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Kuwahara T, Ohtsu H, Tsuge K. Synthesis and Photophysical Properties of Silver(I) Coordination Polymers Bridged by Dimethylpyrazine: Comparison of Emissive Excited States between Silver(I) and Copper(I) Congeners. Inorg Chem 2024; 63:8120-8130. [PMID: 38653757 DOI: 10.1021/acs.inorgchem.4c00271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Highly luminescent silver(I) coordination polymers [Ag2X2(PPh3)2(Me2pyz)]n (X = I, Br, Cl; Me2pyz: 2,5-dimethylpyrazine) were prepared together with copper congeners [Cu2X2(PPh3)2(Me2pyz)]n (X = I, Br). All the complexes showed thermally activated delayed fluorescence from the charge-transfer states in the visible region, from blue to red. The isomorphous relationship among the complexes allowed a detailed discussion of the effect of halogenido ligands and crystal packing on their luminescence energy. The relaxation in the emissive excited states (ESs) was determined to be more remarkable in silver complexes than in copper complexes despite their isomorphous structures, and the electronic effect of halogenido ligands was comparable to the effect of relaxation in emissive ESs.
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Affiliation(s)
- Taiki Kuwahara
- Graduate School of Science and Engineering, University of Toyama, Toyama, Toyama 930-8555, Japan
| | - Hideki Ohtsu
- Graduate School of Science and Engineering, University of Toyama, Toyama, Toyama 930-8555, Japan
| | - Kiyoshi Tsuge
- Graduate School of Science and Engineering, University of Toyama, Toyama, Toyama 930-8555, Japan
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2
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Meyer M, Prescimone A, Constable EC, Housecroft CE. Introducing sterically demanding substituents and π-π-interactions into [Cu(P^P)(N^N)] + complexes. Dalton Trans 2024; 53:5453-5465. [PMID: 38414289 DOI: 10.1039/d4dt00276h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
A series of ten N^N chelating ligands based on a 2,2'-bipyridine (bpy) metal-binding domain and featuring sterically hindering substituents in the 6- and 6,6'-positions has been synthesized and characterized. The ligands have been incorporated into a family of 15 heteroleptic complexes of type [Cu(P^P)(N^N)][PF6] where P^P is the wide bite-angle bisphosphane ligand bis(2(diphenylphosphanyl)phenyl)ether (POP) or (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane) (xantphos). Substituents in several of the N^N ligands ligands possess phenyl rings remotely tethered to enable intra- and intermolecular π-π-interactions in the [Cu(P^P)(N^N)]+ cations. Single crystal X-ray structures of 12 complexes are reported. The effects of the functional groups in the bpy ligand on the photophysical properties of the complexes have been studied; solid-state emission maxima range from 518 to 567 nm. Values of the solid-state photoluminescence quantum yields (PLQYs) of the [Cu(P^P)(N^N)][PF6] compounds respond to the nature of the N^N ligand. In general, we observed that the [Cu(P^P)(N^N)]+ complexes containing 6,6'-disubstituted complexes with phenyl moieties connected via a CH2CH2 or CH2CH2CH2 spacer to the bpy domain have the highest values of PLQY. The most significant compounds are [Cu(POP)((2-PhEt)2bpy)][PF6] (PLQY = 67%) and [Cu(POP)((3-PhPr)2bpy)][PF6] (PLQY = 72%) where (2-PhEt)2bpy = 6,6'-bis(2-phenylethyl)-2,2'-bipyridine and (3-PhPr)2bpy = 6,6'-bis(3-phenylpropyl)-2,2'-bipyridine. These PLQY values are among the best performing previously reported families of [Cu(P^P)(N^N)][PF6] compounds.
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Affiliation(s)
- Marco Meyer
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Edwin C Constable
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Catherine E Housecroft
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
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3
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Vásquez B, Bayas M, Dreyse P, Palma JL, Cabrera AR, Rossin E, Natali M, Saldias C, González-Pavez I. Synthesis and Characterization of Iridium(III) Complexes with Substituted Phenylimidazo(4,5- f)1,10-phenanthroline Ancillary Ligands and Their Application in LEC Devices. Molecules 2023; 29:53. [PMID: 38202636 PMCID: PMC10779995 DOI: 10.3390/molecules29010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 01/12/2024] Open
Abstract
In this work, we report on the synthesis and characterization of six new iridium(III) complexes of the type [Ir(C^N)2(N^N)]+ using 2-phenylpyridine (C1-3) and its fluorinated derivative (C4-6) as cyclometalating ligands (C^N) and R-phenylimidazo(4,5-f)1,10-phenanthroline (R = H, CH3, F) as the ancillary ligand (N^N). These luminescent complexes have been fully characterized through optical and electrochemical studies. In solution, the C4-6 series exhibits quantum yields (Ф) twice as high as the C1-3 series, exceeding 60% in dichloromethane and where 3MLCT/3LLCT and 3LC emissions participate in the phenomenon. These complexes were employed in the active layer of light-emitting electrochemical cells (LECs). Device performance of maximum luminance values of up to 21.7 Lx at 14.7 V were observed for the C2 complex and long lifetimes for the C1-3 series. These values are counterintuitive to the quantum yields observed in solution. Thus, we established that the rigidity of the system and the structure of the solid matrix dramatically affect the electronic properties of the complex. This research contributes to understanding the effects of the modifications in the ancillary and cyclometalating ligands, the photophysics of the complexes, and their performance in LEC devices.
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Affiliation(s)
- Bárbara Vásquez
- Departamento de Química Física, Facultad de Química y de Farmacia, Pontifica Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul 7820436, Chile;
- Departamento de Química, Facultad de Ciencias Naturales, Matemática y del Medio Ambiente, Universidad Tecnológica Metropolitana, Las Palmeras 3360, Ñuñoa, Santiago 7800003, Chile
| | - Max Bayas
- Departamento de Química Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul 7820436, Chile (A.R.C.)
| | - Paulina Dreyse
- Department of Chemistry, Faculty of Science, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800003, Chile
| | - Juan Luis Palma
- Engineering School, Universidad Central de Chile, Santa Isabel 1186, Santiago 8330601, Chile
- Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago 9170124, Chile
| | - Alan R. Cabrera
- Departamento de Química Inorgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul 7820436, Chile (A.R.C.)
| | - Elena Rossin
- Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Università degli Studi di Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy (M.N.)
- Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via F. Marzolo 1, 35131 Padova, Italy
| | - Mirco Natali
- Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Università degli Studi di Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy (M.N.)
| | - Cesar Saldias
- Departamento de Química Física, Facultad de Química y de Farmacia, Pontifica Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul 7820436, Chile;
| | - Iván González-Pavez
- Departamento de Química, Facultad de Ciencias Naturales, Matemática y del Medio Ambiente, Universidad Tecnológica Metropolitana, Las Palmeras 3360, Ñuñoa, Santiago 7800003, Chile
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Jaros SW, Sokolnicki J, Siczek M, Smoleński P. Strategy for an Effective Eco-Optimized Design of Heteroleptic Cu(I) Coordination Polymers Exhibiting Thermally Activated Delayed Fluorescence. Inorg Chem 2023. [PMID: 38010323 DOI: 10.1021/acs.inorgchem.3c01908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The new series of copper(I) coordination polymers [Cu(N-N)(μ-PTA)]n[PF6]n {N-N = dmbpy (1), bpy (2), ncup (3), and phen (4)} were generated by straightforward reaction in solution or through a mechanochemical route, of [Cu(MeCN)4][PF6] with 1,3,5-triaza-7-phosphaadamantane (PTA) and the corresponding polypyridines, namely, 5,5'-dimethyl-2,2'-bipyridine (dmbpy), 2,2'-bipyridine (bpy), 2,9-dimethyl-1,10-phenanthroline (ncup), and 1,10-phenanthroline (phen). The compounds were obtained as air-stable solids and fully characterized by IR, NMR spectroscopy, and elemental analyses. The molecular structures were confirmed by single-crystal X-ray diffraction analysis (for 1, 2, and 4), revealing infinite one-dimensional (1D) linear chains driven by μ-PTA N,P-linkers. All tested Cu(I) polymeric compounds show emission at room temperature, which was attributed to thermally activated delayed fluorescence (TADF). Evidence of the involvement of the excited singlet state in the emission process is presented. Comparing the photophysical properties of 1 and 2 as well as 3 and 4, of which 1 and 3 have a stiffened structure, by introducing a methyl group to one of the ligands, we demonstrate how TADF properties depend on molecular rigidity. It is shown that stiffening of the structure reduces the flattening distortion around the Cu(I) center in the 3MLCT state. As a result, the ΔE(S1-T1) energy gap becomes smaller and the fluorescence quantum yield increases without significantly extending the emission lifetime. In particular, the ΔE(S1-T1) values for complexes 1 and 3 are among the shortest reported in the scientific literature, 253 and 337 cm-1, and the TADF lifetimes are τ(300 K) = 5.7 and 4.2 μs, respectively. The fluorescence quantum yields for these complexes are measured to be ΦPL(300 K) = 70 and 80%.
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Affiliation(s)
- Sabina W Jaros
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland
| | - Jerzy Sokolnicki
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland
| | - Miłosz Siczek
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland
| | - Piotr Smoleński
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland
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Arkhypchuk AI, Tran TT, Charaf R, Hammarström L, Ott S. Mechanistic Insights and Synthetic Explorations of the Photoredox-Catalyzed Activation of Halophosphines. Inorg Chem 2023; 62:18391-18398. [PMID: 37853683 PMCID: PMC10647117 DOI: 10.1021/acs.inorgchem.3c01946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Indexed: 10/20/2023]
Abstract
The light-driven activation of halophosphines R2PX (R = alkyl- or aryl, X = Cl, Br) by an IrIII-based photocatalyst is described. It is shown that initially formed secondary phosphines R2PH react readily with the remaining R2PX in a parent-child reaction to form diphosphines R2P-PR2. Aryl-containing diphosphines can be further reduced to secondary phosphines RAr2PH under identical photoredox conditions. Dihalophosphines RPX2 are also activated by the photoredox protocol, giving rise to unusual 3-, 4-, and 5-membered cyclophosphines. Transient absorption studies show that the excited state of the Ir photocatalyst is reductively quenched by the DIPEA (N,N-di-iso-propylethylamine) electron donor. Electron transfer to R2PX is however unexpectedly slow and cannot compete with recombination with the oxidized donor DIPEA•+. As DIPEA is not a perfectly reversible donor, a small proportion of the total IrII population escapes recombination, providing the reductant for the observed transformations.
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Affiliation(s)
- Anna I. Arkhypchuk
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Thuan T. Tran
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Rima Charaf
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Leif Hammarström
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
| | - Sascha Ott
- Department of Chemistry—Ångström, Laboratory Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden
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Beaudelot J, Oger S, Peruško S, Phan TA, Teunens T, Moucheron C, Evano G. Photoactive Copper Complexes: Properties and Applications. Chem Rev 2022; 122:16365-16609. [PMID: 36350324 DOI: 10.1021/acs.chemrev.2c00033] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Photocatalyzed and photosensitized chemical processes have seen growing interest recently and have become among the most active areas of chemical research, notably due to their applications in fields such as medicine, chemical synthesis, material science or environmental chemistry. Among all homogeneous catalytic systems reported to date, photoactive copper(I) complexes have been shown to be especially attractive, not only as alternative to noble metal complexes, and have been extensively studied and utilized recently. They are at the core of this review article which is divided into two main sections. The first one focuses on an exhaustive and comprehensive overview of the structural, photophysical and electrochemical properties of mononuclear copper(I) complexes, typical examples highlighting the most critical structural parameters and their impact on the properties being presented to enlighten future design of photoactive copper(I) complexes. The second section is devoted to their main areas of application (photoredox catalysis of organic reactions and polymerization, hydrogen production, photoreduction of carbon dioxide and dye-sensitized solar cells), illustrating their progression from early systems to the current state-of-the-art and showcasing how some limitations of photoactive copper(I) complexes can be overcome with their high versatility.
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Affiliation(s)
- Jérôme Beaudelot
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Samuel Oger
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
| | - Stefano Peruško
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Organic Synthesis Division, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020Antwerp, Belgium
| | - Tuan-Anh Phan
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Titouan Teunens
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium.,Laboratoire de Chimie des Matériaux Nouveaux, Université de Mons, Place du Parc 20, 7000Mons, Belgium
| | - Cécile Moucheron
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Gwilherm Evano
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
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7
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Recent developments of photoactive Cu(I) and Ag(I) complexes with diphosphine and related ligands. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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Paderina A, Melnikov A, Slavova S, Sizov V, Gurzhiy V, Petrovskii S, Luginin M, Levin O, Koshevoy I, Grachova E. The Tail Wags the Dog: The Far Periphery of the Coordination Environment Manipulates the Photophysical Properties of Heteroleptic Cu(I) Complexes. Molecules 2022; 27:2250. [PMID: 35408648 PMCID: PMC9000333 DOI: 10.3390/molecules27072250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 11/16/2022] Open
Abstract
In this work we show, using the example of a series of [Cu(Xantphos)(N^N)]+ complexes (N^N being substituted 5-phenyl-bipyridine) with different peripheral N^N ligands, that substituents distant from the main action zone can have a significant effect on the physicochemical properties of the system. By using the C≡C bond on the periphery of the coordination environment, three hybrid molecular systems with -Si(CH3)3, -Au(PR3), and -C2HN3(CH2)C10H7 fragments were produced. The Cu(I) complexes thus obtained demonstrate complicated emission behaviour, which was investigated by spectroscopic, electrochemical, and computational methods in order to understand the mechanism of energy transfer. It was found that the -Si(CH3)3 fragment connected to the peripheral C≡C bond changes luminescence to long-lived intra-ligand phosphorescence, in contrast to MLCT phosphorescence or TADF. The obtained results can be used for the design of new materials based on Cu(I) complexes with controlled optoelectronic properties on the molecular level, as well as for the production of hybrid systems.
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Affiliation(s)
- Aleksandra Paderina
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
| | - Alexey Melnikov
- Centre for Nano- and Biotechnologies, Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia;
| | - Sofia Slavova
- Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria;
| | - Vladimir Sizov
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
| | - Vladislav Gurzhiy
- Institute of Earth Sciences, St. Petersburg University, 199034 St. Petersburg, Russia;
| | - Stanislav Petrovskii
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
| | - Maksim Luginin
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
| | - Oleg Levin
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
| | - Igor Koshevoy
- Department of Chemistry, University of Eastern Finland, 80101 Joensuu, Finland;
| | - Elena Grachova
- Institute of Chemistry, St. Petersburg University, Universitetskii pr. 26, 198504 St. Petersburg, Russia; (A.P.); (V.S.); (S.P.); (M.L.); (O.L.)
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Housecroft CE, Constable EC. TADF: Enabling luminescent copper(i) coordination compounds for light-emitting electrochemical cells. JOURNAL OF MATERIALS CHEMISTRY. C 2022; 10:4456-4482. [PMID: 35433007 PMCID: PMC8944257 DOI: 10.1039/d1tc04028f] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/11/2021] [Indexed: 05/07/2023]
Abstract
The last decade has seen a surge of interest in the emissive behaviour of copper(i) coordination compounds, both neutral compounds that may have applications in organic light-emitting doides (OLEDs) and copper-based ionic transition metal complexes (Cu-iTMCs) with potential use in light-emitting electrochemical cells (LECs). One of the most exciting features of copper(i) coordination compounds is their possibility to exhibit thermally activated delayed fluorescence (TADF) in which the energy separation of the excited singlet (S1) and excited triplet (T1) states is very small, permitting intersystem crossing (ISC) and reverse intersystem crossing (RISC) to occur at room temperature without the requirement for the large spin-orbit coupling inferred by the presence of a heavy metal such as iridium. In this review, we focus mainly in Cu-iTMCs, and illustrate how the field of luminescent compounds and those exhibiting TADF has developed. Copper(i) coordination compounds that class as Cu-iTMCs include those containing four-coordinate [Cu(P^P)(N^N)]+ (P^P = large-bite angle bisphosphane, and N^N is typically a diimine), [Cu(P)2(N^N)]+ (P = monodentate phosphane ligand), [Cu(P)(tripodal-N3)]+, [Cu(P)(N^N)(N)]+ (N = monodentate N-donor ligand), [Cu(P^P)(N^S)]+ (N^S = chelating N,S-donor ligand), [Cu(P^P)(P^S)]+ (P^S = chelating P,S-donor ligand), [Cu(P^P)(NHC)]+ (NHC = N-heterocyclic carbene) coordination domains, dinuclear complexes with P^P and N^N ligands, three-coordinate [Cu(N^N)(NHC)]+ and two-coordinate [Cu(N)(NHC)]+ complexes. We pay particular attention to solid-state structural features, e.g. π-stacking interactions and other inter-ligand interactions, which may impact on photoluminescence quantum yields. Where emissive Cu-iTMCs have been tested in LECs, we detail the device architectures, and this emphasizes differences which make it difficult to compare LEC performances from different investigations.
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Affiliation(s)
- Catherine E Housecroft
- Department of Chemistry, University of Basel Mattenstrasse 24a, BPR 1096 4058-Basel Switzerland
| | - Edwin C Constable
- Department of Chemistry, University of Basel Mattenstrasse 24a, BPR 1096 4058-Basel Switzerland
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Zheng D, Huang TH, Luo C, Tang J. Structural characterization, DFT studies and luminescent properties of dinuclear copper(I)-diimine complexes with the S-shape configurations. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120639] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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11
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Lu Y, Li X, Wang J, Zhao F, Wang Y, He H, Wu Y. Synthesis, characterization and DFT studies of luminescent copper(I) complexes containing pyridine-imidazole ligands with tunable π-conjugation system via variation of polyaromatic groups. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Meyer M, Mardegan L, Tordera D, Prescimone A, Sessolo M, Bolink HJ, Constable EC, Housecroft CE. A counterion study of a series of [Cu(P^P)(N^N)][A] compounds with bis(phosphane) and 6-methyl and 6,6'-dimethyl-substituted 2,2'-bipyridine ligands for light-emitting electrochemical cells. Dalton Trans 2021; 50:17920-17934. [PMID: 34757348 PMCID: PMC8669729 DOI: 10.1039/d1dt03239a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/02/2021] [Indexed: 11/26/2022]
Abstract
The syntheses and characterisations of a series of heteroleptic copper(I) compounds [Cu(POP)(Mebpy)][A], [Cu(POP)(Me2bpy)][A], [Cu(xantphos)(Mebpy)][A] and [Cu(xantphos)(Me2bpy)][A] in which [A]- is [BF4]-, [PF6]-, [BPh4]- and [BArF4]- (Mebpy = 6-methyl-2,2'-bipyridine, Me2bpy = 6,6'-dimethyl-2,2'-bipyridine, POP = oxydi(2,1-phenylene)bis(diphenylphosphane), xantphos = (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane), [BArF4]- = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate) are reported. Nine of the compounds have been characterised by single crystal X-ray crystallography, and the consequences of the different anions on the packing interactions in the solid state are discussed. The effects of the counterion on the photophysical properties of [Cu(POP)(N^N)][A] and [Cu(xantphos)(N^N)][A] (N^N = Mebpy and Me2bpy) have been investigated. In the solid-state emission spectra, the highest energy emission maxima are for [Cu(xantphos)(Mebpy)][BPh4] and [Cu(xantphos)(Me2bpy)][BPh4] (λemmax = 520 nm) whereas the lowest energy λemmax values occur for [Cu(POP)(Mebpy)][PF6] and [Cu(POP)(Mebpy)][BPh4] (565 nm and 563 nm, respectively). Photoluminescence quantum yields (PLQYs) are noticeably affected by the counterion; in the [Cu(xantphos)(Me2bpy)][A] series, solid-state PLQY values decrease from 62% for [PF6]-, to 44%, 35% and 27% for [BF4]-, [BPh4]- and [BArF4]-, respectively. This latter series of compounds was used as active electroluminescent materials on light-emitting electrochemical cells (LECs). The luminophores were mixed with ionic liquids (ILs) [EMIM][A] ([EMIM]+ = [1-ethyl-3-methylimidazolium]+) containing the same or different counterions than the copper(I) complex. LECs containing [Cu(xantphos)(Me2bpy)][BPh4] and [Cu(xantphos)(Me2bpy)][BArF4] failed to turn on under the LEC operating conditions, whereas those with the smaller [PF6]- or [BF4]- counterions had rapid turn-on times and exhibited maximum luminances of 173 and 137 cd m-2 and current efficiencies of 3.5 and 2.6 cd A-1, respectively, when the IL contained the same counterion as the luminophore. Mixing the counterions ([PF6]- and [BF4]-) of the active complex and the IL led to a reduction in all the figures of merit of the LECs.
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Affiliation(s)
- Marco Meyer
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Lorenzo Mardegan
- Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain.
| | - Daniel Tordera
- Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain.
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Michele Sessolo
- Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain.
| | - Henk J Bolink
- Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain.
| | - Edwin C Constable
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
| | - Catherine E Housecroft
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR 1096, 4058 Basel, Switzerland.
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Mononuclear Copper(I) 3-(2-pyridyl)pyrazole Complexes: The Crucial Role of Phosphine on Photoluminescence. Molecules 2021; 26:molecules26226869. [PMID: 34833961 PMCID: PMC8620892 DOI: 10.3390/molecules26226869] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 12/02/2022] Open
Abstract
A series of emissive Cu(I) cationic complexes with 3-(2-pyridyl)-5-phenyl-pyrazole and various phosphines: dppbz (1), Xantphos (2), DPEPhos (3), PPh3 (4), and BINAP (5) were designed and characterized. Complexes obtained exhibit bright yellow-green emission (ca. 520–650 nm) in the solid state with a wide range of QYs (1–78%) and lifetimes (19–119 µs) at 298 K. The photoluminescence efficiency dramatically depends on the phosphine ligand type. The theoretical calculations of buried volumes and excited states explained the emission behavior for 1–5 as well as their lifetimes. The bulky and rigid phosphines promote emission efficiency through the stabilization of singlet and triplet excited states.
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14
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Synthesis, structures, DFT studies and luminescent properties of copper(I)-diimine complexes and application in yellow-green light-emitting diode. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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15
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Vinogradova KA, Shekhovtsov NA, Berezin AS, Sukhikh TS, Rogovoy MI, Artem'ev AV, Bushuev MB. Coordination-induced emission enhancement in copper(I) iodide coordination polymers supported by 2-(alkylsulfanyl)pyrimidines. Dalton Trans 2021; 50:9317-9330. [PMID: 34132730 DOI: 10.1039/d1dt00826a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
First examples of copper(i) complexes with 2-(alkylsulfanyl)pyrimidine ligands have been synthesized. Reactions of copper(i) iodide with 2-(methylsulfanyl)pyrimidine (L1) in various metal-to-ligand molar ratios in MeCN afford a ladder-type coordination polymer [Cu2L1I2]n with polymeric chains built from double-stranded (Cu2I2)n ribbons supported on both sides by μ2-N,S-L1 molecules. Although the second ligand, 2-(ethylsulfanyl)pyrimidine (L2), differs from L1 only by a methylene group, its reactions with copper(i) iodide in MeCN yield not only a congenerous coordination polymer, [Cu2L2I2]n, but also [CuL2I]n, in which a similar (Cu2I2)n ribbon is decorated by N-monodentate L2 molecules. Absorption spectra of all compounds represent an interplay of metal + iodine-to-ligand charge transfer (XMLCT) and ligand-centered (LC) and cluster-centered (CC) transitions, while the emission occurs from the excited states of XMLCT nature. The luminescence of [Cu2L1I2]n and [Cu2L2I2]n is blue-shifted and greatly enhanced in comparison with that of [CuL2I]n (quantum yields: 89% and 68% for [Cu2L1I2]n and [Cu2L2I2]nvs. 23% for [CuL2I]n at 77 K), which can be associated with a more rigid μ2-N,S coordination of 2-(alkylsulfanyl)pyrimidine ligands in [Cu2L1I2]n and [Cu2L2I2]n leading to a less distorted T1 state.
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Affiliation(s)
- Katerina A Vinogradova
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Nikita A Shekhovtsov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Alexey S Berezin
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Taisiya S Sukhikh
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Maxim I Rogovoy
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Alexander V Artem'ev
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
| | - Mark B Bushuev
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090, Russia.
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16
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Li C, Mackenzie CFR, Said SA, Pal AK, Haghighatbin MA, Babaei A, Sessolo M, Cordes DB, Slawin AMZ, Kamer PCJ, Bolink HJ, Hogan CF, Zysman-Colman E. Wide-Bite-Angle Diphosphine Ligands in Thermally Activated Delayed Fluorescent Copper(I) Complexes: Impact on the Performance of Electroluminescence Applications. Inorg Chem 2021; 60:10323-10339. [PMID: 34197094 DOI: 10.1021/acs.inorgchem.1c00804] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report a series of seven cationic heteroleptic copper(I) complexes of the form [Cu(P^P)(dmphen)]BF4, where dmphen is 2,9-dimethyl-1,10-phenanthroline and P^P is a diphosphine chelate, in which the effect of the bite angle of the diphosphine ligand on the photophysical properties of the complexes was studied. Several of the complexes exhibit moderately high photoluminescence quantum yields in the solid state, with ΦPL of up to 35%, and in solution, with ΦPL of up to 98%. We were able to correlate the powder photoluminescence quantum yields with the % Vbur of the P^P ligand. The most emissive complexes were used to fabricate both organic light-emitting diodes and light-emitting electrochemical cells (LECs), both of which showed moderate performance. Compared to the benchmark copper(I)-based LECs, [Cu(dnbp)(DPEPhos)]+ (maximum external quantum efficiency, EQEmax = 16%), complex 3 (EQEmax = 1.85%) showed a much longer device lifetime (t1/2 = 1.25 h and >16.5 h for [Cu(dnbp)(DPEPhos)]+ and complex 3, respectively). The electrochemiluminescence (ECL) properties of several complexes were also studied, which, to the best of our knowledge, constitutes the first ECL study for heteroleptic copper(I) complexes. Notably, complexes exhibiting more reversible electrochemistry were associated with higher annihilation ECL as well as better performance in a LEC.
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Affiliation(s)
- Chenfei Li
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Campbell F R Mackenzie
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Said A Said
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Amlan K Pal
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K.,Department of Chemistry, Indian Institute of Technology Jammu, Jagti Campus, Nagrota Bypass Road, Jammu, Jammu and Kashmir 181221, India
| | - Mohammad A Haghighatbin
- Department of Chemistry & Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Azin Babaei
- Instituto de Ciencia Molecular, Universidad de Valencia, Paterna 46980, Spain
| | - Michele Sessolo
- Instituto de Ciencia Molecular, Universidad de Valencia, Paterna 46980, Spain
| | - David B Cordes
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Alexandra M Z Slawin
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Paul C J Kamer
- Leibniz Institute for Catalysis, Albert-Einstein-Strasse 29a, Rostock 18059, Germany
| | - Henk J Bolink
- Instituto de Ciencia Molecular, Universidad de Valencia, Paterna 46980, Spain
| | - Conor F Hogan
- Department of Chemistry & Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
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17
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Emami M, Shahroosvand H, Bikas R, Lis T, Daneluik C, Pilkington M. Synthesis, Study, and Application of Pd(II) Hydrazone Complexes as the Emissive Components of Single-Layer Light-Emitting Electrochemical Cells. Inorg Chem 2021; 60:982-994. [PMID: 33404233 DOI: 10.1021/acs.inorgchem.0c03102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
For the first time, square planar Pd(II) complexes of hydrazone ligands have been investigated as the emissive components of light-emitting electrochemical cells (LECs). The neutral transition metal complex, [Pd(L1)2]·2CH3OH (1), (HL1 = (E)-N'-(phenyl(pyridin-2-yl)methylene)isonicotinhydrazide), was prepared and structurally characterized. Complex 1 displays quasireversible redox properties and is emissive at room temperature in solution with a λmax of 590 nm. As a result, it was subsequently employed as the emissive material of a single-layer LEC with configuration FTO/1/Ga/In, where studies reveal that it has a yellow color with CIE(x, y) = (0.33, 0.55), a luminance of 134 cd cm-2, and a turn-on voltage of 3.5 V. Protonation of the pendant pyridine nitrogen atoms of L1 afforded a second ionic complex [Pd(L1H)2](ClO4)2 (2) which is also emissive at room temperature with a λmax of 611 nm, resulting in an orange LEC with CIE(x, y) = (0.43, 0.53). The presence of mobile anions and cations in the second inorganic transition metal complex resulted in more efficient charge injection and transport which significantly improved the luminance and turn-on voltage of the device to 188.6 cd cm-2 and 3 V, respectively. This study establishes Pd(II) hydrazone complexes as a new class of materials whose emissive properties can be chemically tuned and provides proof-of-concept for their use in LECs, opening up exciting new avenues for potential applications in the field of solid state lighting.
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Affiliation(s)
- Marzieh Emami
- Group for Molecular Engineering of Advanced Functional Materials (GMA), Chemistry Department, University of Zanjan, 45371-38791 Zanjan, Iran
| | - Hashem Shahroosvand
- Group for Molecular Engineering of Advanced Functional Materials (GMA), Chemistry Department, University of Zanjan, 45371-38791 Zanjan, Iran
| | - Rahman Bikas
- Department of Chemistry, Faculty of Science, Imam Khomeini International University, 34148-96818 Qazvin, Iran
| | - Tadeusz Lis
- Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Cody Daneluik
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S3A1, Canada
| | - Melanie Pilkington
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S3A1, Canada
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18
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Positional Isomerism in the N^N Ligand: How Much Difference Does a Methyl Group Make in [Cu(P^P)(N^N)] + Complexes? Molecules 2020; 25:molecules25122760. [PMID: 32549279 PMCID: PMC7356218 DOI: 10.3390/molecules25122760] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 12/16/2022] Open
Abstract
The synthesis and structural characterization of 5,6′-dimethyl-2,2′-bipyridine (5,6′-Me2bpy) are reported, along with the preparations and characterizations of [Cu(POP)(5,6′-Me2bpy)][PF6] and [Cu(xantphos)(5,6′-Me2bpy)][PF6] (POP = bis(2-(diphenylphosphanyl)phenyl)ether, xantphos = 4,5-bis(diphenylphosphanyl)-9,9-dimethyl-9H-xanthene). Single-crystal X-ray structure determinations of [Cu(POP)(5,6′-Me2bpy)][PF6] and [Cu(xantphos)(5,6′-Me2bpy)][PF6] confirmed distorted tetrahedral copper(I) coordination environments with the 5-methylpyridine ring of 5,6′-Me2bpy directed towards the (C6H4)2O unit of POP or the xanthene unit of xantphos. In the xantphos case, this preference may be attributed to C–H…π interactions involving both the 6-CH unit and the 5-methyl substituent in the 5-methylpyridine ring and the arene rings of the xanthene unit. 1H NMR spectroscopic data indicate that this ligand orientation is also preferred in solution. In solution and the solid state, [Cu(POP)(5,6′-Me2bpy)][PF6] and [Cu(xantphos)(5,6′-Me2bpy)][PF6] are yellow emitters, and, for powdered samples, photoluminescence quantum yields (PLQYs) are 12 and 11%, respectively, and excited-state lifetimes are 5 and 6 μs, respectively. These values are lower than PLQY and τ values for [Cu(POP)(6,6′-Me2bpy)][PF6] and [Cu(xantphos)(6,6′-Me2bpy)][PF6], and the investigation points to the 6,6′-dimethyl substitution pattern in the bpy ligand being critical for enhancement of the PLQY.
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19
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Alkan-Zambada M, Constable EC, Housecroft CE. The Role of Percent Volume Buried in the Characterization of Copper(I) Complexes for Lighting Purposes. Molecules 2020; 25:molecules25112647. [PMID: 32517264 PMCID: PMC7321245 DOI: 10.3390/molecules25112647] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 12/19/2022] Open
Abstract
The usefulness of percent volume buried (%Vbur) as a readily quantifiable property is investigated with regard to [Cu(NN)(PP)]+ complexes of interest for lighting purposes. Photoluminescence quantum yields (PLQYs) and single crystal X-ray structures of 100 reported compounds were assembled, %Vbur of the ligand systems were calculated and analyzed for correlations. We found that increased shielding of the central Cu(I) cation relying on shared contributions of both (NN) and (PP) ligand systems led to increased PLQYs. These findings are of relevance for future characterizations of Cu(I)-based complexes and their photophysical behavior in the solid-state.
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Affiliation(s)
- Murat Alkan-Zambada
- Laboratory of Inorganic Synthesis and Catalysis, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), ISIC-LSCI, BCH 3305, 1015 Lausanne, Switzerland
- Correspondence:
| | - Edwin C. Constable
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland; (E.C.C.); (C.E.H.)
| | - Catherine E. Housecroft
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland; (E.C.C.); (C.E.H.)
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20
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Abstract
The syntheses and characterizations of the chelating ligand 6-chloro-6′-methyl-2,2′-bipyridine (6-Cl-6′-Mebpy) and of the copper(I) compounds [Cu(POP)(6-Cl-6′-Mebpy)][PF6] and [Cu(xantphos)(6-Cl-6′-Mebpy)][PF6] (POP = bis(2-(diphenylphosphanyl)phenyl)ether and xantphos = 4,5-bis(diphenylphosphanyl)-9,9-dimethyl-9H-xanthene) are described. The single crystal structures of both complexes were determined; the copper(I) ion is in a distorted tetrahedral environment and in [Cu(xantphos)(6-Cl-6′-Mebpy)][PF6], the disorder of the 6-Cl-6′-Mebpy ligand indicates there is no preference of the ‘bowl’-like cavity of the xanthene unit to host either the methyl or chloro-substituent, consistent with comparable steric effects of the two groups. The electrochemical and photophysical properties of [Cu(POP)(6-Cl-6′-Mebpy)][PF6] and [Cu(xantphos)(6-Cl-6′-Mebpy)][PF6] were investigated and are compared with those of the related compounds containing 6,6′-dichloro-2,2′-bipyridine or 6,6′-dimethyl-2,2′-bipyridine ligands. Trends in properties of the [Cu(P^P)(N^N)]+ complexes were consistent with 6-Cl-6′-Mebpy behaving as a combination of the two parent ligands.
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21
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Zeng Q, Li F, Chen Z, Yang K, Liu Y, Guo T, Shan GG, Su Z. Rational Design of Efficient Organometallic Ir(III) Complexes for High-Performance, Flexible, Monochromatic, and White Light-Emitting Electrochemical Cells. ACS APPLIED MATERIALS & INTERFACES 2020; 12:4649-4658. [PMID: 31916440 DOI: 10.1021/acsami.9b18162] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Highly efficient light-emitting electrochemical cells (LECs) have attracted tremendous interest because of their simple structures and low-cost fabrication processing, showing great potential for full-color displays and solid-state lighting. In this work, we rationally designed and synthesized two red-emitting cationic Ir(III) complexes, [Ir(tBuPBI)2(biq)]PF6 (R1) and [Ir(tBuPBI)2(qibi)]PF6 (R2), in which a tert-butyl-functionalized 1,2-diphenyl-1H-benzo[d]imidazole (PBI) unit and conjugated 2,2'-biquinoline (biq) and 2-(1-phenyl-1H-benzo[d]imidazol-2-yl)quinolone (qibi) were employed as cyclometalated and ancillary ligands, respectively. The introduced tert-butyl group led to homogeneous and highly emissive thin films by increasing the solubility and suppressing the strong intermolecular interactions due to steric hindrance. Based on the abovementioned high-quality emissive layer, high-efficiency LECs were achieved. An efficient red-emitting LEC fabricated on a glass substrate achieved a current efficiency (ηC) of 7.18 cd/A and an external quantum efficiency (ηext) of 9.32%. By doping both complexes into a blue-green-emitting cationic Ir(III) complex, high-performance white LECs were also successfully fabricated with Commission International de L'Eclairage (CIE) coordinates of (0.39,0.39), a ηC of 17.43 cd/A, and a ηext of 8.92%. In addition, we also fabricated flexible red and white LECs with outstanding efficiencies and mechanical flexibilities. The ηC and ηext values of a flexible white LEC could be as high as 13.50 cd/A and 6.86%, respectively. The efficiency of the flexible device remained at approximately 95% of the initial value after 500 bends with a radius of curvature of 5 mm, demonstrating the great potential of these complexes for full-color displays and flexible optoelectronics.
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Affiliation(s)
- Qunying Zeng
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Fushan Li
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Zhixin Chen
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Kaiyu Yang
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Yang Liu
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Tailiang Guo
- Institute of Optoelectronic Technology , Fuzhou University , Fuzhou 350002 , People's Republic of China
| | - Guo-Gang Shan
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery Faculty of Chemistry , Northeast Normal University , Changchun , Jilin 130024 , People's Republic of China
| | - Zhongmin Su
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery Faculty of Chemistry , Northeast Normal University , Changchun , Jilin 130024 , People's Republic of China
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22
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Li C, Dickson R, Rockstroh N, Rabeah J, Cordes DB, Slawin AMZ, Hünemörder P, Spannenberg A, Bühl M, Mejía E, Zysman-Colman E, Kamer PCJ. Ligand electronic fine-tuning and its repercussion on the photocatalytic activity and mechanistic pathways of the copper-photocatalysed aza-Henry reaction. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01221a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Subtle electronic ligand effects have a strong impact on the mechanistic pathway of a photocatalytic coupling reaction.
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Affiliation(s)
- Chenfei Li
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
| | - Robert Dickson
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
| | | | - Jabor Rabeah
- Leibniz Institute for Catalysis
- 18059 Rostock
- Germany
| | - David B. Cordes
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
| | - Alexandra M. Z. Slawin
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
| | | | | | - Michael Bühl
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
| | | | - Eli Zysman-Colman
- Organic Semiconductor Centre
- EaStCHEM School of Chemistry
- University of St Andrews
- KY16 9ST St Andrews
- UK
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23
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Rozhkov AV, Eliseeva SN, Baykov SV, Zelenkov LE, Goriachiy DO, Taydakov IV. Copper( i) ionic complexes based on imidazo[4,5- f][1,10]phenanthrolin diimine chelating ligands: crystal structures, and photo- and electroluminescence properties. NEW J CHEM 2020. [DOI: 10.1039/c9nj05109k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Four new luminescent diimine Cu(i) complexes have been synthesized and applied in organic light-emitting diodes.
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Affiliation(s)
- Anton V. Rozhkov
- Institute of Chemistry
- Saint Petersburg State University
- 199034 Saint Petersburg
- Russian Federation
| | - Svetlana N. Eliseeva
- Institute of Chemistry
- Saint Petersburg State University
- 199034 Saint Petersburg
- Russian Federation
| | - Sergey V. Baykov
- Institute of Chemistry
- Saint Petersburg State University
- 199034 Saint Petersburg
- Russian Federation
| | - Lev E. Zelenkov
- Institute of Chemistry
- Saint Petersburg State University
- 199034 Saint Petersburg
- Russian Federation
| | - Dmitry O. Goriachiy
- P. N. Lebedev Physical Institute of the Russian Academy of Science
- 119991 Moscow
- Russian Federation
| | - Ilya V. Taydakov
- P. N. Lebedev Physical Institute of the Russian Academy of Science
- 119991 Moscow
- Russian Federation
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24
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Keller S, Prescimone A, La Placa MG, Junquera-Hernández JM, Bolink HJ, Constable EC, Sessolo M, Ortí E, Housecroft CE. The shiny side of copper: bringing copper(i) light-emitting electrochemical cells closer to application. RSC Adv 2020; 10:22631-22644. [PMID: 35514545 PMCID: PMC9054616 DOI: 10.1039/d0ra03824e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 05/31/2020] [Indexed: 01/06/2023] Open
Abstract
Heteroleptic [Cu(P^P)(N^N)][PF6] complexes, where N^N is 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2bpy), 4,5,6-trimethyl-2,2′-bipyridine (4,5,6-Me3bpy), 6-(tert-butyl)-2,2′-bipyridine (6-tBubpy) and 2-ethyl-1,10-phenanthroline (2-Etphen) and P^P is either bis(2-(diphenylphosphino)phenyl)ether (POP, PIN [oxydi(2,1-phenylene)]bis(diphenylphosphane)) or 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos, PIN (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane)) have been synthesized and their NMR spectroscopic, mass spectrometric, structural, electrochemical and photophysical properties were investigated. The single-crystal structures of [Cu(POP)(5,5′-Me2bpy)][PF6], [Cu(xantphos)(5,5′-Me2bpy)][PF6], [Cu(POP)(6-tBubpy)][PF6], [Cu(POP)(4,5,6-Me3bpy)][PF6]·1.5Et2O, [Cu(xantphos)(4,5,6-Me3bpy)][PF6]·2.33CH2Cl2, [Cu(POP)(2-Etphen)][PF6] and [Cu(xantphos)(2-Etphen)][PF6] are described. While alkyl substituents in general exhibit electron-donating properties, variation in the nature and substitution-position of the alkyl group in the N^N chelate leads to different effects in the photophysical properties of the [Cu(P^P)(N^N)][PF6] complexes. In the solid state, the complexes are yellow to green emitters with emission maxima between 518 and 602 nm, and photoluminescence quantum yields (PLQYs) ranging from 1.1 to 58.8%. All complexes show thermally activated delayed fluorescence (TADF). The complexes were employed in the active layer of light-emitting electrochemical cells (LECs). The device performance properties are among the best reported for copper-based LECs, with maximum luminance values of up to 462 cd m−2 and device half-lifetimes of up to 98 hours. Heteroleptic copper(i) complexes with bisphosphanes and astutely tuned N^N chelating ligands as emitters give bright LECs with record-breaking stability.![]()
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Affiliation(s)
- Sarah Keller
- Department of Chemistry
- University of Basel
- CH-4058 Basel
- Switzerland
| | | | | | | | - Henk J. Bolink
- Instituto de Ciencia Molecular
- Universidad de Valencia
- 46980 Paterna
- Spain
| | | | - Michele Sessolo
- Instituto de Ciencia Molecular
- Universidad de Valencia
- 46980 Paterna
- Spain
| | - Enrique Ortí
- Instituto de Ciencia Molecular
- Universidad de Valencia
- 46980 Paterna
- Spain
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25
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Abstract
A series of [Cu(POP)(N^N][PF6] and [Cu(xantphos)(N^N][PF6] compounds has been prepared and characterized in which POP = bis[2-(diphenylphosphanyl)phenyl]ether (IUPAC PIN oxydi(2,1-phenylene)bis(diphenylphosphane), xantphos = 4,5-bis(diphenylphosphanyl)-9,9-dimethyl-9H-xanthene (IUPAC PIN (9,9-dimethyl-9H-xanthene- 4,5-diyl)bis(diphenylphosphane)) and the N^N ligands are 4-(4-bromophenyl)-6,6′-dimethyl-2,2′- bipyridine (1), 5,5′-bis(3-methoxyphenyl)-6-methyl-2,2′-bipyridine (2), and 6-benzyl-2,2′-bipyridine (3). The single crystal structures of [Cu(xantphos)(1)][PF6]·CH2Cl2, [Cu(xantphos)(2)][PF6]·CH2Cl2 and [Cu(POP)(3)][PF6]·0.5H2O were determined by X-ray diffraction. Each complex contains a copper(I) ion in a distorted tetrahedral environment with chelating N^N and P^P ligands. In the [Cu(xantphos)(1)]+ and [Cu(xantphos)(2)]+ cations, there are face-to-face π-stackings of bpy and PPh2 phenyl rings (i.e., between the ligands); in addition in [Cu(xantphos)(2)][PF6]·CH2Cl2, inter-cation π-embraces lead to the formation of infinite chains as a primary packing motif. In [Cu(POP)(3)][PF6]·0.5H2O, centrosymmetric pairs of [Cu(POP)(3)]+ cations engage in C–H…π (phenyl to bpy) and offset face-to-face (bpy…bpy) contacts. The electrochemical and photophysical properties of the compounds containing ligands 1 and 2 are reported. They are green or yellow emitters in the solid-state (λem in the range 535–577 nm) with values for the photoluminescence quantum yield (PLQY) in the range 19%–41%.
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26
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Zhang L, Zuo Q. A series of blue-green-yellow-red emitting Cu(I) complexes: Molecular structure and photophysical performance. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 223:117280. [PMID: 31234018 DOI: 10.1016/j.saa.2019.117280] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/14/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
In this work, we designed a series of [Cu(NN)(PPh3)2]BF4 complexes with different optical edge values and emission colors from blue to red, where NN and PPh3 denoted a diamine ligand and triphenylphosphine, respectively. Six NN ligands with various conjugation chains (short π chain, modest π chain and long π chain) were selected. A systematical comparison between these Cu(I) complexes was performed, so that the correlation between NN structure and [Cu(NN)(PPh3)2] photophysical performance was tentatively discussed. Their single crystal structure was found consistent with literature ones, forming a typical tetrahedral coordination geometry. Density functional theory calculation indicated that their onset electronic transition showed a mixed character of metal-to-ligand-charge-transfer and ligand-to-ligand-charge-transfer. Detailed analysis on photophysical parameters suggested that the absorption edge of [Cu(NN)(PPh3)2]BF4 complex was controlled by conjugation length in diamine ligand. A wide absorption edge needed a short conjugation chain in diamine ligand. Similar tendency was found for their emission spectra. In addition, a long conjugation chain in diamine ligand widened emission spectra obviously. Emission dynamics showed slim correlation with diamine ligand conjugation length since the excited state was controlled mainly by dynamic procedure and steric factor of diamine ligands.
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Affiliation(s)
- Liming Zhang
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, PR China.
| | - Qinghui Zuo
- School of Materials Science and Engineering, Changchun University of Science and Technology, No. 7989, Weixing Road, Changchun 130022, PR China.
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27
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Elistratova J, Faizullin B, Dayanova I, Strelnik I, Strelnik A, Gerasimova T, Fayzullin R, Babaev V, Khrizanforov M, Budnikova Y, Musina E, Katsyuba S, Karasik A, Mustafina A, Sinyashin O. Reversible temperature-responsible emission in solutions within 293–333 K produced by dissociative behavior of multinuclear Cu(I) complexes with aminomethylphosphines. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.119125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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28
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Keller S, Bantle M, Prescimone A, Constable EC, Housecroft CE. Hinged and Wide: A New P^P Ligand for Emissive [Cu(P^P)(N^N)][PF 6] Complexes. Molecules 2019; 24:E3934. [PMID: 31683579 PMCID: PMC6864541 DOI: 10.3390/molecules24213934] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 10/29/2019] [Accepted: 10/29/2019] [Indexed: 12/02/2022] Open
Abstract
Heteroleptic [Cu(BIPHEP)(N^N)][PF6] complexes (BIPHEP = 1,1'-biphenyl-2,2'-diylbis(diphenylphosphane)), in which N^N is 2,2'-bipyridine (bpy), 6-methyl-2,2'-bipyridine (6-Mebpy), 6-ethyl-2,2'-bipyridine (6-Etbpy), or 5,5'-dimethyl-2,2'-bipyridine (5,5'-Me2bpy), have been synthesized and characterized using multinuclear NMR spectroscopies and electrospray ionization mass spectrometry. The single crystal structures of [Cu(BIPHEP)(bpy)][PF6]∙CH2Cl2, [Cu(BIPHEP)(5,5'-Me2bpy)][PF6]∙CH2Cl2, [Cu(BIPHEP)(6-Mebpy)][PF6]∙Et2O∙0.5H2O and [Cu(BIPHEP)(6-Etbpy)][PF6] confirm distorted tetrahedral {Cu(P^P)(N^N)} coordination environments. Each compound shows a quasi-reversible Cu+/Cu2+ process. In deaerated solution, the compounds are weak emitters. Powdered samples are yellow emitters (λemmax in the range 558-583 nm) and [Cu(BIPHEP)(5,5'-Me2bpy)][PF6] exhibits the highest photoluminescence quantum yield (PLQY = 14%). On cooling to 77 K (frozen 2-methyloxolane), the emission maxima are red-shifted and the excited state lifetimes increase from τ1/2 < 8 μs, to τ1/2 values of up to 53 μs, consistent with the compounds with N^N = 6-Mebpy, 6-Etbpy and 5,5'-Me2bpy exhibiting thermally activated delayed fluorescence (TADF).
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Affiliation(s)
- Sarah Keller
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
- Chimie ParisTech, PSL University CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 11 rue Pierre et Marie Curie, F-75005 Paris, France.
| | - Matthias Bantle
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
| | - Edwin C Constable
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
| | - Catherine E Housecroft
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland.
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29
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Herr P, Glaser F, Büldt LA, Larsen CB, Wenger OS. Long-Lived, Strongly Emissive, and Highly Reducing Excited States in Mo(0) Complexes with Chelating Isocyanides. J Am Chem Soc 2019; 141:14394-14402. [PMID: 31464429 DOI: 10.1021/jacs.9b07373] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Newly discovered tris(diisocyanide)molybdenum(0) complexes are Earth-abundant isoelectronic analogues of the well-known class of [Ru(α-diimine)3]2+ compounds with long-lived 3MLCT (metal-to-ligand charge transfer) excited states that lead to rich photophysics and photochemistry. Depending on ligand design, luminescence quantum yields up to 0.20 and microsecond excited state lifetimes are achieved in solution at room temperature, both significantly better than those for [Ru(2,2'-bipyridine)3]2+. The excited Mo(0) complexes can induce chemical reactions that are thermodynamically too demanding for common precious metal-based photosensitizers, including the widely employed fac-[Ir(2-phenylpyridine)3] complex, as demonstrated on a series of light-driven aryl-aryl coupling reactions. The most robust Mo(0) complex exhibits stable photoluminescence and remains photoactive after continuous irradiation exceeding 2 months. Our comprehensive optical spectroscopic and photochemical study shows that Mo(0) complexes with diisocyanide chelate ligands constitute a new family of luminophores and photosensitizers, which is complementary to precious metal-based 4d6 and 5d6 complexes and represents an alternative to nonemissive Fe(II) compounds. This is relevant in the greater context of sustainable photophysics and photochemistry, as well as for possible applications in lighting, sensing, and catalysis.
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Affiliation(s)
- Patrick Herr
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Felix Glaser
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Laura A Büldt
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Christopher B Larsen
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Oliver S Wenger
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
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30
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Wang Z, Sun X, Xu C, Ji B. Synthesis, Structures, and Photophysical Properties of Novel Four-Coordinate Cu(I) Complexes Supported by Chelating N-Heterocyclic Carbene Ligands. Front Chem 2019; 7:422. [PMID: 31231640 PMCID: PMC6561309 DOI: 10.3389/fchem.2019.00422] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/21/2019] [Indexed: 01/09/2023] Open
Abstract
Luminescent Cu(I) complexes are promising emitting materials for electroluminescent devices due to their low cost and abundant resources, as well as high emission efficiency. It is well-known that N-heterocyclic carbenes (NHCs) are excellent ligands for transition metal complexes. To investigate the photophysical properties of Cu(I)-NHC complexes, a series of new mononuclear four-coordinate Cu(I) complexes supported by the diphosphine ligand bis[2-(diphenylphosphino)phenyl]ether (POP) and the NHC ligands, consisting of imidazolylidene and pyrimidine units, were synthesized and fully characterized. To tune the photophysical properties of these Cu(I)-NHC complexes, the NHC ligands were attached with electron-withdrawing/donating groups (fluorine, chlorine, methyl and methoxyl) at the pyrimidine unit. All of these Cu(I)-NHC complexes adopt the typical distorted tetrahedral configuration. The electron-donating groups can lead to shorter Cu–N bond distances and longer Cu–C bond distances compared to the electron-withdrawing groups. Theoretical calculation results show that the highest occupied molecular orbitals are mainly distributed on the Cu(I) ion, POP, and carbene unit, while the lowest unoccupied molecular orbitals are mostly located on the pyrimidine unit of NHC ligands. The lowest energy electronic transitions of these Cu(I)-NHC complexes are mainly the metal-to-ligand charge transfer transition and ligand-to-ligand charge transfer transition. These Cu(I)-NHC complexes in solid state show tunable emissions from 530 to 618 nm with efficiencies of 0.5–38.1% at room temperature. The photophysical behaviors of these complexes at 298 and 50 K match well with the thermally activated delayed fluorescence (TADF) characteristics.
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Affiliation(s)
- Zhiqiang Wang
- College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials, Luoyang Normal University, Luoyang, China
| | - Xiaojuan Sun
- College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials, Luoyang Normal University, Luoyang, China
| | - Chen Xu
- College of Food and Pharmacy, Luoyang Normal University, Luoyang, China
| | - Baoming Ji
- College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials, Luoyang Normal University, Luoyang, China
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31
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Abstract
We report the synthesis and characterization of [Cu(P^P)(N^S)][PF6] complexes with P^P = bis(2-(diphenylphosphino)phenyl) ether (POP) or 4,5-bis(diphenylphosphino)-9,9- dimethylxanthene (xantphos) and N^S = 2-(iso-propylthio)pyridine (iPrSpy) or 2-(tert-butylthio)pyridine (tBuSpy). The single crystal structures of [Cu(POP)(iPrSPy)][PF6] and [Cu(POP)(tBuSPy)][PF6] have been determined and confirm a distorted tetrahedral copper(I) centre and chelating P^P and N^S ligands in each complex. Variable temperature (VT) 1H and 31P{1H} NMR spectroscopy reveals dynamic behavior with motion of the POP backbone in [Cu(POP)(iPrSPy)][PF6] and [Cu(POP)(tBuSPy)][PF6] frozen out at 238 K. VT NMR spectroscopic data including EXSY peaks in the ROESY spectrum of [Cu(xantphos)(tBuSPy)][PF6] at 198 K reveal that two conformers exist in an approximate ratio of 5:1. Replacing bpy by the N^S ligands shifts the Cu+/Cu2+ oxidation to a higher potential. The copper(I) compounds are weak emitters in the solid state with PLQY values of <2%. These values are similar to those for [Cu(POP)(bpy)][PF6] and [Cu(xantphos)(bpy)][PF6] in the solid state.
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