Pengfei Yan

Heilongjiang University, Charbin, Heilongjiang Sheng, China

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Publications (84)337.51 Total impact

  • Bing Li · Hongfeng Li · Peng Chen · Wenbin Sun · Cheng Wang · Ting Gao · Pengfei Yan ·
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    ABSTRACT: A bis-β-diketone, bis(4,4,4-trifluoro-1,3-dioxobutyl)(2,2'-bithienyl) (BTT), which can be looked upon as coupling of two mono-β-diketones (2-thenoyltrifluoroacetone, TTA) at the 5,5'-position of thiophene ring, has been designed for exploring the advantages of binuclear helical structure in sensitizing the lanthanide NIR luminescence. The Yb(iii) ion was selected as the luminescent center, and its corresponding mono-β-diketone complex Yb(TTA)3(DMSO) () and bis-β-diketone complex Yb2(BTT)3(DMSO)4 () were synthesized and isolated. X-ray crystallographical analysis reveals that the bis-β-diketone complex Yb2(BTT)3(DMSO)4 adopts a triple-stranded dinuclear structure, in which the two Yb(iii) ions are helically wrapped by three ligands, and each Yb(iii) ion is eight-coordinated by six oxygen atoms from three ligands and two oxygen atoms from the coordinated DMSO molecules. Whereas, the mono-β-diketone complex Yb(TTA)3(DMSO) is a mononuclear structure, the central Yb(iii) ion is coordinated by seven oxygen atoms from three ligands and a DMSO molecule. The photophysical properties related to the electronic transition are characterized by the absorbance spectra, the emission spectra, the emission quantum yields, the emission lifetimes, and the radiative (kr) and nonradiative rate constants (knr). The luminescence quantum yield experiment reveals that the dinuclear complex has about 10 times luminescence enhancement compared with the mononuclear complex. This enhancement mainly benefits from its helical structure, which effectively depresses the nonradiative transition caused by high-energy oscillators in ligands, and the part-encapsulated structure decreases the probability of solvents entering the metal centers.
    Physical Chemistry Chemical Physics 10/2015; DOI:10.1039/c5cp05888k · 4.49 Impact Factor
  • Peng Chen · Hongfeng Li · Wenbin Sun · Jinkui Tang · Lei Zhang · Pengfei Yan ·
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    ABSTRACT: Helical structures are vital in chemistry and biochemistry and their importance has been reconsidered since the structure of DNA was revealed. Over the past decades, the advantages of the helical structures of bis-β-diketonate-based multiple-stranded Ln3+ complexes have been speculated with respect to their unique structures. Based on our previous study, we have designed a V-shaped bis-β-diketone ligand, H2MBDA, which has been utilized to crystallographically synthesize triple-stranded and quadruple-stranded dinuclear Dy3+ complexes. In contrast to the absence of crystallographical results in previous studies, the successful crystallization in this study has contributed to the functionalization of the -CF3 groups into the ligand as the termini, which have played a key role in the crystallization through intermolecular weak interactions. Both complexes display slow magnetic relaxation. The auxiliary ligand, phenanthroline, contributes to both tuning the structure and strengthening the anisotropy barrier.
    CrystEngComm 08/2015; 17(37). DOI:10.1039/C5CE01067E · 4.03 Impact Factor
  • Qingyan Sun · Pengfei Yan · Wanying Niu · wenyi chu · Xu Yao · Guanghui An · Guangming Li ·
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    ABSTRACT: A series of five β-diketone erbium complexes with various azacyclo-auxiliary ligands, namely, Er(Hbta)3(H2O)2 (1), Er(Hbta)3(bpy) (2), Er(Hbta)3(phen) (3), Er(Hbta)3(dpq) (4) and Er(Hbta)3(dppz) (5) (Hbta = benzoyltrifluoroacetone, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, dpq = pyrazino[2,3-f][1,10]phenanthroline, dppz = dipyrido[3,2-a:2′,3′-c]phenazine) have been isolated and characterized by X-ray crystallographic analysis. Near-infrared luminescence analysis reveals that all complexes 1-5 exhibit strong NIR luminescence of Er(iii) ions around 1535 nm with the highest lifetime of 4.532 μs, quantum yield of 3.24 × 10-4 and broadband emission around 1.5 μm for complex 5, in which the azacyclo-auxiliary ligand absorbs and transfers the energy leading to complete quenching of the ligand-associated visible emission. The energy transfer processes among benzoyltrifluoroacetone, the Er(iii) ion and the auxiliary ligands in complexes 1-5 have been investigated. This journal is
    RSC Advances 07/2015; 5(81). DOI:10.1039/C5RA12954K · 3.84 Impact Factor
  • Rui Jia · Ting Gao · Yu Yang · Wenbin Sun · Ruoxi Chen · Pengfei Yan · Guangfeng Hou ·
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    ABSTRACT: The luminescence properties of the tetranuclear bimetallic lanthanide complexes Sm2Eu2 (1) and Eu2Tb2 (2), were compared with those of the analogous homometallic complexes [Sm4(μ3-OH)2(salen)2(acac)6(CH3OH)2]·CH3OH (3) and [Eu4(μ3-OH)2(salen)2(acac)6(CH3OH)2] (4) [H2salen = N, N′-ethylenebis(salicylideneimine), Hacac = acetylacetonate]. X-ray crystallographic analysis reveals that complexes 3 and 4 have planar tetranuclear structures. For the Eu2Tb2 configurational isomer, the TbIII ion in complex 2 mainly serves as a sensitizer. The quantum yields and lifetime measurements for 2 support the premise that Ln/Ln energy transfer occurs in such lanthanide bimetallic complexes, along with the usual ligand-to-metal triplet energy pathways. Complexes 3 and 4 exhibit the characteristic metal-centered emission.
    Zeitschrift für anorganische Chemie 07/2015; 641(11). DOI:10.1002/zaac.201500138 · 1.16 Impact Factor
  • Yanping Dong · Pengfei Yan · Xiaoyan Zou · Guangming Li ·
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    ABSTRACT: A series of four β-diketone mononuclear dysprosium complexes, namely, Dy(DBM)3(bpy) (1), Dy(DBM)3(phen)·Tol (2), Dy(DBM)3(dpq)·Tol (3), and Dy(DBM)3(dppz) (4) (bpy = 2, 2'-bipyridine, phen = 1, 10-phenanthroline, dpq = dipyrazine [2, 3-f: 2´, 3´-h] quinoxaline, dppz = dipyrido [3, 2-a:2´, 3´-c] phenazine, Tol = toluene) have been isolated by the reactions of Dibenzoylmethane (DBM), azacyclo-auxiliary ligands and DyCl3·6H2O. X-ray crystallographic analysis reveals that complexes 1−4 are all eight-coordinated mononuclear structures. The azacyclo-auxiliary ligands have a dramatic effect on the structure and magnetic characteristics of complexes 1−4, originated from different degrees deviation from ideal coordination symmetry. Complexes 1 and 2 display a single relaxation mode under 0 Oe and complexes 3 and 4 display two single relaxation modes under 2000 Oe.
    06/2015; 2(9). DOI:10.1039/C5QI00079C
  • Peng Chen · Meiqi Zhang · Wenbin Sun · Hongfeng Li · Lang Zhao · Pengfei Yan ·
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    ABSTRACT: Self-assembly of 2-aldehyde-8-hydroxyquinoline, histamine dichloride and LnX3•6H2O (X− = OAc−, NO3− and ClO4−) affords a series of lanthanide complexes Nd3(nma)2(OAc)7∙3CH3OH∙0.5H2O (1a), Ln3(nma)2(OAc)7∙2CH3OH [Ln = Tb (1b) and Dy (1c)], [Ln(nma)(NO3)2(DMSO)]∙CH3OH [Ln = Nd (2a), Tb (2b), Dy (2c) and Er (2d)] and [Dy(nma)2]∙ClO4∙0.5CH3OH (3) (Hnma = N-(2-(8-hydroxylquinolinyl)methane(2-(4-imidazolyl)ethanamine)). It is noted that the formation and structures of 1–3 are anion-dependent, where diverse coordination modes are detected for acetates in trinuclear 1 as compared to single coordination mode for nitrates in mononuclear 2. In the case of 3, the Dy3+ ion is completely encapsulated by two ligands with uncoordinated perchlorate anion balancing the charge. Magnetic measurement shows that the Dy complexes of 1c, 2c and 3 exhibit slow relaxations under zero dc field. It is noted that single molecular magnet behavior is obtained for 2c and 3 under an applied dc field of 2000 Oe.
    CrystEngComm 06/2015; 17(27). DOI:10.1039/C5CE00925A · 4.03 Impact Factor
  • Hongfeng Li · Tianyu Zhu · Peng Chen · Wenbin Sun · Ting Gao · Pengfei Yan ·
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    ABSTRACT: Two chemical structure similar ligands, mono-β-diketone (p-methoxylbenzoyl)trifluoroacetone (MBTF) and bis-β-diketone 1,2-bis(4,4'-bis(4,4,4-trifluoro-1,3-dioxobutyl))phenoxyl ethane (BTPE) have been designed and prepared for the purpose of building the relationships between the structures and luminescence properties of Eu(III) complexes. Structures of their Eu(III) complexes [Eu(MBTF)3(DMSO)(H2O)] and [Eu2(BTPE)3(DMSO)4] have been defined by single crystal X-ray crystallography. The mono-β-diketone complex [Eu(MBTF)3(DMSO)(H2O)] is a mononuclear structure, the central Eu(III) ion is coordinated by eight oxygen atoms from three ligands and two solvents, in an distorted trigonal-dodecahedral (8-TDH) geometry. Whereas, the bis-β-diketone complex [Eu2(BTPE)3(DMSO)4] adopts triple-stranded dinuclear structure in which the two Eu(III) are helically wrapped by three bis-bidentate ligands, and each Eu(III) ion is eight-coordinated by six oxygen atoms from the ligands and two oxygen atoms from the coordinated DMSO molecules, in a distorted square-antiprismatic (8-SAP) geometry. The photophysical properties related to the electronic transition are characterized by the absorbance spectra, the emission spectra, the emission quantum yields, the emission lifetimes, and the radiative (kr) and nonradiative rate constants (knr). The mono-β-diketone complex [Eu(MBTF)3(DMSO)(H2O)] offers a relatively high emission quantum yield (38%, in solid) compared to that observed in the bis-β-diketone complex [Eu2(BTPE)3(DMSO)4] (25%, in solid). This enhancement of emission quantum yield in mono-β-diketone complex can be attributed to its lower site symmetry around the Eu(III) ion, lower non-radiative rate constant and higher energy transfer efficiency from ligand to metal ion.
    Physical Chemistry Chemical Physics 05/2015; 17(24). DOI:10.1039/C5CP01392E · 4.49 Impact Factor
  • Guanghui An · Pengfei Yan · Jingwen Sun · Yuxin Li · Xu Yao · Guangming Li ·
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    ABSTRACT: The racemate-to-homochiral approach is a method to transform or separate a racemic mixture into homochiral compounds. This protocol, if without an external chiral source, is categorized into chiral symmetry breaking. The resolution processes without chiral induction are highly important for the investigation of the origin of homochirality in life, pharmaceutical synthesis, the chemical industry and materials science. Besides the studies on the models and mechanisms used to explain the racemate-to-homochiral approach which may give the probable origin of homochirality in life, recent developments in this field have been plotted towards the separation of enantiomers for the synthesis of pharmaceuticals and chiral chemicals. Direct synthesis of chiral metal–organic framework (MOF) coordination polymers has been achieved as well. In this highlight, we will disclose the comparison of spontaneous resolution and chiral symmetry breaking resolution, and describe the evolution of models and mechanisms for chiral symmetry breaking resolution and its applications in enantiomer resolution and materials science.
    CrystEngComm 04/2015; 17(24). DOI:10.1039/C5CE00402K · 4.03 Impact Factor
  • Yumei Yue · Pengfei Yan · Jingwen Sun · Guangfeng Hou · Guangming Li ·
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    ABSTRACT: Three new Salen-type lanthanide coordination polymers, [Ln2(H2L)2(NO3)4(CH3O)2]n (Ln = Sm (1), Eu (2) and Lu (3); H2L = N,N’-bis(salicylidene)- 1,4-butanediamine), have been synthesized by a solvothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra and thermogravimetric analysis. Single-crystal X-ray diffraction studies reveal that complexes 1-3 are isostructural 2D coordination polymers based on dinuclear units, where the μ2-(methoxy-O)2-bridged Ln2O2 cores are linked by four Salen-type ligands in a bidentate mode. Each lanthanide ion is eight-coordinated by eight oxygen atoms, forming a distorted dodecahedral geometry. Luminescence analysis in the solid state at room temperature indicates that complex 1 exhibits the co-luminescence of the ligand and SmIII ions and complex 2 shows the characteristic red luminescence of EuIII ions. Furthermore, the energy transfer mechanisms are described and discussed.
    Polyhedron 04/2015; 94. DOI:10.1016/j.poly.2015.04.018 · 2.01 Impact Factor
  • Fang Luan · Tianqi Liu · Pengfei Yan · Xiaoyan Zou · Yuxin Li · Guangming Li ·
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    ABSTRACT: A series of three salen-type lanthanide complexes, e.g., [Dy4(L)2(HL)2Cl2(μ3-OH)2]2Cl2(OH)2·3CH3CH2OH·H2O (1) and [Ln4(L)2(HL)2Cl2(μ3-OH)2]Cl2·5CH3OH·4CH2Cl2 (Ln = Tb(III), 2; Ho(III), 3) have been isolated by the reactions of H2L (H2L = N,N'-bis(3-methoxysalicylidene)cyclohexane-1,2-diamine) with LnCl3·6H2O. X-ray crystallographic analysis reveals that all complexes 1-3 are isostructural, in which four Ln ions and eight O atoms form the distorted defective dicubane {Dy4O8} cores. Magnetic studies indicate that complex 1 exhibits two slow magnetic relaxation processes with effective energy barrier Ueff = 55.71 K under a zero direct-current field, which is attributed to the two coordination geometries of the Dy(III) ions with a salen-type ligand and coordination of a chloride counterion. It represents the highest energy barrier among the salen-type tetranuclear lanthanide single-molecule magnets.
    Inorganic Chemistry 03/2015; 54(7). DOI:10.1021/acs.inorgchem.5b00061 · 4.76 Impact Factor
  • Yanping Dong · Pengfei Yan · Xiaoyan Zou · Tianqi Liu · Guangming Li ·
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    ABSTRACT: A series of four β-diketone mononuclear dysprosium complexes, namely, Dy(EIFD)3(H2O)·CH2Cl2 (1), Dy(EIFD)3(DMF)·CH2Cl2 (2), Dy(EIFD)3(DMSO) (3), and Dy(EIFD)3(TPPO) (4) (EIFD: 1-(1-ethyl-1H-indol-3-yl)-4,4,4-trifluorobutane-1,3-dione, TPPO: triphenylphosphine oxide) have been isolated by the reactions of a newly designed β-diketone EIFD, DyCl3·6H2O and DMF, DMSO, TPPO, respectively. X-ray crystallographic analysis reveals that complexes 1−4 are isomorphic mononuclear structure in which the Dy(III) ion is rarely seven-coordinated with C3v geometry. Magnetic studies indicate that all complexes 1−4 are single-molecule magnets. The correlations between magnetism and the distortion of the coordination symmetry around the Dy(III) ions have been investigated. Notably, the quantum tunneling of magnetization (QTM) which universally existed in the lanthanide complexes have been effectively suppressed in this system more related to the less deviation from the ideal C3v symmetry.
    03/2015; 3(17). DOI:10.1039/C5TC00321K
  • Meiqi Zhang · Hongfeng Li · Peng Chen · Wenbin Sun · Lei Zhang · Pengfei Yan ·
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    ABSTRACT: Self-assembly reaction of 2-aldehyde-8-hydroxyquinoline, tris(hydroxymethyl)aminomethane and LnCl(3)center dot 6H(2)O affords a series of mononuclear lanthanide complexes Ce(baho)(2)center dot Et2O (1) (H(2)baho = 2,8-bis(2-(8-hydroxylquinolinyl))-1-aza-5-hydroxymethyl-3,7-dioxabicyclo[3.3.0]octane), DY(nhm)(2)Cl center dot 0.5H(2)O (2) and Ln(nhm)(2)Cl center dot 0.5C(6)H(14) (Ln = Ho (3), Er (4), Yb (5) and Hnhm = N-(2-(8-hydroxylquinolinyl)methylene)(trishydroxymethyl)methylamine. The crystal structures have been determined by Xray crystallographic analysis, and the tetravalence of Ce in 1 has been proven by XPS. Interestingly, the positive charge of Ce4+ ion in 1 is neutralized by two deprotonated baho(2-) ligands, while two deprotonated nhm(-) ligands and one Cl- compensate the positive charge of Ln(3+) ions in 2-5. Complex 5 exhibit essential NIR luminescence of Yb3+ ion with lifetime of 17.64 mu s in solid and 9.96 mu s in CH3OH solution.
    Journal of Molecular Structure 02/2015; 1081. DOI:10.1016/j.molstruc.2014.10.033 · 1.60 Impact Factor
  • Yumei Yue · Jingwen Sun · Pengfei Yan · Guangming Li ·
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    ABSTRACT: Variable-temperature dc magnetic susceptibility shows weak long-range order of chain of magnetization.•The dynamic susceptibility exhibits a typical of SMM behavior.•The Cole–Cole curves show the presence of at least two relaxation processes at a low temperature.•We report a Salen-type dysprosium complex that represents pure 4f SIMs with 1D ionic coordination network.
    Inorganic Chemistry Communications 01/2015; 51. DOI:10.1016/j.inoche.2014.11.007 · 1.78 Impact Factor
  • Yumei Yue · Pengfei Yan · Jingwen Sun · Guangming Li ·
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    ABSTRACT: A new flexible Salen-type dysprosium coordination polymer, [Dy2(H2L)2(NO3)4(CH3O)2]n (1) (H2L = N,N'-bis(salicylidene)-1,4-butane-diamine), has been synthesized by a solvothermal method. The single-crystal X-ray diffraction studies reveal that complex 1 features a two dimension (2D) network structure with rare dinuclear units. Each Dy(III) ion is eight-coordinated where the μ2-(OCH3)2 bridged Dy2O2 cores are linked by four Salen-type ligands in bidentate fashion. Magnetic studies reveal that complex 1 presents antiferromagnetic interactions between Dy(III) centers and exhibits the frequency dependent peaks, a behavior characteristic of a single-molecule magnet.
    Inorganic Chemistry Communications 01/2015; 54. DOI:10.1016/j.inoche.2015.01.031 · 1.78 Impact Factor
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    ABSTRACT: One Ag+ homometallic complex [Ag4(pzdc)2]·H2O (1), and five Ln-Ag heterometallic complexes, namely, [Gd2Ag6(pzdc)6(H2O)9]·8H2O (2) and [LnAg(pzdc)2(H2O)2]·2H2O [Ln = Tb (3), Dy (4), Ho (5), Er (6)] based on pyrazine-2,3-dicarboxylate (pzdc2-) have been synthesized under room temperature. Complex 1 exhibits 3D metal-organic framework by Ag2 ions connecting 1D square columns consisting of Ag1 ions and pzdc2- ligands, possessing a unique trinodal net with {42·6}{43}{45·64·83·103} topology. Complex 2 displays a 3D heterometal-organic framework with a novel 12-nodal topological net constructed by Gd1 ions linking the adjacent Ag-pzdc2- anion layers. Complexes 3-6 are isostuctural 2D Ln-Ag heterometallic coordination frameworks featuring uninodal 4-connected net with {44·62} topology. Magnetic analyses suggest that complexes 4 and 6 exhibit field-dependent slow magnetic relaxation, and complex 6 represents the first slow magnetic relaxation behavior existing in Er3+-based 2D heterometallic coordination framework.
    Crystal Growth & Design 01/2015; 15(3):150129090917005. DOI:10.1021/cg501644z · 4.89 Impact Factor
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    Fang Luan · Pengfei Yan · Jing Zhu · Tianqi Liu · Xiaoyan Zou · Guangming Li ·
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    ABSTRACT: Four isomorphic tetranuclear lanthanide complexes, namely [Ln4(L)2(HL)2(NO3)2(OH)2](NO3)2·4H2O (Ln = Dy (); Tb (); Ho (); Er ()), constructed using hexadentate salen-type ligand N,N'-bis(3-methoxy-salicylidene)cyclohexane-1,2-diamine, have been isolated. X-ray crystallographic analysis reveals that all of the complexes are of discrete tetranuclear structure with a unique {Ln4O8} core in which four lanthanide ions are coplanar in a rhombic frame. There are two crystallographically unequivalent lanthanide ions, that is the Ln1(III) ion which is nine-coordinated in a monocapped square-antiprismatic geometry of the C4v point group and the Ln2(III) ion which is eight-coordinated in a distorted bicapped trigonal-prismatic geometry of the C2v point group. Magnetic analysis reveals that complex exhibits two slow magnetic relaxations with the highest energy barrier among the reported tetranuclear salen-type dysprosium SMMs. This further extends the available SMMs of salen-type lanthanide complexes.
    Dalton Transactions 01/2015; 44(9). DOI:10.1039/c4dt02607a · 4.20 Impact Factor
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    ABSTRACT: Poly(phenylene vinylene)/polyvinyl alcohol/Ag (PPV/PVA/Ag) composite nanofibers with excellent photoelectric properties were prepared by coaxial electrospinning using PPV/PVA as the shell and Ag nanoparticles (NPs) as the core, Ag NPs aqueous solution was prepared by the reduction method. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that Ag NPs are of a face-centered cubic structure, with an average diameter of 46 nm and the composite nanofibers have uniform and continuous morphology. With increasing Ag content, the diameters of the composite nanofibers decreased from 653 nm to 250 nm. The X-ray diffraction (XRD) patterns verified that in the composite nanofibers, the Ag NPs are not transformed. In the photoluminescence spectra, the PPV/PVA/Ag composite nanofibers presented red-shift compared with PPV/PVA nanofibers. Under illumination, the as-prepared PPV/PVA/Ag composite nanofibers exhibited relatively high photocurrent intensity.
    01/2015; DOI:10.1515/polyeng-2014-0251
  • wenyi chu · Qingyan Sun · Xu Yao · Pengfei Yan · Guanghui An · Guangming Li ·

    RSC Advances 01/2015; DOI:10.1039/C5RA17358B · 3.84 Impact Factor
  • Hui XU · Dongxue Ding · Zhen Zhang · Ying Wei · Pengfei Yan ·
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    ABSTRACT: Two quaternary ambipolar phosphine oxide host materials, 9-(4-(9-(4′-(2-(diphenylphosphoryl)phenoxy)biphenyl-4-yl)-9H-fluoren-9-yl)phenyl)-9H-carbazole (9CzFDPESPO) and 9-(4-(9-(3′-(diphenylphosphoryl)-4′-(2-(diphenylphosphoryl)phenoxy)biphenyl-4-yl)-9H-fluoren-9-yl)phenyl)-9H-carbazole (9CzFDPEPO), were designed and prepared with mixed indirect and multi-insulating linkages to investigate the spatial effect on the electroluminescence performance of high-energy-gap hosts in blue phosphorescence and thermally activated delayed fluorescence light-emitting diodes (PHOLEDs and TADF OLEDs), in comparison to a ternary analogue 9-(4-(9-(4-(diphenylphosphoryl)phenyl)-9H-fluoren-9-yl)phenyl)-9H-carbazole (9CzFSPO). The donor-acceptor (D-A) distance in 9CzFDPESPO is elongated through the involvement of diphenylene as a π-extender, while the second phosphine oxide acceptor on diphenylene of 9CzFDPEPO is utilized to make its D-A distance comparable to that of 9CzFSPO. The single-molecular optoelectronic properties of these three hosts were uniform, owing to the effectively suppressed intramolecular electronic coupling by indirect and multi-insulating linkages. Their similar high triplet energy of 3.0 eV and the suitable energy levels of the highest occupied and the lowest unoccupied molecular orbitals around -6.1 and -2.5 eV, respectively, provide effective energy transfer and carrier injection. In contrast, 9CzFDPESPO shows the highest hole mobility owing to its longest D-A distance, directly indicating the spatial effect. As expected, with the most effectively suppressed spatial effect, 9CzFDPESPO endowed its blue phosphorescence and TADF devices with a state-of-the-art performance, e.g. external quantum efficiencies of 22.5% and 16.7%, respectively, which were the best results for quaternary host materials reported so far. This journal is
    Journal of Materials Chemistry C 01/2015; 3(43). DOI:10.1039/C5TC02726H · 4.70 Impact Factor
  • Xiaoyan Zou · Pengfei Yan · Yanping Dong · Fang Luan · Guangming Li ·

    RSC Advances 01/2015; DOI:10.1039/C5RA18244A · 3.84 Impact Factor