Monomer and metallopolymer compounds of Tb(III) as precursors for OLEDs (original) (raw)
Related papers
Current manufacturing technologies for OLEDs involve the use of expensive high vacuum techniques and call for thermal stability requirements which are not fulfilled by many materials. These problems disappear when the OLED films are deposited directly from solution. In this study, we have synthesized, modelled by semi-empirical quantum chemistry methods and characterized the optical properties of two novel Tb(III) complexes with carboxylic acids, which can be readily used as "complex-only" emissive layers in wet-processed OLEDs. Upon excitation in the UV region, very efficient energy transfer from the ligands to Tb 3+ takes place, giving rise to intense green emission, both in powder and as a thin film. The good quantum efficiencies (31.3% and 24.7%, respectively) and adequate thin film forming properties make these materials promising chromophores for cost-effective OLEDs.
Luminescent Terbium Complexes with Polymer Ligands
Collection of Czechoslovak Chemical Communications, 2004
Alternating and statistical copolymers of 9-vinylcarbazole with diethyl fumarate (1), diethyl maleate (2), methacrylic acid (3), maleic anhydride (4), or maleic acid (5) were synthesized and characterized. These copolymers were tested as polymer ligands, that might be able to suppress the environmental vibronic quenching of a lanthanide ion and, simultaneously, to function as energy donors in the ligand-to-metal energy transfer processes. Time-resolved luminescence of a series of [Tb(III)-ligand] complexes in common and deuterated solvents revealed that the complexing properties of copolymers 3 or 5 are stronger than those of 1 or 2. Consequently, the strong binding affinity decreases the ligand-metal (donor-acceptor) distance and gives rise to an efficient ligand-to-metal energy transfer. Thus, the intensities of the long-lived emission (5D4→7F6, 5D4→7F5, 5D4→7F4, 5D4→7F3) of the [Tb(III)-3], [Tb(III)-5], and [Tb(III)-1] or [Tb(III)-2] complexes were found to be eight times, five t...
Dalton transactions (Cambridge, England : 2003), 2015
In the series of homo-leptic trinuclear complexes {[Ln3(L)4Cl4(MeOH)(H2O)]·Cl} (Ln = La, ; Ln = Eu, ; Ln = Tb, or Ln = Gd, ) self-assembled from the allyl-modified benzimidazole-type ligand HL (4-allyl-2-(1H-benzo[d]imidazol-2-yl)-6-methoxyphenol) and LnCl3·6H2O, a suitable energy level match endows efficient green luminescence (Φoverall = 72%) of Tb3-arrayed complex . The copolymerization between each of these complex monomers and C[double bond, length as m-dash]C-containing MMA (methyl methacrylate) or NBE (norbornene) shows that degradative chain transfer of the terminal four flexible allyl groups within restrains their radical polymerization with MMA while it does not hinder their effective ring-opening metathesis polymerization (ROMP) with NBE. Thus, two kinds of PMMA-supported doping hybrid materials 1@PMMA, 2@PMMA, 3@PMMA and 4@PMMA and PNBE-supported metallopolymer-type hybrid materials Poly(NBE-1), Poly(NBE-2), Poly(NBE-3) and Poly(NBE-4) are obtained, respectively. Especia...
Terbium Polyoxometalate Organic Complexes: Correlation of Structure with Luminescence Properties
Angewandte Chemie International Edition, 2010
The investigation of polyoxometalates (POMs) continues to provide interesting new molecules with properties relevant to a wide variety of applications. Of particular interest to us is the ability of lacunary POMs to act as ligands to other metals, affording complexes with novel electronic and magnetic behavior. [2] Lacunary POMs offer useful features as ligands, including their size, solubility, diamagnetic nature, arrangement of coordination sites, flexibility of coordination modes, and ability to rearrange. [3] Oxophilic trivalent lanthanoid (Ln) metal centers are particularly well-suited for binding to lacunary POMs, and examples of POM-ligated lanthanoid complexes with one or more lanthanoid metal are known. Lanthanoid complexes of organic ligands are more numerous and have relevance as luminescent molecular materials and as contrast agents for magnetic resonance imaging. However, complexes with both organic and POM ligands bound simultaneously to lanthanoid centers are rare, despite their potential as novel hybrid molecules that can combine the useful properties conveyed by both types of ligand.
Crystal structures and luminescent properties of terbium(III) carboxylates
Inorganica Chimica Acta, 2003
Single crystals of three terbium(III) carboxylates of formulae [Tb 2 (CH 3 COO) 6 (H 2 O) 4 ] ×/4H 2 O (1), [Tb 2 (CF 3 COO) 6 (H 2 O) 6 ] (2) and [Tb(Hoda) 3 ] ×/H 2 oda ×/H 2 O (3) (H 2 oda 0/2,2?-oxydiacetic acid) were obtained and their structures determined by X-ray crystallography. Compounds 1 and 2 are dimeric, in the former the terbium atoms are bound by two tridentate carboxylates in the m 2bridging mode, whereas in the latter the bridging is fourfold with all carboxylates in the syn Á/syn coordination mode. Compound 3 is mononuclear containing three tridentate Hoda anions, and consecutive units are linked by a network of H-bonds involving the interstitial molecules. The luminescence spectra of the carboxylates were analyzed in the solid state and in aqueous solution. Comparison of the emission lifetimes in H 2 O and D 2 O allowed the determination of the average value for q , the number of coordinated water molecules, being 9.2 for 1 and 2 and 3.6 for 3, respectively. The quenching effect of Cu(II) on the luminescence of the terbium(III) carboxylates was evaluated through the emission decay constants. From the addition of Cu(II) to an aqueous solution of 3, single crystals of polymeric [{Cu 3 Tb 2 (oda) 6 (H 2 O) 6 }×/12H 2 O] n (4) were isolated with completely quenched luminescence. Compound 4 exhibits an overall antiferromagnetic interaction. # (M. Perec).
Inorganica Chimica Acta, 2014
ABSTRACT Three ternary lanthanide complexes with o-bromobenzoic (o-BrBA), o-chlorobenzoic acid (o-ClBA) and 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ) have been synthesized. These complexes were characterized by elementary analysis, UV absorption spectroscopy and IR spectroscopy. The crystal structures of [Tb-2(TPTZ)(2)(o-BrBA)(4)(NO3)(2)(H2O)(2)] (1), [Tb-2(TPTZ)(2)(o-ClBA)(3)(NO3)(2)(H2O)(3)]center dot o-ClBA center dot C2H5OH center dot 2H(2)O (2) and [Sm-2(TPTZ)(2)(o-ClBA)(4)(NO3)(2)(H2O)(2)] (3) were determined by single-crystal X-ray diffraction, and they were all dinuclear complexes with the characteristic of triclinic and P-1 space group. The crystals 1 and 3 were isostructural, whose center ions were bridged by mu(2)-o-BrBA /mu(2)-o-ClBA ions and the coordinate number of the central metal ions were nine, composed by a eta(3)-TPTZ, two bridging bidentates and one monodentate o-BrBA (o-ClBA) ligand, a bidentate NO3 and a coordinated water molecule. But the structure of complex 2 was asymmetric and the two Tb(III) ions have different coordination surroundings. Furthermore, the luminescence spectra and luminescence lifetimes of three crystals were then measured. Besides, the two Tb(III) complexes exhibit high emission quantum efficiencies.
Russian Journal of Coordination Chemistry, 2006
With homoligand TbL 3 and heteroligand complexes TbL 3 (Q) n (HL = HSal (salicylic acid) and HPA (2-anilinobenzoic acid); Q = TPPO (triphenylphosphine oxide) and TOPO (tri(n-octyl)phosphine oxide); n = 1 or 2) as examples, it was shown that heteroligand complexation affects not only the thermal and photoluminescent properties but also the quality of films obtained by centrifugation: the root-mean-square roughness changes in the order TbL 3 Q > TbL 3 (Q) 2 ≈ TbL 3. This is due to different association degrees of the complexes in solution, which was confirmed by MALDI-TOF MS data.
Investigation of the energy transfer mechanism in OLEDs based on a new terbium β-diketonate complex
2012
This study is focused on the contribution of radiative and non-radiative processes to the electroluminescence emission of OLEDs based on a new terbium(III) complex: {Tris(acetylacetonate)[1,2,5]thiadiazole[3,4-f][1,10]phenanthroline}terbium(III) or [Tb(ACAC) 3 TDZP]. The effects of the energy transfer mechanism are discussed based on photoluminescence and electroluminescence measurements. The terbium complex showed an intense photoluminescence with high color purity in the green region, characteristics of the Tb(III) ion narrow line transitions. However, when used in a double-layer OLED its electroluminescence showed an orange broad band emission which can be attributed to the electrophosphorescence of the ligands and to an inefficient energy transfer from the organic ligand to the Tb(III) ion. Alternatively, devices with a Tb(III) complex acting as a dopant (7.6%) in a matrix of CBP used as the active layer showed an improvement in the energy transfer process, resulting in the appearance of the characteristic emission lines of the Tb(III) ion.
Journal of Molecular Liquids, 2018
The present work for the first time introduces PDA-based vesicles as convenient supporters of luminescent water insoluble Tb 3+ complexes. The specific cyclophanic structure of the ligands, where upper and lower calix[4]arene rims are decorated by nonyl-and chelating groups correspondingly provides both complex formation with Tb 3+ ions with the coordination of the latter via two 1,3-diketonate groups and self-or mixed aggregation of the complexes. The conditions of the self-aggregation of the Tb 3+ complexes are revealed, although the self-aggregates are unstable being converted into the nanosized precipitates which tend to further aggregation and phase separation. The complexes exhibit Tb(III)-centered luminescence which tends to change in time following the phase separation processes. The embedding of the Tb 3+ complexes into the PDA-based vesicles results in the mixed aggregates with significant Tb(III)-centered luminescence and significant colloidal stability. The latter arises from high negative electrokinetic potential values due to exterior carboxylic/carboxylate groups of the PDA vesicles.