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Ferraro V, Bizzarri C, Bräse S. Thermally Activated Delayed Fluorescence (TADF) Materials Based on Earth-Abundant Transition Metal Complexes: Synthesis, Design and Applications. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2404866. [PMID: 38984475 PMCID: PMC11426009 DOI: 10.1002/advs.202404866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 06/27/2024] [Indexed: 07/11/2024]
Abstract
Materials exhibiting thermally activated delayed fluorescence (TADF) based on transition metal complexes are currently gathering significant attention due to their technological potential. Their application extends beyond optoelectronics, in particular organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs), and include also photocatalysis, sensing, and X-ray scintillators. From the perspective of sustainability, earth-abundant metal centers are preferred to rarer second- and third-transition series elements, thus determining a reduction in costs and toxicity but without compromising the overall performances. This review offers an overview of earth-abundant transition metal complexes exhibiting TADF and their application as photoconversion materials. Particular attention is devoted to the types of ligands employed, helping in the design of novel systems with enhanced TADF properties.
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Affiliation(s)
- Valentina Ferraro
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Kaiserstrasse 12, 76131, Karlsruhe, Germany
| | - Claudia Bizzarri
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Kaiserstrasse 12, 76131, Karlsruhe, Germany
| | - Stefan Bräse
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Kaiserstrasse 12, 76131, Karlsruhe, Germany
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Kaiserstrasse 12, 76131, Karlsruhe, Germany
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2
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Tong KM, Toigo J, Patrick BO, Wolf MO. Rhenium(I) Complexes with Sulfur-Bridged Dipyridyl Ligands: Structural, Photophysical, and Computational Studies. Inorg Chem 2023; 62:13662-13671. [PMID: 37555810 DOI: 10.1021/acs.inorgchem.3c02124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
A series of six new rhenium(I) tricarbonyl complexes [Re(CO)3(N-N)Br] bearing sulfur-bridged dipyridyl (N-N) ligands with three different oxidation states (sulfide (S), sulfoxide (SO), and sulfone (SO2)) are described. Spectroscopic studies show that changing the oxidation state of the ligands influences the photophysical properties of the complexes, with complexes 3 and 6 containing the sulfone ligand exhibiting a lower energy MLCT absorption band tailing into the visible region. Solution-state emission measurements show that these complexes exhibit readily tunable emission energies from 480 to 610 nm, depending on the oxidation state of the sulfur bridge and the presence of substituents on the pyridyl rings. Solid-state emission measurements show that the emission is significantly red-shifted upon oxidation of the sulfur bridge to sulfone with enhanced photoluminescence quantum yield.
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Affiliation(s)
- Ka-Ming Tong
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Jessica Toigo
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Brian O Patrick
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Michael O Wolf
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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3
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Perspectives on the Structural Design and Luminescent Behavior of Liquid Crystalline Materials Based on Copper(I) Complexes. CHEMISTRY 2023. [DOI: 10.3390/chemistry5010046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023] Open
Abstract
This paper provides insight into the various studies that have been carried out to date on liquid crystalline materials based on copper(I) complexes. Although the study of copper(I) complexes with respect to their liquid crystalline property is quite limited, metallomesogens prepared with different structural components and ligands from groups such as azamacrocycles, alkythiolates, ethers, isocyanides, phenanthroline, Schiff bases, pyrazolates, phosphines, biquinolines, and benzoylthioureas are reported and summarized in this review. A special section is dedicated to the discussion of emission properties of copper(I) metallomesogens.
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4
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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: 64] [Impact Index Per Article: 32.0] [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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5
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Yuan J, Xu Z, Wolf MO. Sulfur-bridged chromophores for photofunctional materials: using sulfur oxidation state to tune electronic and structural properties. Chem Sci 2022; 13:5447-5464. [PMID: 35694344 PMCID: PMC9116371 DOI: 10.1039/d2sc01128j] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/09/2022] [Indexed: 01/22/2023] Open
Abstract
The use of a heteroatom, such as sulfur, as a linker or bridge, in π-conjugated materials has advantages over purely carbon-based ones due to the accessibility of higher oxidation states as a result of hypervalence. Materials containing a sulfide bridge (S) can be systemically oxidized into sulfoxides (SO) and sulfones (SO2), each of which can then influence how a material interacts with light, playing a large role in dictating the photophysical and sometimes photochemical properties. In this perspective, we summarize the progress that our group and others have made, showing how oxidation of a sulfur bridge in symmetric bichromophoric dimers and in diimine ligands can influence the excited state behavior in organic π-conjugated materials and metal complexes.
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Affiliation(s)
- Jennifer Yuan
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia V6T 1Z1 Canada
| | - Zhen Xu
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia V6T 1Z1 Canada
| | - Michael O Wolf
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia V6T 1Z1 Canada
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6
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Hu FZ, Zhang L, Jin GY, Sun ZZ, Wang G, Han HL, Li ZF, Yang YP, Jin QH, Zhang F. Synthesis, spectral properties and terahertz time domain spectroscopy of two copper(I) complexes based on bisphosphine and bisazo ligands. J COORD CHEM 2022. [DOI: 10.1080/00958972.2022.2070486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Fu-Zhen Hu
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Lan Zhang
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Guan-Yu Jin
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Zhen-Zhou Sun
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Guo Wang
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Hong-Liang Han
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Zhong-Feng Li
- Department of Chemistry, Capital Normal University, Beijing, China
| | - Yu-Ping Yang
- School of Science, Minzu University of China, Beijing, China
| | - Qiong-Hua Jin
- Department of Chemistry, Capital Normal University, Beijing, China
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, China
| | - Fan Zhang
- Department of Chemistry, Capital Normal University, Beijing, China
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7
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Moutier F, Schiller J, Lecourt C, Khalil AM, Delmas V, Calvez G, Costuas K, Lescop C. Impact of Intermolecular Non‐Covalent Interactions in a Cu
I
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Discrete Assembly: Conformers’ Geometries and Stimuli‐Sensitive Luminescence Properties. Chemistry 2022; 28:e202104497. [DOI: 10.1002/chem.202104497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Indexed: 11/10/2022]
Affiliation(s)
- Florent Moutier
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | - Jana Schiller
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | - Constance Lecourt
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | | | - Vincent Delmas
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | - Guillaume Calvez
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | - Karine Costuas
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
| | - Christophe Lescop
- Université Rennes INSA Rennes, CNRS, ISCR – UMR6226 35000 Rennes France
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8
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Mondal D, Sardar G, Kabra D, Balakrishna MS. 2,2'-Bipyridine derived doubly B ← N fused bisphosphine-chalcogenides, [C 5H 3N(BF 2){NCH 2P(E)Ph 2}] 2 (E = O, S, Se): tuning of structural features and photophysical studies. Dalton Trans 2022; 51:6884-6898. [PMID: 35441638 DOI: 10.1039/d2dt00287f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
2,2'-Bipyridine based bisphosphine [C5H3N{N(H)CH2PPh2}]2 (1) and its bischalcogenide derivatives [C5H3N{N(H)CH2P(E)Ph2}]2 (2, E = O; 3, E = S; 4, E = Se) were synthesized, and further reacted with BF3·Et2O/Et3N to form doubly B ← N fused compounds [C5H3N(BF2){NCH2P(E)Ph2}]2 (5, E = O; 6, E = S; 7, E = Se) in excellent yields. The influence of the PE bonds on the electronic properties of the doubly B ← N fused systems and their structural features were investigated in detail, supported by extensive experimental and computational studies. Compound 6 exhibited a very high quantum yield of ϕ = 0.56 in CH2Cl2, whereas compound 7 showed a least quantum yield of ϕ = 0.003 in acetonitrile. Density functional theory (DFT) calculations demonstrated that the LUMO/HOMO of compounds 5-7 mostly delocalized over the entire π-conjugated frameworks. The involvement of PE bonds in the HOMO energy level of these compounds follows the order: PO < PS < PSe. Time-correlated single photon counting (TCSPC) experiments of compounds 5-7 revealed the singlet lifetime of 4.26 ns for 6, followed by 4.03 ns for 5 and a lowest value of 2.18 ns (τ1) and 0.47 ns (τ2) with a double decay profile for 7. Our findings provide important strategies for the design of highly effective B ← N bridged compounds and tuning their photophysical properties by oxidizing phosphorus with different chalcogens. Compounds 5 and 6 have been employed as green emitters (λem = 515 nm) in fluorescent organic light-emitting diodes (OLEDs). For compound 5, doped into the poly(9-vinylcarbazole) (PVK) matrix with 5 wt% doping concentration, nearly 90 Cd m-2 luminance with 0.022% external quantum efficiency (EQE) was achieved. The best performance was observed for compound 6 doped into PVK by 1 wt% having a maximum luminance of 350 Cd m-2 and a similar EQE value.
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Affiliation(s)
- Dipanjan Mondal
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Gopa Sardar
- Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Dinesh Kabra
- Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Maravanji S Balakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
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9
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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: 41] [Impact Index Per Article: 20.5] [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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Tudor CA, Iliş M, Secu M, Ferbinteanu M, Cîrcu V. Luminescent heteroleptic copper(I) complexes with phosphine and N-benzoyl thiourea ligands: Synthesis, structure and emission properties. Polyhedron 2022. [DOI: 10.1016/j.poly.2021.115542] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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11
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Liu N, Liu L, Zhong XX, Li FB, Li FY, Qin HM. Ethynyl π-coordinated and non-coordinated mononuclear Cu( i) halide diphosphine complexes: synthesis and photophysical studies. NEW J CHEM 2022. [DOI: 10.1039/d1nj05578j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Complexes 4 and 5 emit yellow green delayed fluorescence and complexes 1–3 and 6 and 7 show yellow green to greenish yellow prompt fluorescence.
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Affiliation(s)
- Nian Liu
- Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Li Liu
- Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Xin-Xin Zhong
- Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Fa-Bao Li
- Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Feng-Yan Li
- Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun, 130024, P. R. China
| | - Hai-Mei Qin
- Department of Chemistry, Xiamen University, Xiamen 361005, P. R. China
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12
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Mahoro GU, Fresta E, Elie M, di Nasso D, Zhang Q, Lohier JF, Renaud JL, Linares M, Wannemacher R, Cabanillas-Gonzalez J, Costa RD, Gaillard S. Towards rainbow photo/electro-luminescence in copper(i) complexes with the versatile bridged bis-pyridyl ancillary ligand. Dalton Trans 2021; 50:11049-11060. [PMID: 34286773 DOI: 10.1039/d1dt01689j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis and characterization of a family of copper(i) complexes bearing a bridged bis-pyridyl ancillary ligand is reported, highlighting how the bridge nature impacts the photo- and electro-luminescent behaviours within the family. In particular, the phosphonium bridge led to copper(i) complexes featuring good electrochemical stability and high ionic conductivity, as well as a stark blue-to-orange luminescence shift compared to the others. This resulted in high performance light-emitting electrochemical cells reaching stabilities of 10 mJ at ca. 40 cd m-2 that are one order of magnitude higher than those of the other complexes. Overall, this work sheds light onto the crucial role of the bridge nature of the bis-pyridyl ancillary ligand on the photophysical features, film forming and, in turn, on the final device performances.
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Xu K, Chen BL, Yang F, Liu L, Zhong XX, Wang L, Zhu XJ, Li FB, Wong WY, Qin HM. Largely Color-Tuning Prompt and Delayed Fluorescence: Dinuclear Cu(I) Halide Complexes with tert-Amines and Phosphines. Inorg Chem 2021; 60:4841-4851. [PMID: 33711236 DOI: 10.1021/acs.inorgchem.0c03755] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Luminescent copper(I) halide complexes with bi- and tridentate rigid ligands have gained wide research interests. In this paper, six tetracoordinate dinuclear copper(I) halide complexes, Cu2X2(ppda)2 [ppda = 2-[2-(dimethylamino)phenyl(phenyl)phosphino]-N,N-dimethylaniline, X = I (1), Br (2), Cl (3)] and Cu2X2(pfda)2 [pfda = 2-[2-(dimethylamino)-4-(trifluoromethyl)phenyl(phenyl)phosphino]-N,N-dimethyl-5-trifluoromethylaniline, X = I (4), Br (5), Cl (6)], were successfully prepared and systematically characterized on their structures and photophysical properties. Complexes 1-5 have a centrosymmetric form with a planar Cu2X2 unit, and complex 6 has a mirror symmetry form with a butterfly-shaped Cu2X2. Solid complexes 1, 4, and 5 emit delayed fluorescence at room temperature, intense blue to greenish yellow (λmax = 443-570 nm) light, and their peak wavelengths are located at 443-570 nm with microsecond lifetimes (τ = 0.4-19.2 μs, ΦPL = 0.05-0.48). Complexes 2, 3, and 6 show prompt fluorescence, very weak yellowish green to yellow (λmax = 534-595 nm) emission with peak wavelengths at 534-595 nm, and lifetimes in nanoseconds (τ = 4.4-9.3 ns, ΦPL < 0.0001). (Metal + halide) to ligand and intraligand charge transitions are the main origin of the emission of the complexes. Solution-processed, complex-4-based nondoped and doped devices emit yellow green light with CIE coordinated at (0.41, 0.51), a maximum EQE up to 0.17%, and luminance reaching 75.52 cd/m2.
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Affiliation(s)
- Ke Xu
- Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Hubei University, Wuhan 430062, P.R. China
| | - Bu-Lin Chen
- Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Hubei University, Wuhan 430062, P.R. China
| | - Fei Yang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, P.R. China
| | - Li Liu
- Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Hubei University, Wuhan 430062, P.R. China
| | - Xin-Xin Zhong
- Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Hubei University, Wuhan 430062, P.R. China
| | - Lei Wang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, P.R. China
| | - Xun-Jin Zhu
- Department of Chemistry, Hong Kong Baptist University, Hong Kong, P.R. China
| | - Fa-Bao Li
- Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Hubei University, Wuhan 430062, P.R. China
| | - Wai-Yeung Wong
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Hai-Mei Qin
- Department of Chemistry, Xiamen University, Xiamen 361005, P.R. China
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Busch JM, Koshelev DS, Vashchenko AA, Fuhr O, Nieger M, Utochnikova VV, Bräse S. Various Structural Design Modifications: para-Substituted Diphenylphosphinopyridine Bridged Cu(I) Complexes in Organic Light-Emitting Diodes. Inorg Chem 2021; 60:2315-2332. [PMID: 33464050 DOI: 10.1021/acs.inorgchem.0c03187] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The well-known system of dinuclear Cu(I) complexes bridged by 2-(diphenylphosphino)pyridine (PyrPhos) derivatives Cu2X2L3 and Cu2X2LP2 (L = bridging ligand, P = ancillary ligand) goes along with endless variation options for tunability. In this work, the influence of substituents and modifications on the phosphine moiety of the NP-bridging ligand was investigated. In previous studies, the location of the lowest unoccupied molecular orbital (LUMO) of the copper complexes of the PyrPhos family was found to be located on the NP-bridging ligand and enabled color tuning in the whole visible spectrum. A multitude of dinuclear Cu(I) complexes based on the triple methylated 2-(bis(4-methylphenyl)phosphino)-4-methylpyridine (Cu-1b-H, Cu-1b-MeO, and Cu-1b-F) up to complexes bearing 2-(bis(4-fluorophenyl)phosphino)pyridine (Cu-6a-H) with electron-withdrawing fluorine atoms over many other variations on the NP-bridging ligands were synthesized. Almost all copper complexes were confirmed via single crystal X-ray diffraction analysis. Besides theoretical TDDFT-studies of the electronic properties and photophysical measurements, the majority of the phosphino-modified Cu(I) complexes was tested in solution-processed organic light-emitting diodes (OLEDs) with different heterostructure variations. The best results of the OLED devices were obtained with copper emitter Cu-1b-H in a stack architecture of ITO/PEDOT-PSS (50 nm)/poly-TPD (15 nm)/20 wt % Cu(I) emitter:CBP:TcTA(7:3) (45 nm)/TPBi (30 nm)/LiF(1 nm)/Al (>100 nm) with a high brightness of 5900 Cd/m2 and a good current efficiency of 3.79 Cd/A.
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Affiliation(s)
- Jasmin M Busch
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Karlsruhe, Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Daniil S Koshelev
- Faculty of Materials Science, M.V. Lomonosov Moscow State University, 1/73 Leninskye Gory, Moscow, 119991, Russia
| | | | - Olaf Fuhr
- Institute of Nanotechnology (INT) and Karlsruhe Nano-Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Martin Nieger
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014, Helsinki, Finland
| | | | - Stefan Bräse
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Karlsruhe, Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.,Institute of Biological and Chemical Systems - Functional Molecular Systems, IBCS-FMS, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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15
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Sun ZZ, Zhu N, Pan X, Wang G, Li ZF, Xin XL, Han HL, Feng YB, Jin QH, Yang YP, Yang W. A new application of terahertz time-domain absorption spectra in luminescent complexes: characterization of the C-Hπ weak interactions in Cu(I) complexes. Dalton Trans 2021; 50:10214-10224. [PMID: 34232237 DOI: 10.1039/d1dt01023a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Six Cu(i) complexes, [Cu(2,3-f)(bdppmapy)]BF4 (1), [Cu(2,3-f)(bdppmapy)]ClO4 (2), [Cu(2,3-f)(bdppmapy)]CF3SO3 (3), [Cu(imidazo[4,5-f])(bdppmapy)]BF4 (4), [Cu(imidazo[4,5-f])(bdppmapy)]ClO4 (5), and [Cu(imidazo[4,5-f])(bdppmapy)]CF3SO3·MeOH (6·MeOH) (bdppmapy = N,N-bis[(diphenylphosphino)methyl]-2-pyridinamine, 2,3-f = pyrazine[2,3-f][1,10]-phenanthroline, and imidazo[4,5-f] = 1H-imidazo[4,5-f][1,10]-phenanthroline), have been synthesized to explore the effects of counteranions on their crystal structures, photophysical properties, and terahertz (THz) spectra. Time-dependent density functional theory (TD-DFT) shows that the luminescence performance of these complexes is attributed to the metal-to-ligand charge transfer (MLCT) in combination with ligand-to-ligand charge transfer (LLCT). In complexes 1-3, the characteristic peak at 1.4 THz is mainly related to the C-Hπ interaction formed by the H atom on the 4#/5# position of 2,3-f and the benzene ring from the bdppmapy on the adjacent asymmetric unit. The common C-Hπ interaction enhances the rigidity of the structure and has non-negligible influence on the photoluminescence quantum yields (PLQYs): the stronger the C-Hπ interaction is, the higher the quantum yield (QY) is. In complexes 4-6, similar absorption peaks (1.10-1.30 THz) are mainly related to the C-Hπ interactions, and strong absorption peaks (1.50-1.90 THz) are affected by the typical hydrogen bonds N-HF/O and O-HO. These results show that some weak interactions can be characterized by THz time-domain spectroscopy (THz-TDS). So, the THz spectroscopy method would make it possible to tune some of the weak interactions in complex structures to regulate the luminescence of materials.
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Affiliation(s)
- Zhen-Zhou Sun
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Ning Zhu
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Xun Pan
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Guo Wang
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Zhong-Feng Li
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Xiu-Lan Xin
- School of Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Hong-Liang Han
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Yue-Bing Feng
- School of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, China
| | - Qiong-Hua Jin
- Department of Chemistry, Capital Normal University, Beijing 100048, China. and State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China
| | - Yu-Ping Yang
- School of Science, Minzu University of China, Beijing 100081, China
| | - Wei Yang
- Faculty of Food Science and Technology, Suzhou Polytechnical Institute of Agriculture, Suzhou 215008, P. R. China.
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16
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Zhang B, Zhang J, Sun A, Liu C, Gu M, Chen Y, Wei B, Du C. Efficiently luminescent mononuclear copper iodide complexes with sterically hindered iminephosphine chelating ligands. NEW J CHEM 2021. [DOI: 10.1039/d1nj00622c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cu(i) complexes realize high luminescence properties due to steric hindrances of the ligands and synergistic heavy atom (Cu and I) effects.
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Affiliation(s)
- Bin Zhang
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Jie Zhang
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Ahui Sun
- Microelectronic R&D Center
- School of Mechatronic Engineering and Automation
- Shanghai University
- Shanghai
- P. R. China
| | - Chunmei Liu
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Mengsi Gu
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Yahui Chen
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
| | - Bin Wei
- Microelectronic R&D Center
- School of Mechatronic Engineering and Automation
- Shanghai University
- Shanghai
- P. R. China
| | - Chenxia Du
- College of Chemistry
- Zhengzhou University
- Zhengzhou
- P. R. China
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17
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Pitchaimani J, Rajkumar STRJ, Mahalingam SM, Philip Anthony S, Moon D, Madhu V. Coordination diversity in transition metal complexes with 4-aminoantipyrine tethered bis(imino)pyridine ligand: structures, superoxide dismutase and anticancer properties. J COORD CHEM 2020. [DOI: 10.1080/00958972.2020.1853109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Jayaraman Pitchaimani
- Department of Applied Chemistry, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, India
| | | | - S. M. Mahalingam
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur, Kancheepuram, India
| | | | - Dohyun Moon
- Beamline Department, Pohang Accelerator Laboratory, Pohang, Gyeongbuk, Korea
| | - Vedichi Madhu
- Department of Applied Chemistry, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, India
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18
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Xu Z, Climent C, Brown CM, Hean D, Bardeen CJ, Casanova D, Wolf MO. Controlling ultralong room temperature phosphorescence in organic compounds with sulfur oxidation state. Chem Sci 2020; 12:188-195. [PMID: 34163589 PMCID: PMC8178747 DOI: 10.1039/d0sc04715e] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/13/2020] [Indexed: 12/24/2022] Open
Abstract
Sulfur oxidation state is used to tune organic room temperature phosphorescence (RTP) of symmetric sulfur-bridged carbazole dimers. The sulfide-bridged compound exhibits a factor of 3 enhancement of the phosphorescence efficiency, compared to the sulfoxide and sulfone-bridged analogs, despite sulfone bridges being commonly used in RTP materials. In order to investigate the origin of this enhancement, temperature dependent spectroscopy measurements and theoretical calculations are used. The RTP lifetimes are similar due to similar crystal packing modes. Computational studies reveal that the lone pairs on the sulfur atom have a profound impact on enhancing intersystem crossing rate through orbital mixing and screening, which we hypothesize is the dominant factor responsible for increasing the phosphorescence efficiency. The ability to tune the electronic state without altering crystal packing modes allows the isolation of these effects. This work provides a new perspective on the design principles of organic phosphorescent materials, going beyond the rules established for conjugated ketone/sulfone-based organic molecules.
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Affiliation(s)
- Zhen Xu
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver BC V6T 1Z1 Canada
| | - Clàudia Climent
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid E-28049 Madrid Spain
| | - Christopher M Brown
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver BC V6T 1Z1 Canada
| | - Duane Hean
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver BC V6T 1Z1 Canada
| | - Christopher J Bardeen
- Department of Chemistry, University of California Riverside 501 Big Springs Road Riverside California 92521 USA
| | - David Casanova
- Donostia International Physics Center (DIPC) Paseo Manuel de Lardizabal 4 20018 Donostia Euskadi Spain
- IKERBASQUE, Basque Foundation for Science 48013 Bilbao Euskadi Spain
| | - Michael O Wolf
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver BC V6T 1Z1 Canada
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19
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Brown CM, Auvray T, DeLuca EE, Ezhova MB, Hanan GS, Wolf MO. Controlling photocatalytic reduction of CO 2 in Ru(II)/Re(I) dyads via linker oxidation state. Chem Commun (Camb) 2020; 56:10750-10753. [PMID: 32789403 DOI: 10.1039/d0cc04597g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Electronic communication between the linked metal centers in Ru(ii)-Re(i) dyads is tuned using the oxidation state (S and SO2) of sulfur-bridged ligands. Higher catalytic activity is seen for the SO2-bridged dyad in the photocatalytic reduction of CO2.
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Affiliation(s)
- Christopher M Brown
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
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20
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Brandl T, Kerzig C, Le Pleux L, Prescimone A, Wenger OS, Mayor M. Improved Photostability of a Cu I Complex by Macrocyclization of the Phenanthroline Ligands. Chemistry 2020; 26:3119-3128. [PMID: 31794079 PMCID: PMC7079024 DOI: 10.1002/chem.201904754] [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: 10/18/2019] [Revised: 11/30/2019] [Indexed: 11/12/2022]
Abstract
The development of molecular materials for conversion of solar energy into electricity and fuels is one of the most active research areas, in which the light absorber plays a key role. While copper(I)‐bis(diimine) complexes [CuI(L)2]+ are considered as potent substitutes for [RuII(bpy)3]2+, they exhibit limited structural integrity as ligand loss by substitution can occur. In this article, we present a new concept to stabilize copper bis(phenanthroline) complexes by macrocyclization of the ligands which are preorganized around the CuI ion. Using oxidative Hay acetylene homocoupling conditions, several CuI complexes with varying bridge length were prepared and analyzed. Absorption and emission properties are assessed; rewardingly, the envisioned approach was successful since the flexible 1,4‐butadiyl‐bridged complex does show enhanced MLCT absorption and emission, as well as improved photostability upon irradiation with a blue LED compared to a reference complex.
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Affiliation(s)
- Thomas Brandl
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Christoph Kerzig
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Loïc Le Pleux
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Alessandro Prescimone
- 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
| | - Marcel Mayor
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.,Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021, Karlsruhe, Germany.,Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
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21
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Brown CM, Arsenault NE, Cross TNK, Hean D, Xu Z, Wolf MO. Structural, electrochemical and photophysical behavior of Ru( ii) complexes with large bite angle sulfur-bridged terpyridyl ligands. Inorg Chem Front 2020. [DOI: 10.1039/c9qi01009b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sulfur-bridged terpyridyl ligands expand the bite angles in Ru(ii) species leading to geometries very close to that of a “perfect” octahedron. Altering the donor strength of substituents results in systematic tuning of the redox properties.
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Affiliation(s)
| | | | | | - Duane Hean
- Department of Chemistry
- University of British Columbia
- Vancouver
- Canada
| | - Zhen Xu
- Department of Chemistry
- University of British Columbia
- Vancouver
- Canada
| | - Michael O. Wolf
- Department of Chemistry
- University of British Columbia
- Vancouver
- Canada
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22
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Evariste S, Khalil AM, Kerneis S, Xu C, Calvez G, Costuas K, Lescop C. Luminescent vapochromic single crystal to single crystal transition in one-dimensional coordination polymer featuring the first Cu(i) dimer bridged by an aqua ligand. Inorg Chem Front 2020. [DOI: 10.1039/d0qi00691b] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Vapochromic luminescence caused by included solvent mobility is observed in reversible single-crystal to single-crystal (SC–SC) transitions in a one-dimensional coordination polymer bearing the first reported water molecule bridging two Cu(i) ions.
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Affiliation(s)
- Sloane Evariste
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Ali Moustafa Khalil
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Sebastien Kerneis
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Chendong Xu
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Guillaume Calvez
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Karine Costuas
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
| | - Christophe Lescop
- Univ Rennes
- INSA Rennes
- CNRS
- ISCR (Institut des Sciences Chimiques de Rennes) – UMR 6226
- F-35000 Rennes
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23
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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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