting diodes（OLED） with 100% exciton harvesting.This review summarizes the recent development of electroluminescent Ir^（3＋） complexes functionalized with host-featured carrier-transporting groups,with emphasis on correlations between functionalization,optoelectronic properties and device performance.According to the introducing approaches,the complexes were sorted with conjugated and aliphatic linkages,as well as the types of functional groups.The modification effect on physical properties and the state-of-the-art device performances were discussed.
文摘A new cyclometalated iridium（IlI） complex Ir（DPP）3 （DPP=2,3-diphenylpyrazine） was prepared by reaction of DPP with iridium trichloride hydrate under microwave irradiation. The structure of the complex was confirmed by elemental analysis, ^1H NMR, and mass spectroscopy. The UV-Vis absorption and photoluminescent properties of the complex were investigated. The complex shows strong ^1MLCT （singlet metal to ligand charge-transfer） and aMLCT （triplet metal to ligand charge-transfer） absorption at 382 and 504 nm, respectively. The complex also shows strong photoluminescence at 573 nm at room temperature. These results suggest the complex to be a promising phosphorescent material.
文摘A new cyclometalated iridium(III) complex with the formula [Ir(DPQ)2(acac)] (DPQ= 2,3-diphenylquinoxaline; acac=acetylacetone) was prepared. The structure of the complex was confirmed by Elemental Analysis (EA), 1H NMR, and mass spectroscopy (MS). The UV-vis absorption and photoluminescent properties of the complex were investigated.
文摘Nonlinear optical materials are one of the key research objects in the field of optics, which mainly research the nonlinear effects of the interaction between luminesce and matter. Compared with inorganic nonlinear optical materials, organic nonlinear materials have outstanding advantages: strong adaptability, high flexibility, low cost, easy modification and damage resistance. In this review, the electric field induced second harmonic generation (EFISH) experimental technology is used to measure and research the nonlinearity of iridium metal complexes. And because of its structural diversity, people can design molecules according to their needs to get the best nonlinear optical response. Organic molecules with large nonlinear coefficients should have the following characteristics: asymmetric charge distribution, the delocalized nature of π electrons, and easy polarization by external electric fields, and a large π conjugated system. In recent years, metal organic compounds have become a leader in the field of optics, mainly because of their very good nonlinear optical properties. In the future, people will do more investigation on the nonlinearity of metal organic complexes. Researchers have shown great interest in iridium metal organic complexes due in particular to their attractive stability and nonlinear activity. This review mainly studies the nonlinear principle, performance test and Measurement of nonlinearity of iridium metal complexes. The nonlinear properties of other metal-metal organic complexes will not be discussed.
基金This work was supported by the National Natural Science Foundation of China(No.20272014)the Project of National Education Ministry(Project No.204097)National 973 Project of China(Project No.2002CB613400-5).
文摘A novel cyclometalated iridium complex with 1, 3, 4-oxadiazole moiety was synthesizedand characterized. Its UV and photoluminescent properties were studied. The strong UVabsorption intensity around 462 nm attributed to spin-forbidden triplet metal–ligand charge transferband and photoluminescence at 518 nm were observed. This indicated that achieved iridiumcomplex could be used as an efficient electrophosphorescent material.
基金Projects(20772101,50473046) supported by the National Natural Science Foundation of ChinaProject(2007FJ3017) supported by the Hunan Provincial Science Foundation, ChinaProject(07C764) supported by the Science Foundation of the Education Department of Hunan Province,China
文摘An iridium （Ⅲ） bis[（4,6-difluorophenyl）pyridinato-N, C^2][6-（6＇-（4＂-（ 5＂-phenyl- 1＂, 3＂, 4＂-oxadiazole-2＂-yl） phenoxy） hexyloxy picolinate） was synthesized and characterized by IH NMR and elementary analysis in order to study the effect of ancillary ligand of the oxadiazole-based picolinic acid derivative on optophysical properties of its iridium complex, and further to obtain an iridium complex with highly-efficient blue emission. The thermal stability, UV absorption and photoluminescent properties of this iridium complex were investigated. Compared with iridium （Ⅲ） bis[（4,6-difluorophenyl）pyridinato-N, C^2]（picolinate） reported as a highly-efficient blue electroluminescent material, this iridium complex bearing an oxadiazole-based picolinic acid derivative presents higher thermal stability, more intense UV absorption at 291 nm and similar photoluminescent spectrum peaked at 469 nm. This indicates that tuning ancillary ligand of picolinic acid with an oxadiazole unit can improve the optophysical properties of its iridium complex.
基金supported by the National Natural Science Foundation of China (No.20571033).
文摘The solid-state ECL behavior of a water-insoluble bis-cyclometalated （pq）2Ir（N-phMA） complex is presented, in which pq is a 2-phenylquinoline anion and N-phMA is N-phenyl methacrylamide, a monoanionic bidentate ligand. The MWNTs/（pq）2Ir（N-phMA） film, MWNTs/Ru（bpy）3^2＋ film and （pq）2Ir（N-phMA） directly modified glassy carbon electrode were fabricated; only the MWNTs/（pq）2Ir（N-phMA） film can produce steady ECL in the presence of tri-n-propylamine as a coreactant.
基金financially supported by the National Natural Science Foundation of China(Nos.21474012 and 21504089)
文摘We present a new cyclometalated Ir(III)complexes IrBDP,which could self-assemble into organic nanoparticles(IrBDP NPs).IrBDP NPs show enhanced photodynamic effect and can be engulfed by HeLa cells for cell imaging as well as photodynamic therapy(PDT)upon low energy irradiation.
基金Supported by the National Natural Science Foundation of China(21572001)the Natural Science Foundation from Bureau of Education of Anhui Province(KJ2013A063)the Anhui Province Undergraduate Innovation and Entrepreneurship Training Program(201510360119)
文摘An ionic iridium（Ⅲ） complex[Ir（F2dpyb）（bzdpp）2Cl][OTf]with 1,3-difluoro-4,6-di（2-pyridinyl） benzene（F2dpybH） terdentate ligand and benzyldiphenylphosphine（bzdpp）ligand was synthesized and characterized.The structure of iridium complex was verified by single-crystal X-ray crystallography.It crystallizes in monoclinic,space group P21/n with a =14.3654（7）,b = 23.0026（10）,c = 15.7964（7） A°,β = 97.6029（11）,V= 5173.9（4） A°3,Z = 4,F（000） =2552,Dc = 1.645 Mg/m^3,Mr = 1281.49 and μ = 0.071 mm^-1.The UV-vis absorption and phosphorescence of the complex were discussed.The complex was ＇aggregation induced emission（AIE）＇ active.It exhibited no emission in CH2Cl2 solution but strong blue-green emission in solid state under ultraviolet light excitation.The complex emitted a strong phosphorescence centered at493 nm when doped in PMMA.Its lifetime is 0.755 μs and quantum yield is approximately 0.134.
基金financial support of the National Natural Science Foundation of China (NSFC, Nos. 22077085, 22007104)the Project of the Natural Science Foundation of Guangdong Province(No. 2019A1515011958)+2 种基金the Science and Technology Foundation of Shenzhen (No. JCYJ20190808153209537)DST,the Government of India (No. DST/INSPIRE/04/2019/000492)the Instrumental Analysis Center of Shenzhen University。
文摘Metal-based compounds with excellent photo-physical properties show good photochemotherapeutic performance.But,low in-depth tissue penetration of light limits their effectivity for deeply buried tumors.Encouraged by the sonosensitizing ability of the traditional organic photosensitizers,here,we developed AuNPs@Ir1 as a sonosensitizer by hybridizing an organometallic Ir(Ⅲ) complex(Ir1) with ultrasmall gold nanoparticles(AuNPs) for efficient tumor sonodynamic therapy(SDT) for the first time.AuNPs@Ir1 rapidly entered the cancer cells,produced ^(1)O_(2),and catalytically oxidized NADH to NAD;under ultrasound(US)irradiation,thus resulted in cancer cells oncosis.Because of efficient passive retention in tumors post intravenous injection,AuNPs@Ir1 further efficiently inhibited the growth of tumors in-vivo under US stimulation without long-term toxicity to other organs.Overall,this work presents the excellent US triggered in-vitro and in-vivo anticancer profile of the novel AuNPs@Ir1.It is expected to increase the scope of SDT for metal-based anticancer drugs.
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.
基金supported by the National Key R&D Program of China(Nos.2022YFB3808000,2022YFB3808001)the Project for High-Level Talent Innovation and Entrepreneurship of Quanzhou(No.2022C016R)+1 种基金the Medical Innovation Project of Science and Technology Program of Fujian Provincial Health Commission(No.2021CXA006)the Key Program of Qingyuan Innovation Laboratory(No.00221002).
文摘Stimuli-triggered release and alleviating resistance of iridium(Ⅲ)-based drugs at tumor sites remains challengeable for clinical hepatoma therapy.Herein,a doxorubicin@iridium-transferrin(DOX@Ir-TF)nanovesicle was synthesized by carboxylated-transferrin(TF)and doxorubicin-loaded amphiphilic iridium-amino with quaternary ammonium(QA)groups and disulfide bonds.The QA groups enhanced photophysical properties and broadened production capacity of photoinduced-reactive oxygen species(ROS),while the disulfide-bridged bonds regulated oxidative stress levels through reacting with glutathione(GSH);simultaneously,modification of TF improved recognition and endocytosis of the nanovesicle for tumor cells.Based on in-vitro results,a controlled-release behavior of DOX upon a dualresponsiveness of GSH and near-infrared ray(NIR)irradiation was presented,along with high-efficiency generation of ROS.After an intravenous injection,the nanovesicle was targeted at tumor sites,realizing TF-navigated photoacoustic imaging guidance and synergistic chemotherapy-photodynamic therapy under NIR/GSH stimulations.Overall,newly-synthesized DOX@Ir-TF nanovesicle provided a potential in subcutaneous hepatocellular carcinoma therapy due to integrations of targeting delivery,dual-stimuli responsive release,synergistic therapy strategy,and real-time monitoring.
