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Shafikov MZ, Zaytsev AV, Kozhevnikov VN. Trinuclear Cyclometalated Iridium(III) Complex Exhibiting Intense Phosphorescence of an Unprecedented Rate. Inorg Chem 2024; 63:1317-1327. [PMID: 38154085 DOI: 10.1021/acs.inorgchem.3c03810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Herein, we present two novel cyclometalated Ir(III) complexes of dinuclear and trinuclear design, Ir2(dppm)3(acac)2 and Ir3(dppm)4(acac)3, respectively, where dppm is 4,6-di(4-tert-butylphenyl)pyrimidine ligand and acac is acetylacetonate ligand. In both cases, rac-diastereomers were isolated during the synthesis. The materials show intense phosphorescence of outstanding rates (kr = ΦPL/τ) with corresponding radiative decay times of only τr = 1/kr = 0.36 μs for dinuclear Ir2(dppm)3(acac)2 and still shorter τr = 0.30 μs for trinuclear Ir3(dppm)4(acac)3, as measured for doped polystyrene film samples under ambient temperature. Measured under cryogenic conditions, radiative decay times of the three T1 substates (I, III, and III) and substate energy separations are τI = 11.8 μs, τII = 7.1 μs, τIII = 0.06 μs, ΔE(II-I) = 7 cm-1, and ΔE(III-I) = 175 cm-1 for dinuclear Ir2(dppm)3(acac)2 and τI = 3.1 μs, τII = 3.5 μs, τIII = 0.03 μs, ΔE(II-I) ≈ 1 cm-1, and ΔE(III-I) = 180 cm-1 for trinuclear Ir3(dppm)4(acac)3. The determined T1 state ZFS values (ΔE(III-I)) are smaller compared to that of mononuclear analogue Ir(dppm)2(acac) (ZFS = 210-1 cm). Theoretical analysis suggests that the high phosphorescence rates in multinuclear materials can be associated with the increased number of singlet states lending oscillator strength to the T1 → S0 transition.
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Affiliation(s)
- Marsel Z Shafikov
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstrasse 31, Regensburg D-93053, Germany
| | - Andrey V Zaytsev
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K
| | - Valery N Kozhevnikov
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K
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2
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Neelambaran N, Shamjith S, Murali VP, Maiti KK, Joseph J. Exploring a Mitochondria Targeting, Dinuclear Cyclometalated Iridium (III) Complex for Image-Guided Photodynamic Therapy in Triple-Negative Breast Cancer Cells. ACS APPLIED BIO MATERIALS 2023; 6:5776-5788. [PMID: 38061031 DOI: 10.1021/acsabm.3c00883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Photodynamic therapy (PDT) has emerged as an efficient and noninvasive treatment approach utilizing laser-triggered photosensitizers for combating cancer. Within this rapidly advancing field, iridium-based photosensitizers with their dual functionality as both imaging probes and PDT agents exhibit a potential for precise and targeted therapeutic interventions. However, most reported classes of Ir(III)-based photosensitizers comprise mononuclear iridium(III), with very few examples of dinuclear systems. Exploring the full potential of iridium-based dinuclear systems for PDT applications remains a challenge. Herein, we report a dinuclear Ir(III) complex (IRDI) along with a structurally similar monomer complex (IRMO) having 2-(2,4-difluorophenyl)pyridine and 4'-methyl-2,2'-bipyridine ligands. The comparative investigation of the mononuclear and dinuclear Ir(III) complexes showed similar absorption profiles, but the dinuclear derivative IRDI exhibited a higher photoluminescence quantum yield (Φp) of 0.70 compared to that of IRMO (Φp = 0.47). Further, IRDI showed a higher singlet oxygen generation quantum yield (Φs) of 0.49 compared to IRMO (Φs = 0.28), signifying the enhanced potential of the dinuclear derivative for image-guided photodynamic therapy. In vitro assessments indicate that IRDI shows efficient cellular uptake and significant photocytotoxicity in the triple-negative breast cancer cell line MDA-MB-231. In addition, the presence of a dual positive charge on the dinuclear system facilitates the inherent mitochondria-targeting ability without the need for a specific targeting group. Subcellular singlet oxygen generation by IRDI was confirmed using Si-DMA, and light-activated cellular apoptosis via ROS-mediated PDT was verified through various live-dead assays performed in the presence and absence of the singlet oxygen scavenger NaN3. Further, the mechanism of cell death was elucidated by an annexin V-FITC/PI flow cytometric assay and by investigating the cytochrome c release from mitochondria using Western blot analysis. Thus, the dinuclear complex designed to enhance spin-orbit coupling with minimal excitonic coupling represents a promising strategy for efficient image-guided PDT using iridium complexes.
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Affiliation(s)
- Nishna Neelambaran
- Chemical Sciences & Technology Division (CSTD), CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Shanmughan Shamjith
- Chemical Sciences & Technology Division (CSTD), CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Vishnu Priya Murali
- Chemical Sciences & Technology Division (CSTD), CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Kaustabh Kumar Maiti
- Chemical Sciences & Technology Division (CSTD), CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Joshy Joseph
- Chemical Sciences & Technology Division (CSTD), CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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3
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Yang X, Waterhouse GIN, Lu S, Yu J. Recent advances in the design of afterglow materials: mechanisms, structural regulation strategies and applications. Chem Soc Rev 2023; 52:8005-8058. [PMID: 37880991 DOI: 10.1039/d2cs00993e] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Afterglow materials are attracting widespread attention owing to their distinctive and long-lived optical emission properties which create exciting opportunities in various fields. Recent research has led to the discovery of many new afterglow materials featuring high photoluminescence quantum yields (PLQY) and lifetimes of up to several hours under ambient conditions. Afterglow materials are typically categorized according to their luminescence mechanism, such as long-persistent luminescence (LPL), room temperature phosphorescence (RTP), or thermally activated delayed fluorescence (TADF). Through rational design and novel synthetic strategies to modulate spin-orbit coupling (SOC) and populate triplet exciton states (T1), luminophores with long lifetimes and bright afterglow characteristics can be realized. Initial research towards afterglow materials focused mainly on pure inorganic materials, many of which possessed inherent disadvantages such as metal toxicity or low energy emissions. In recent years, organic-inorganic hybrid afterglow materials (OIHAMs) have been developed with high PLQY and long lifetimes. These hybrid materials exploit the tunable structure and easy processing of organic molecules, as well as enhanced SOC and intersystem crossing (ISC) processes involving heavy atom dopants, to achieve excellent afterglow performance. In this review, we begin by briefly discussing the structure and composition of inorganic and organic-inorganic hybrid afterglow materials, including strategies for regulating their lifetime, PLQY and luminescence wavelength. The specific advantages of organic-inorganic hybrid afterglow materials, including low manufacturing costs, diverse molecular/electronic structures, tunable structures and optical properties, and compatibility with a variety of substrates, are emphasized. Subsequently, we discuss in detail the fundamental mechanisms used by afterglow materials, their classification, design principles, and end applications (including sensing, anticounterfeiting, and photoelectric devices, among others). Finally, existing challenges and promising future directions are discussed, laying a platform for the design of afterglow materials for specific applications.
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Affiliation(s)
- Xin Yang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, China.
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
- International Center of Future Science, Jilin University, Changchun 130012, China
| | | | - Siyu Lu
- Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
| | - Jihong Yu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, China.
- International Center of Future Science, Jilin University, Changchun 130012, China
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Jayabharathi J, Thanikachalam V, Thilagavathy S. Phosphorescent organic light-emitting devices: Iridium based emitter materials – An overview. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2023.215100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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5
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Zhang X, Tong W, Chen M, Xie J, Wang Y, Mo Z, Wu S, Niu Z, Li G. Synthesis, photophysical properties, and
DFT
calculation of yellow‐red phosphorescent iridium(
III
) complexes based on thiophen‐pyrimidine/pyridine derivatives. J CHIN CHEM SOC-TAIP 2022. [DOI: 10.1002/jccs.202200370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiao‐Bin Zhang
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Wan‐Yue Tong
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Meng‐Sen Chen
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Jian‐Li Xie
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Yi‐Tong Wang
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Zheng‐Rong Mo
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Shui‐Xing Wu
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
| | - Zhi‐Gang Niu
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
- Key Laboratory of Emergency and Trauma, Ministry of Education, College of Emergency and Trauma Hainan Medical University Haikou China
| | - Gao‐Nan Li
- College of Chemistry and Chemical Engineering Hainan Normal University Haikou China
- Key Laboratory of Emergency and Trauma, Ministry of Education, College of Emergency and Trauma Hainan Medical University Haikou China
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6
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Ge ZR, Tong X, Huang YC, Li WH, Li HY, Lu AD, Li TY. Highly Luminescent Dinuclear Iridium(III) Complexes Containing Phenanthroline-Based Neutral Ligands as Chemosensors for Cu 2+ Ion. Organometallics 2022. [DOI: 10.1021/acs.organomet.1c00617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ze-Rong Ge
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Xin Tong
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Yi-Chuan Huang
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Wen-Hao Li
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Hong-Yan Li
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Ai-Dang Lu
- School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China
| | - Tian-Yi Li
- School of Chemistry and Biological Engineering, Department of Physical Chemistry, University of Science and Technology Beijing, Beijing, 100083, China
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7
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Guo S, Lu Z, Lu Q, Yang Y, Jiang Z, Zeng Q, Zhou W, Gong Y, Liu YMY, Liang J. Solution-processed high-performance orange-red organic light-emitting diode (OLED) based on ionic phosphorescent iridium(III) complex. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2022.122333] [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]
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8
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Xiong W, He K, Zhang D, Yang J, Peng M, Niu Z, Li G, Zhu W. Synthesis and optoelectronic properties of a dinuclear iridium (III) complex containing a picolinic acid derivative by nonconjugated linkage with a D-A-D core. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2021.122202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Jayabharathi J, Thanikachalam V, Seransenguttuvan B, Anudeebhana J, Sivaraj S. Efficient Stable Green Hybrid Light-Emitting Devices Using Cathode Interlayer. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.1c04021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Balu Seransenguttuvan
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu India
| | | | - Sekar Sivaraj
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu India
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10
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Recent Progress in Near-Infrared Organic Electroluminescent Materials. Top Curr Chem (Cham) 2021; 380:6. [PMID: 34878603 DOI: 10.1007/s41061-021-00357-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/21/2021] [Indexed: 10/19/2022]
Abstract
Near-infrared (NIR) refers to the section of the spectrum from 650 to 2500 nm. NIR luminescent materials are widely employed in organic light-emitting diodes (OLEDs), fiber optic communication, sensing, biological detection, and medical imaging. This paper reviews organic NIR electroluminescent materials, including organic NIR electrofluorescent materials and organic NIR electrophosphorescent materials that have been investigated in the past 6 years. Small-molecule, polymer NIR fluorescent materials and platinum(II) and iridium(III) complex NIR phosphorescent materials are described, and the limitations of the development of NIR luminescent materials and future prospects are discussed.
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11
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Bezzubov S, Ermolov K, Gorbunov A, Kalle P, Lentin I, Latyshev G, Kovalev V, Vatsouro I. Inherently dinuclear iridium(III) meso architectures accessed by cyclometalation of calix[4]arene-based bis(aryltriazoles). Dalton Trans 2021; 50:16765-16769. [PMID: 34761791 DOI: 10.1039/d1dt03579g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Conventional cyclometalation of calix[4]arene bis(aryltriazoles) with iridium(III) chloride hydrate leads to unique meso architectures in which the Ir2Cl2 core is cross-bound by two (C^N)2 ligands, which allows further replacement of the chloride bridges with ancillary ligands while maintaining the dinuclear structures of the complexes having independent or coupled iridium pairs.
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Affiliation(s)
- Stanislav Bezzubov
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, 119991 Moscow, Russia.
| | - Kirill Ermolov
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
| | - Alexander Gorbunov
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
| | - Paulina Kalle
- Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, 119991 Moscow, Russia.
| | - Ivan Lentin
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
| | - Gennadij Latyshev
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
| | - Vladimir Kovalev
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
| | - Ivan Vatsouro
- Department of Chemistry M. V. Lomonosov Moscow State University, Lenin's Hills 1, 119991 Moscow, Russia.
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12
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Buil ML, Esteruelas MA, López AM. Recent Advances in Synthesis of Molecular Heteroleptic Osmium and Iridium Phosphorescent Emitters. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100663] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- María L. Buil
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) Centro de Innovación en Química Avanzada (ORFEO-CINQA) Universidad de Zaragoza-CSIC 50009 Zaragoza Spain
| | - Miguel A. Esteruelas
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) Centro de Innovación en Química Avanzada (ORFEO-CINQA) Universidad de Zaragoza-CSIC 50009 Zaragoza Spain
| | - Ana M. López
- Departamento de Química Inorgánica Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) Centro de Innovación en Química Avanzada (ORFEO-CINQA) Universidad de Zaragoza-CSIC 50009 Zaragoza Spain
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13
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Sun Y, Liu B, Guo Y, Chen X, Lee YT, Feng Z, Adachi C, Zhou G, Chen Z, Yang X. Developing Efficient Dinuclear Pt(II) Complexes Based on the Triphenylamine Core for High-Efficiency Solution-Processed OLEDs. ACS APPLIED MATERIALS & INTERFACES 2021; 13:36020-36032. [PMID: 34283914 DOI: 10.1021/acsami.1c06148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The various applications of dinuclear complexes have attracted increasing attention. However, the electroluminescence efficiencies of dinuclear Pt(II) complexes are far from satisfactory. Herein, based on the triphenylamine core, we develop four dinuclear Pt(II) complexes that cover the emission colors from yellow to red with high photoluminescence quantum efficiencies of up to 0.79 in doped films. The solid-state structure of PyDPt is revealed by the single-crystal X-ray diffraction investigation. Besides, solution-processed OLEDs have been fabricated with different electron transport materials. With higher electron mobility and excellent hole-blocking ability, 1,3,5-tri(m-pyridin-3-ylphenyl)benzene (TmPyPB) can help to realize good charge balance in related OLEDs. In addition, angle-dependent PL spectra reveal the preferentially horizontal orientation of these dinuclear Pt(II) complexes in doped CBP films, which benefits the outcoupling efficiencies. Therefore, the yellow OLED based on PyDPt shows unexpected high performance with a peak current efficiency of up to 78.7 cd/A and an external quantum efficiency of up to 22.4%, which is the highest EQE reported for OLEDs based on dinuclear Pt(II) complexes so far. This study demonstrates the great potential of developing dinuclear Pt(II) complexes for achieving excellent electroluminescence efficiencies.
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Affiliation(s)
- Yuanhui Sun
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Bochen Liu
- School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, P. R. China
| | - Yue Guo
- School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, P. R. China
| | - Xi Chen
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Yi-Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka 819-0395, Japan
| | - Zhao Feng
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, P. R. China
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka 819-0395, Japan
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka 819-0395, Japan
| | - Guijiang Zhou
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Zhao Chen
- School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, P. R. China
| | - Xiaolong Yang
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, P. R. China
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14
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Cheng W, Sheng R, Liu Y, Wang S, Chen P, Tong B. Dinuclear iridium complexes with non-conjugated ditopic bis-terdentate cyclometallating ligands and their electroluminescence properties. INORG CHEM COMMUN 2021. [DOI: 10.1016/j.inoche.2021.108667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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15
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Mauro M. Phosphorescent multinuclear complexes for optoelectronics: tuning of the excited-state dynamics. Chem Commun (Camb) 2021; 57:5857-5870. [PMID: 34075949 DOI: 10.1039/d1cc01077h] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Luminescent transition metal complexes have attracted a great deal of attention in the last two decades from both fundamental and application points of view. The majority of the investigated and most efficient systems consist of monometallic compounds with judiciously selected ligand sphere, providing excellent triplet emitters for both lab-scale and real-market light-emitting devices for display technologies. More recently, chemical architectures comprising multimetallic compounds have appeared as an emerging and valuable alternative. Herein, the most recent trends in the field are showcased in a systematic approach, where the different examples are classified by metal center and ligand(s) scaffold. Their optical and electroluminescence properties are presented and compared as well. Indeed, the multimetallic strategy has proven to be highly suitable for compounds emitting efficiently in the challenging red to near-infrared region, yielding metal-based emitters with improved optical properties in terms of enhanced emission efficiency, shortened excited-state lifetime, and faster radiative rate constant. Finally, the advantages and drawbacks of the multimetallic approach will be discussed.
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Affiliation(s)
- Matteo Mauro
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR7504 Université de Strasbourg & CNRS 23 rue du Loess, 67083 Strasbourg, France.
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16
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Mao MX, Li FL, Shen Y, Liu QM, Xing S, Luo XF, Tu ZL, Wu XJ, Zheng YX. Simple Synthesis of Red Iridium(III) Complexes with Sulfur-Contained Four-Membered Ancillary Ligands for OLEDs. Molecules 2021; 26:molecules26092599. [PMID: 33946904 PMCID: PMC8125720 DOI: 10.3390/molecules26092599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/24/2021] [Accepted: 04/27/2021] [Indexed: 11/16/2022] Open
Abstract
Phosphorescent iridium(III) complexes have been widely researched for the fabrication of efficient organic light-emitting diodes (OLEDs). In this work, three red Ir(III) complexes named Ir-1, Ir-2, and Ir-3, with Ir-S-C-S four-membered framework rings, were synthesized efficiently at room temperature within 5 min using sulfur-containing ancillary ligands with electron-donating groups of 9,10-dihydro-9,9-dimethylacridine, phenoxazine, and phenothiazine, respectively. Due to the same main ligand of 4-(4-(trifluoromethyl)phenyl)quinazoline, all Ir(III) complexes showed similar photoluminescence emissions at 622, 619, and 622 nm with phosphorescence quantum yields of 35.4%, 50.4%, and 52.8%, respectively. OLEDs employing these complexes as emitters with the structure of ITO (indium tin oxide)/HAT-CN (dipyra-zino[2,3-f,2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile, 5 nm)/TAPC (4,4'-cyclohexylidenebis[N,N-bis-(4-methylphenyl)aniline], 40 nm)/TCTA (4,4″,4″-tris(carbazol-9-yl)triphenylamine, 10 nm)/Ir(III) complex (10 wt%): 2,6DCzPPy (2,6-bis-(3-(carbazol-9-yl)phenyl)pyridine, 10 nm)/TmPyPB (1,3,5-tri(mpyrid-3-yl-phenyl)benzene, 50 nm)/LiF (1 nm)/Al (100 nm) achieved good performance. In particular, the device based on complex Ir-3 with the phenothiazine unit showed the best performance with a maximum brightness of 22,480 cd m-2, a maximum current efficiency of 23.71 cd A-1, and a maximum external quantum efficiency of 18.1%. The research results suggest the Ir(III) complexes with a four-membered ring Ir-S-C-S backbone provide ideas for the rapid preparation of Ir(III) complexes for OLEDs.
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Affiliation(s)
- Meng-Xi Mao
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Fang-Ling Li
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Yan Shen
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Qi-Ming Liu
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Shuai Xing
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Xu-Feng Luo
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Zhen-Long Tu
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - Xue-Jun Wu
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (M.-X.M.); (F.-L.L.); (Y.S.); (Q.-M.L.); (S.X.); (X.-F.L.); (Z.-L.T.); (X.-J.W.)
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
- Correspondence:
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17
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Wu ZG, Yang B, Qiu YC, Wang Y, Dai H, Zheng YX, Wang Y, Hu L, Pan Y. Design of pyridinylphosphinate-based blue iridium phosphors for high-efficiency organic light-emitting diodes. Dalton Trans 2021; 50:3887-3893. [PMID: 33634813 DOI: 10.1039/d0dt03981k] [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
At present, cyclometalated iridium (Ir)(iii) complexes are the most promising emitters for OLEDs. Contrary to well-developed Ir(iii)-based red and green phosphorescent complexes, the efficient blue emitters are limited and the performances of blue OLEDs are still not satisfactory. Inspired by this, we designed two novel blue Ir(iii) complexes employing 2-(2,4-difluoropyridyl)pyridine (dfpypy) and 2,6-difluoro-3-(pyridin-2-yl)benzonitrile (FCN) as the main ligands, respectively, and phenyl(pyridin-2-yl)phosphinate (ppp) as the ancillary ligand. The rational design of the molecular structure makes the two complexes achieve blue emission and possess good electron mobility simultaneously. The devices based on the Ir(iii) phosphors exhibited good electroluminescence performances with low turn-on voltages, a peak current efficiency of 24.51 cd A-1, a maximum external quantum efficiency of 12.4%, a peak power efficiency of 21.99 lm W-1 and low efficiency roll-off. These results provide an effective strategy for the future molecular design of blue Ir(iii) complexes with good electron transport property for OLEDs.
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Affiliation(s)
- Zheng-Guang Wu
- College of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China.
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18
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Shafikov MZ, Martinscroft R, Hodgson C, Hayer A, Auch A, Kozhevnikov VN. Non-Stereogenic Dinuclear Ir(III) Complex with a Molecular Rack Design to Afford Efficient Thermally Enhanced Red Emission. Inorg Chem 2021; 60:1780-1789. [DOI: 10.1021/acs.inorgchem.0c03251] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marsel Z. Shafikov
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstrasse 31, Regensburg 93053, Germany
- Ural Federal University, Mira 19, Ekaterinburg 620002, Russia
| | - Ross Martinscroft
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Craig Hodgson
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Anna Hayer
- Merck KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Armin Auch
- Merck KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Valery N. Kozhevnikov
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
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19
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Shafikov MZ, Zaytsev AV, Kozhevnikov VN. Halide-Enhanced Spin-Orbit Coupling and the Phosphorescence Rate in Ir(III) Complexes. Inorg Chem 2021; 60:642-650. [PMID: 33405901 DOI: 10.1021/acs.inorgchem.0c02469] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The spin-forbidden nature of phosphorescence in Ir(III) complexes is relaxed by the metal-induced effect of spin-orbit coupling (SOC). A further increase of the phosphorescence rate could potentially be achieved by introducing additional centers capable of further enhancing the SOC effect, such as metal-coordinated halides. Herein, we present a dinuclear Ir(III) complex Ir2I2 that contains two Ir(III)-iodide moieties. The complex shows intense phosphorescence with a quantum yield of ΦPL(300 K) = 90% and a submicrosecond decay time of only τ(300 K) = 0.34 μs, as measured under ambient temperature for the degassed toluene solution. These values correspond to a top value T1 → S0 phosphorescence rate of kr = 2.65 × 106 s-1. Investigations at cryogenic temperatures allowed us to determine the zero-field splitting (ZFS) of the emitting state T1 ZFS(III-I) = 170 cm-1 and unusually short individual decay times of T1 substates: τ(I) = 6.4 μs, τ(II) = 7.6 μs, and τ(III) = 0.05 μs. This indicates a strong SOC of state T1 with singlet states. Theoretical investigations suggest that the SOC of state T1 with singlets is also contributed by halides. Strongly contributing to the higher occupied molecular orbitals of the complex (e.g., HOMO, HOMO - 1, and so forth), iodides work as important SOC centers that operate in tandem with metals. The examples of Ir2I2 and of earlier reported analogous complex Ir2Cl2 reveal that the metal-coordinated halides can enhance the SOC of state T1 with singlets and, consequently, the phosphorescence rate. A comparative study of Ir2I2 and Ir2Cl2 shows that the share of halides in total contribution (halides plus metals) to the SOC of state T1 with singlets increases strongly upon exchange of chlorides for iodides. The exchange also led to the decrease in values of ZFS of the T1 state from ZFS(III-I) = 205 cm-1 for Ir2Cl2 to T1 ZFS(III-I) = 170 cm-1 for Ir2I2. This results in a more efficient thermal population of the fastest emitting T1 substate III, thus further enhancing the room-temperature phosphorescence rate.
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Affiliation(s)
- Marsel Z Shafikov
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstrasse 31, Regensburg D-93053, Germany.,Department for Technology of Organic Synthesis, Institute of Chemical Technology, Ural Federal University, Mira 19, Ekaterinburg 620002, Russia
| | - Andrey V Zaytsev
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K
| | - Valery N Kozhevnikov
- Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K
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20
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Thanikachalam V, Seransenguttuvan B, Jayabharathi J. Versatile Accumulated Surface Plasmon Resonance of Functionalized Nanosilver in Polymer Devices. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Balu Seransenguttuvan
- Department of Chemistry, Annamalai University, Annamalainagar 608002, Tamil Nadu, India
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21
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Hao Z, Zhang K, Chen K, Lu Z, Wang P, Zhu W, Liu Y. An Effective Approach to Obtain Near-Infrared Emission from Binuclear Platinum(II) Complexes Involving Thiophenpyridine-Isoquinoline Bridging Ligand in Solution-Processed OLEDs. Chem Asian J 2020; 15:3003-3012. [PMID: 32721097 DOI: 10.1002/asia.202000544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/28/2020] [Indexed: 11/08/2022]
Abstract
Bimetallic complexes have become an emerging hot topic in field of luminous applications in recent years. Unlike the traditional modification on a cyclometalated ligand, grafting an additional metal ion provides a novel approach to tune molecular conjugation as well as the spin orbital coupling (SOC). Herein, we demonstrate a new kind of binuclear platinum(II) complex Pt-3 that possesses an asymmetric thiophenpyridine-isoquinoline bridging ligand. Compared to its mononuclear analogues of Pt-1 and Pt-2, an extremely large redshift emission from 576 and 618 nm to 721 nm was observed in solution. Binding of two metal ions helps to enhance molecular planarity, extend conjugation and suppress excited state distortion. However, their quantum yields tend to remarkably decrease with increasing red-shift emission as following the "energy gap law". The relatively larger HOMO/LUMO separation that induced by the second platinum ion also decreases the oscillator strength at the lowest singlet state, and goes against the fast radiative decay process. Solution-processed organic light-emitting diodes (OLEDs) based on Pt-1, Pt-2 and Pt-3 achieved external quantum efficiencies (EQEs) and luminance/radiant emittance of 13.6% and 13640 cd/m2 , 3.5% and 3754 cd/m2 , 0.9% and 7981 mW/Sr/m2 with the corresponding electroluminescent (EL) emission peaked at 580 nm, 625 nm and 708 nm, respectively. This work emphasizes the complement argument of the commonly largely reported symmetric binuclear configurations, and provides a new view to photophysical mechanism and design strategies for bimetallic species.
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Affiliation(s)
- Zhaoran Hao
- College of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, China
| | - Kai Zhang
- School of Materials Science and Engineering, Jiangsu Collaboration Innovation, Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-, Converting Materials and Applications, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, China
| | - Kuan Chen
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry and State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065, China
| | - Zhiyun Lu
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry and State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065, China
| | - Pu Wang
- College of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, China
| | - Weiguo Zhu
- School of Materials Science and Engineering, Jiangsu Collaboration Innovation, Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-, Converting Materials and Applications, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, China
| | - Yu Liu
- School of Materials Science and Engineering, Jiangsu Collaboration Innovation, Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-, Converting Materials and Applications, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, China.,College of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, China
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22
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Bonfiglio A, Pallova L, César V, Gourlaouen C, Bellemin‐Laponnaz S, Daniel C, Polo F, Mauro M. Phosphorescent Cationic Heterodinuclear Ir
III
/M
I
Complexes (M=Cu
I
, Au
I
) with a Hybrid Janus‐Type N‐Heterocyclic Carbene Bridge. Chemistry 2020; 26:11751-11766. [DOI: 10.1002/chem.202002767] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/04/2020] [Indexed: 01/13/2023]
Affiliation(s)
- Anna Bonfiglio
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR7504 Université de Strasbourg, CNRS 23 rue du Loess 67000 Strasbourg France
| | - Lenka Pallova
- LCC-CNRS UPR8241 Université de Toulouse, CNRS 31077 Toulouse cedex 4 France
| | - Vincent César
- LCC-CNRS UPR8241 Université de Toulouse, CNRS 31077 Toulouse cedex 4 France
| | - Christophe Gourlaouen
- Laboratoire de Chimie Quantique Institut de Chimie de Strasbourg UMR7177 Université de Strasbourg-CNRS 4 Rue Blaise Pascal 67000 Strasbourg France
| | - Stéphane Bellemin‐Laponnaz
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR7504 Université de Strasbourg, CNRS 23 rue du Loess 67000 Strasbourg France
| | - Chantal Daniel
- Laboratoire de Chimie Quantique Institut de Chimie de Strasbourg UMR7177 Université de Strasbourg-CNRS 4 Rue Blaise Pascal 67000 Strasbourg France
| | - Federico Polo
- Department of Molecular Sciences and Nanosystems Ca' Foscari University of Venice Via Torino 155 30172 Venezia Italy
| | - Matteo Mauro
- Institut de Physique et Chimie des Matériaux de Strasbourg, UMR7504 Université de Strasbourg, CNRS 23 rue du Loess 67000 Strasbourg France
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23
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New yellow-emitting iridium(III) complexes containing 2-phenyl-2H-indazole-based ligands for high efficient OLEDs with EQE over 25%. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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24
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Hao Z, Zhang K, Chen K, Wang P, Lu Z, Zhu W, Liu Y. More efficient spin-orbit coupling: adjusting the ligand field strength to the second metal ion in asymmetric binuclear platinum(ii) configurations. Dalton Trans 2020; 49:8722-8733. [PMID: 32555914 DOI: 10.1039/d0dt00939c] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Two types of asymmetric binuclear platinum(ii) complexes (Pt-1 and Pt-3) bearing bridging ligands of 2-(2,4-difluorophenyl)-5-(pyridin-2-yl)pyridine and 2-(2,4-difluorophenyl)-4-(pyridin-2-yl)pyridine as well as their corresponding mononuclear counterparts (Pt-2, Pt-4, and Pt-5) were synthesized and characterized. Different chelating constructions of the second platinum(ii) ions and the bridging ligands in Pt-1 and Pt-3 gave rise to two kinds of electron-transition pathway during their photophysical processes. The meta-/para-carbon of nitrogen on the center pyridyl segments set different levels of ligand field strength to the second platinum(ii) ions, lowering their occupied d orbital to varying degrees. Pt-1 showed an enhanced spin-orbit coupling (SOC), caused by the additional metal component through direct orbital hybridization at higher states, where the fixed molecular skeleton induced by the additional metal-ligand bonding also helped to suppress molecular distortion in the excited state, ensuring a high quantum yield (Φ, 0.89 in toluene), which is among the best results in bimetallic complexes. While the second platinum(ii) ion in Pt-3 seemed to make no contribution to the radiative transition, and only contributed to the HOMO, it provided a benefit by enlarging the conjugate system. Solution-processed organic lighting emitting devices (OLEDs) fabricated with the bimetallic Pt-1 emitter achieved superior efficiencies and up to 21% external quantum efficiency (EQE) in the Kelly-green region.
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Affiliation(s)
- Zhaoran Hao
- College of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, China.
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25
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Feng S, Guo X, Zhang J. An effective strategy for simply varying relative position of two carbazole groups in the thermally activated delayed fluorescence emitters to achieve deep-blue emission. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 226:117564. [PMID: 31614274 DOI: 10.1016/j.saa.2019.117564] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/16/2019] [Accepted: 09/22/2019] [Indexed: 06/10/2023]
Abstract
The development of efficient deep-blue thermally activated delayed fluorescence (TADF) materials is especially important for organic light-emitting devices as displays and lighting sources. However, finding suitable deep-blue TADF emitters is still challenging. Based on an experimentally reported blue-light TADF emitter DCZ-TTR, two new molecules (DCZ1-TTR and DCZ2-TTR) have been designed to investigate the impact of the change of relative position in two carbazole groups on their TADF properties. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations coupled with the Marcus rate theory have been performed. It is found that the absorption and emission spectra simulated using the BMK functional can reproduce the available experimental data very well. The fluorescence emissions of DCZ1-TTR and DCZ2-TTR are predicted to show clear blue-shifting in cyclohexane with respect to their analogue DCZ-TTR. Especially, the emission wavelength of DCZ2-TTR is calculated to be 435nm, in the deep-blue light range. According to the Marcus rate theory, the rates of reverse intersystem crossing of DCZ1-TTR and DCZ2-TTR are estimated to be two orders of magnitude larger than that of DCZ-TTR, which is more favorable for the occurrence of delayed fluorescence. This strongly suggests that our newly designed two molecules DCZ1-TTR and DCZ2-TTR can be also expected to be potential blue-light or even deep-blue-light TADF emitters. This may be an effective strategy for realizing deep-blue emission by simply varying relative position of two carbazole groups in the TADF molecules. To our best knowledge, this is a novel finding, which may be useful in preparing highly efficient deep-blue TADF-OLED materials.
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Affiliation(s)
- Songyan Feng
- Institute of Upconversion Nanoscale Materials, Henan Provincial Engineering Research Center of Green Anticorrosion Technology for Magnesium Alloy, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, PR China
| | - Xugeng Guo
- Institute of Upconversion Nanoscale Materials, Henan Provincial Engineering Research Center of Green Anticorrosion Technology for Magnesium Alloy, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, PR China.
| | - Jinglai Zhang
- Institute of Upconversion Nanoscale Materials, Henan Provincial Engineering Research Center of Green Anticorrosion Technology for Magnesium Alloy, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, PR China.
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26
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Thanikachalam V, Seransenguttuvan B, Jayabharathi J. Efficient and chromaticity stable green and white organic light-emitting devices with organic–inorganic hybrid materials. RSC Adv 2020; 10:21206-21221. [PMID: 35518720 PMCID: PMC9054536 DOI: 10.1039/d0ra02122a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/21/2020] [Indexed: 11/26/2022] Open
Abstract
Efficient inverted bottom emissive organic light emitting diodes (IBOLEDs) with tin dioxide and/or Cd-doped SnO2 nanoparticles as an electron injection layer at the indium tin oxide cathode:electron transport layer interface have been fabricated. The SnO2 NPs promote electron injection efficiently because their conduction band (−3.6 eV) lies between the work function (Wf) of ITO (4.8 eV) and the LUMO of the electron-transporting molecule (−3.32 eV), leading to enhanced efficiency at low voltage. The 2.0% SnO2 NPs (25 nm) with Ir(ddsi)2(acac) emissive material (SnO2 NPs/ITO) have an enhanced current efficiency (ηc, cd A−1) of 52.3/24.3, power efficiency (ηp, lm W−1) of 10.9/3.4, external quantum efficiency (ηex, %) of 16.4/7.5 and luminance (L, cd m−2) of 28 182/1982. A device with a 2.0% Cd-doped SnO2 layer shows higher ηc (60.6 cd A−1), ηp (15.4 lm W−1), ηex (18.3%) and L (26 858 cd m−2) than SnO2 devices or control devices. White light emission was harvested from a mixture of Cd–SnO2 NPs and homoleptic blue phosphor Ir(tsi)3; the combination of blue emission (λEL = 428 nm) from Ir(tsi)3 and defect emission from Cd–SnO2 NPs (λEL = 568 nm) gives an intense white light with CIE of (0.31, 0.30) and CCT of 6961 K. The white light emission [CIE of (0.34, 0.35) and CCT of 5188 K] from colloid hybrid electrolyte BMIMBF4–SnO2 is also discussed. Efficient inverted bottom emissive organic light emitting diodes (IBOLEDs) with tin dioxide and/or Cd-doped SnO2 nanoparticles as an electron injection layer at the indium tin oxide cathode:electron transport layer interface have been fabricated.![]()
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27
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Li G, Zhu D, Wang X, Su Z, Bryce MR. Dinuclear metal complexes: multifunctional properties and applications. Chem Soc Rev 2020; 49:765-838. [DOI: 10.1039/c8cs00660a] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Dinuclear metal complexes have enabled breakthroughs in OLEDs, photocatalytic water splitting and CO2reduction, DSPEC, chemosensors, biosensors, PDT and smart materials.
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Affiliation(s)
- Guangfu Li
- Department of Chemistry
- Northeast Normal University
- Changchun
- P. R. China
| | - Dongxia Zhu
- Department of Chemistry
- Northeast Normal University
- Changchun
- P. R. China
| | - Xinlong Wang
- Department of Chemistry
- Northeast Normal University
- Changchun
- P. R. China
| | - Zhongmin Su
- Department of Chemistry
- Northeast Normal University
- Changchun
- P. R. China
- School of Chemistry and Environmental Engineering
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28
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Proximity effects on the phosphorescent properties of dinuclear salicylaldiminato cyclometalated iridium(III) complexes linked with polymethylene spacers. TRANSIT METAL CHEM 2019. [DOI: 10.1007/s11243-019-00368-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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Adeloye AO. Exploration of the Structural and Photophysical Characteristics of Mono- and Binuclear Ir(III) Cyclometalated Complexes for Optoelectronic Applications. MATERIALS 2019; 12:ma12172734. [PMID: 31454975 PMCID: PMC6747829 DOI: 10.3390/ma12172734] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/15/2019] [Accepted: 07/29/2019] [Indexed: 11/29/2022]
Abstract
Intrinsic characteristics possessed and exhibited by Ir(III) cyclometalated complexes need to be further examined, understood, and explored for greater value enhancement and potentiation. This work focuses primarily on the comparative studies of the ligand structures, types, and their substituent influence on the photophysical and optoelectronic properties of typical cyclometalated mono- and binuclear iridium(III) complexes in solution or solid states.
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Affiliation(s)
- Adewale Olufunsho Adeloye
- Ibrahim Shehu Shema Centre for Renewable Energy and Research (ISSCeRER), Umaru Musa Yar'adua University, Dutsinma Road, P.M.B. 2218 Katsina, Nigeria.
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30
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Lu GZ, Zhu Q, Liu L, Wu ZG, Zheng YX, Zhou L, Zuo JL, Zhang H. Pure Red Iridium(III) Complexes Possessing Good Electron Mobility with 1,5-Naphthyridin-4-ol Derivatives for High-Performance OLEDs with an EQE over 31. ACS APPLIED MATERIALS & INTERFACES 2019; 11:20192-20199. [PMID: 31070035 DOI: 10.1021/acsami.9b02558] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Three iridium(III) complexes (Ir(4tfmpq)2mND, Ir(4tfmpq)2mmND, and Ir(4tfmpq)2mpND) with the 4-(4-(trifluoromethyl)phenyl)quinazoline (4tfmpq) main ligand and 1,5-naphthyridin-4-ol derivatives (mND: 8-methyl-1,5-naphthyridin-4-ol, mmND: 2,8-dimethyl-1,5-naphthyridin-4-ol, mpND: 8-methyl-2-phenyl-1,5-naphthyridin-4-ol) as ancillary ligands were studied. The complexes (Ir(4tfmpq)2mND, Ir(4tfmpq)2mmND, and Ir(4tfmpq)2mpND) emit pure red emissions of 626-630 nm with high photoluminescence quantum yields of 85.2-93.4% in CH2Cl2 and better electron mobilities than that of tri(8-hydroxyquinoline)aluminum. By employing three pure red emitters, all the phosphorescent organic light-emitting diodes exhibited superior performances with a maximum external quantum efficiency of 31.48% and the efficiency roll-off is very mild, which are among the best results ever reported for pure red organic light-emitting diodes using Ir(III) complexes. In addition, CIE( x, y) coordinates of (0.670, 0.327) are also close to the standard red emission required by the National Television System Committee.
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Affiliation(s)
- Guang-Zhao Lu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China
| | - Qi Zhu
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China
| | - Liang Liu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China
| | - Zheng-Guang Wu
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China
| | - Liang Zhou
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China
| | - Jing-Lin Zuo
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China
| | - Hongjie Zhang
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China
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Tagare J, Dubey DK, Jou J, Vaidyanathan S. Near UV/Deep‐Blue Phenanthroimidazole‐Based Luminophores for Organic Light‐Emitting Diodes: Experimental and Theoretical Investigation. ChemistrySelect 2019. [DOI: 10.1002/slct.201900383] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jairam Tagare
- Optoelectronics laboratoryDepartment of ChemistryNational Institute of Technology Rourkela India
| | - Deepak Kumar Dubey
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu Taiwan- 30013
| | - Jwo‐Huei Jou
- Department of Materials Science and EngineeringNational Tsing Hua University Hsinchu Taiwan- 30013
| | - Sivakumar Vaidyanathan
- Optoelectronics laboratoryDepartment of ChemistryNational Institute of Technology Rourkela India
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32
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Su N, Zheng YX. Four-membered red iridium(iii) complexes with Ir-S-P-S structures: rapid room-temperature synthesis and application in OLEDs. Dalton Trans 2019; 48:7583-7588. [PMID: 31066420 DOI: 10.1039/c9dt01270b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, with sulfur-containing ancillary ligands of triethylamine salts of bis(4-methoxyphenyl)-phosphinodithioic acid (omess) and bis(3,5-di-tert-butyl-4-methoxyphenyl)phosphinodithioic acid (tbuss), two four-membered red iridium(iii) complexes (tfmpqz)2Ir(omess) and (tfmpqz)2Ir(tbuss) with Ir-S-P-S structures were synthesized rapidly at room temperature within 5 min, in which 4-(4-(trifluoromethyl)phenyl)quinazoline (tfmpqz) was used as the main ligand. The calculated Gibbs free energy changes of the complex formation reactions prove that they are exothermic and thermodynamically beneficial processes. Both Ir(iii) complexes show almost the same PL emissions at 624 and 623 nm with high phosphorescence quantum yields of 0.60 and 0.72, respectively. Using the two complexes as emitters, both organic light-emitting devices (OLEDs) with the structure of ITO/HATCN (hexaazatriphenylenehexacabonitrile, 5 nm)/TAPC ((bis(4-(N,N-ditolylamino)phenyl)cyclohexane, 30 nm)/(tfmpqz)2Ir(omess) or (tfmpqz)2Ir(tbuss):26DCzppy (2,6-bis-(3-(carbazol-9-yl)phenyl)pyridine) (12 wt%, 10 nm)/TmPyPB (1,3,5-tri((3-pyridyl)-phen-3-yl)benzene, 30 nm)/LiF (1 nm)/Al (100 nm) achieve good performances. Particularly, due to the introduction of tert-butyl groups into the (tfmpqz)2Ir(tbuss) complex, its device exhibits better device properties with a maximum luminance of 26 184 cd m-2, maximum current efficiency of 30.24 cd A-1, maximum power efficiency of 22.61 lm W-1 and maximum external quantum efficiency of 21.50% with CIE coordinates at (0.65, 0.34).
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Affiliation(s)
- Ning Su
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China.
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Lu GZ, Su N, Yang HQ, Zhu Q, Zhang WW, Zheng YX, Zhou L, Zuo JL, Chen ZX, Zhang HJ. Rapid room temperature synthesis of red iridium(iii) complexes containing a four-membered Ir-S-C-S chelating ring for highly efficient OLEDs with EQE over 30. Chem Sci 2019; 10:3535-3542. [PMID: 30996945 PMCID: PMC6432389 DOI: 10.1039/c8sc05605f] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 02/09/2019] [Indexed: 12/12/2022] Open
Abstract
Three red cyclometalated iridium(iii) complexes (4tfmpq)2Ir(dipdtc), (4tfmpq)2Ir(dpdtc) and (4tfmpq)2Ir(Czdtc) (4tfmpq = 4-(4-(trifluoromethyl)phenyl)quinazoline, dipdtc = N,N-diisopropyl dithiocarbamate, dpdtc = N,N-diphenyl dithiocarbamate, and Czdtc = N-carbazolyl dithiocarbamate) containing the unique four-membered Ir-S-C-S backbone ring were synthesized in five minutes at room temperature with good yields, and the Gibbs free energy calculation results indicate that all reactions are exothermic and thermodynamically favorable processes. The emission colors (λ peak = 641-611 nm), photoluminescence quantum efficiencies (Φ P = 58.3-93.0%) and bipolar properties can be effectively regulated by introducing different electron-donating substituents into the dithiocarbamate ancillary ligands. Employing these emitters, organic light emitting diodes (OLEDs) with double emissive layers exhibit excellent performances with a maximum brightness over 60 000 cd m-2, a maximum current efficiency of 40.68 cd A-1, a maximum external quantum efficiency (EQEmax) of 30.54%, and an EQE of 26.79% at the practical luminance of 1000 cd m-2. These results demonstrate that Ir(iii) complexes with sulfur-containing ligands can be rapidly synthesized at room temperature, which is key to the production of metal luminescent materials for large-scale application in highly efficient OLEDs.
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Affiliation(s)
- Guang-Zhao Lu
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Ning Su
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Hui-Qing Yang
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Qi Zhu
- State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China .
| | - Wen-Wei Zhang
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Liang Zhou
- State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China .
| | - Jing-Lin Zuo
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Zhao-Xu Chen
- State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210093 , P. R. China . ; ;
| | - Hong-Jie Zhang
- State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , P. R. China .
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Yang X, Li M, Peng H, Zhang Q, Wu S, Xiao W, Chen X, Niu Z, Chen G, Li G. Highly Luminescent Mono‐ and Dinuclear Cationic Iridium(III) Complexes Containing Phenanthroline‐Based Ancillary Ligand. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801367] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Xiao‐Han Yang
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Min Li
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Hui Peng
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Qian Zhang
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Shui‐Xing Wu
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Wan‐Qing Xiao
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Xing‐Liang Chen
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
| | - Zhi‐Gang Niu
- Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education Hainan Normal University 571158 Haikou China
| | - Guang‐Ying Chen
- Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education Hainan Normal University 571158 Haikou China
| | - Gao‐Nan Li
- Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province College of Chemistry and Chemical Engineering Hainan Normal University 571158 Haikou China
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35
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Feng Z, Sun Y, Yang X, Zhou G. Novel Emission Color‐Tuning Strategies in Heteroleptic Phosphorescent Ir(III) and Pt(II) Complexes. CHEM REC 2019; 19:1710-1728. [DOI: 10.1002/tcr.201800183] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 12/09/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Zhao Feng
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Department of Chemistry, School of Science, State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong University Xi'an 710049 P. R. China
| | - Yuanhui Sun
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Department of Chemistry, School of Science, State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong University Xi'an 710049 P. R. China
| | - Xiaolong Yang
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Department of Chemistry, School of Science, State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong University Xi'an 710049 P. R. China
| | - Guijiang Zhou
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Department of Chemistry, School of Science, State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong University Xi'an 710049 P. R. China
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36
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Zhang L, Yan ZP, Zheng YX. Efficient sky-blue OLEDs with extremely low efficiency roll-off based on stable iridium complexes with a bis(diphenylphorothioyl)amide ligand. Dalton Trans 2019; 48:9744-9750. [PMID: 30984967 DOI: 10.1039/c9dt00298g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The lack of efficient blue-emitting materials is one of the most important issues faced when extending the application of organic light-emitting diodes (OLEDs). Therefore, in this study, the ancillary ligand bis(diphenylphorothioyl)amide (Stpip) was utilized in iridium(iii) complexes with 2-(2,4-difluorophenyl)pyridine (dfppy) and 2-(2,4-difluorophenyl)pyrimidine (dfppm) as the main ligands, respectively. The two complexes, (dfppy)2Ir(Stpip) and (dfppm)2Ir(Stpip), exhibit sky-blue emission peaks at 466 and 474 nm with photoluminescence quantum yields of 12% and 89%, respectively. Due to the strong coordination capability between sulfur and iridium atoms, both complexes can be prepared with extremely high production yields under mild conditions. Furthermore, a double light-emitting layer device using (dfppm)2Ir(Stpip) as the emitter exhibits a maximum external quantum efficiency (EQEmax) of 19.4% with Commission Internationale de l'Eclairage (CIE) coordinates of (0.13, 0.27). Specifically, the EQE remains at 19.2% at a practical brightness of 1000 cd m-2, indicating an inappreciable efficiency roll-off.
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Affiliation(s)
- Lin Zhang
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China.
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37
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Su N, Yang HQ, Zheng YX, Chen ZX. Sulfur atom containing ligands induced rapid room temperature synthesis of red iridium(iii) complexes with Ir–S–P–S structures for OLEDs. NEW J CHEM 2019. [DOI: 10.1039/c9nj01599j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two red iridium(iii) complexes containing a four-membered ring Ir–S–P–S backbone were synthesized at room temperature in 5 min, and their OLEDs exhibit an EQEmax of 19.90%.
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Affiliation(s)
- Ning Su
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Hui-Qing Yang
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Zhao-Xu Chen
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
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38
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Zhang QC, Xiao H, Zhang X, Xu LJ, Chen ZN. Luminescent oligonuclear metal complexes and the use in organic light-emitting diodes. Coord Chem Rev 2019. [DOI: 10.1016/j.ccr.2018.01.017] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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39
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Jayabharathi J, Thanikachalam V, Ramya R, Panimozhi S. Strategic tuning of excited-state properties of electroluminescent materials with enhanced hot exciton mixing. RSC Adv 2019; 9:33693-33709. [PMID: 35528924 PMCID: PMC9073535 DOI: 10.1039/c9ra07509g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 10/14/2019] [Indexed: 12/30/2022] Open
Abstract
Deep blue emitters with excellent stability, high quantum yield and multifunctionality are the major issues for full-color displays. In line with this, new multifunctional, thermally stable blue emitters viz., N-(4-(10-(1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-1H-phenanthro[9,10-d]imidazol-2-yl)anthracen-9-yl)phenyl)-N-phenylbenzenamine (DPIAPPB) and 2-(10-(9H-carbazol-9-yl)anthracen-9-yl)-1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-1H-phenanthro[9,10-d]imidazole (CADPPI) with hybridized local charge transfer state (HLCT) and hot exciton properties have been synthesized. These molecules show high photoluminescence quantum yield (Φs/f): (DPIAPPB – 0.82/0.70 and CADPPI – 0.91/0.83). The CADPPI based device (EL – 467 nm) shows high efficiencies [ηc – 9.85 cd A−1; ηp – 10.84 lm W−1; ηex – 4.78% at 2.8 V; CIE (0.15, 0.10)] compared to the DPIAPPB device (EL − 472 nm) [ηc – 6.56 cd A−1; ηp – 6.16 lm W−1; ηex – 4.15% at 2.8 V with CIE (0.15, 0.12)]. The green device with CADPPI:Ir(ppy)3 exhibits a maximum L – 59 012 cd m−2; ηex – 16.8%; ηc – 37.3 cd A−1; ηp – 39.8 lm W−1 with CIE (0.30, 0.60) and the red device with CADPPI:Ir(MDQ)2(acac) shows a maximum L – 43 456 cd m−2; ηex – 21.9%; ηc – 36.0 cd A−1; ηp – 39.6 lm W−1 with CIE (0.64, 0.35). The CADPPI:Ir(ppy)3 device exhibits L – 90 12 cd m−2; ηex – 18.8%; ηc − 27.3 cd A−1; ηp – 29.8 lm W−1; CIE (0.30, 0.60).![]()
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40
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Stoliaroff A, Rio J, Latouche C. Accurate computations to simulate the phosphorescence spectra of large transition complexes: simulated colors match experiment. NEW J CHEM 2019. [DOI: 10.1039/c9nj02388g] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, an ab initio investigation on the luminescence properties of three iridium(iii) complexes is reported.
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Affiliation(s)
- Adrien Stoliaroff
- Institut des Materiaux Jean Rouxel (IMN)
- Université de Nantes
- CNRS
- 44322 Nantes cedex 3
- France
| | - Jérémy Rio
- Institut des Materiaux Jean Rouxel (IMN)
- Université de Nantes
- CNRS
- 44322 Nantes cedex 3
- France
| | - Camille Latouche
- Institut des Materiaux Jean Rouxel (IMN)
- Université de Nantes
- CNRS
- 44322 Nantes cedex 3
- France
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41
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Yan ZP, Liao K, Han HB, Su J, Zheng YX, Zuo JL. Chiral iridium(iii) complexes with four-membered Ir–S–P–S chelating rings for high-performance circularly polarized OLEDs. Chem Commun (Camb) 2019; 55:8215-8218. [DOI: 10.1039/c9cc03915e] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
CP-OLEDs with two series of chiral iridium(iii) complexes based on four-membered Ir–S–P–S chelating rings and chiral BINOL-based derivatives show excellent electroluminescence performances with obvious CPEL properties.
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Affiliation(s)
- Zhi-Ping Yan
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Kang Liao
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Hua-Bo Han
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Jian Su
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
| | - Jing-Lin Zuo
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
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42
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Photoluminescence and electroluminescence of four orange-red and red organic iridium(III) complexes. J Organomet Chem 2018. [DOI: 10.1016/j.jorganchem.2018.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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43
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Li TY, Wu J, Wu ZG, Zheng YX, Zuo JL, Pan Y. Rational design of phosphorescent iridium(III) complexes for emission color tunability and their applications in OLEDs. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.06.014] [Citation(s) in RCA: 163] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Wang Y, Bai K, Wang S, Ding J, Wang L. Tetranuclear Iridium Complex with a Self-Host Feature for High-Efficiency Nondoped Phosphorescent Organic Light-Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2018; 10:32365-32372. [PMID: 30179454 DOI: 10.1021/acsami.8b06750] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A tetranuclear Ir complex 3IrB-IrG was newly designed and synthesized with one green-emitting complex as the core, whose periphery is encapsulated by three blue-emitting complexes via a nonconjugated linkage. In the case of such a multinuclear system, a self-host feature can be formed, showing negligible electron communication, efficient outside-in energy transfer, and unique shielding effect. When using 3IrB-IrG as the emitting layer in the absence of host, the corresponding nondoped device reveals a state-of-art luminous efficiency of 32.6 cd/A (34.2 lm/W, 9.7%) as well as CIE coordinates of (0.38, 0.58). The performance significantly outperforms that of the bare mononuclear complex IrG (8.4 cd/A, 9.2 lm/W, 2.5%), highlighting the potential of self-host multinuclear complexes to realize high-efficiency nondoped PhOLEDs for the first time.
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Affiliation(s)
- Yang Wang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of the Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Keyan Bai
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of the Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Shumeng Wang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
| | - Junqiao Ding
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Lixiang Wang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of Science and Technology of China , Hefei 230026 , P. R. China
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Congrave DG, Batsanov AS, Du M, Liu Y, Zhu D, Bryce MR. Intramolecular π–π Interactions with a Chiral Auxiliary Ligand Control Diastereoselectivity in a Cyclometalated Ir(III) Complex. Inorg Chem 2018; 57:12836-12849. [DOI: 10.1021/acs.inorgchem.8b02034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel G. Congrave
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Andrei S. Batsanov
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Mingxu Du
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People’s Republic of China
| | - Yu Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People’s Republic of China
| | - Dongxia Zhu
- Key Laboratory of Nanobiosensing and Nanobioanalysis at Universities of Jilin Province, Department of Chemistry, Northeast Normal University, 5268 Renmin Street, Changchun, Jilin 130024, People’s Republic of China
| | - Martin R. Bryce
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
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Yang X, Jiao B, Dang JS, Sun Y, Wu Y, Zhou G, Wong WY. Achieving High-Performance Solution-Processed Orange OLEDs with the Phosphorescent Cyclometalated Trinuclear Pt(II) Complex. ACS APPLIED MATERIALS & INTERFACES 2018; 10:10227-10235. [PMID: 29504742 DOI: 10.1021/acsami.7b18330] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Cyclometalated Pt(II) complexes can show intense phosphorescence at room temperature. Their emission properties are determined by both the organic ligand and the metal center. Whereas most of the related studies focus on tuning the properties by designing different types of organic ligands, only several reports investigate the key role played by the metal center. To address this issue, phosphorescent Pt(II) complexes with one, two, and three Pt(II) centers are designed and synthesized. With more Pt(II) centers, the cyclometalated multinuclear Pt(II) complexes display red-shifted emissions with increased photoluminescence quantum yields. Most importantly, solution-processed organic light-emitting diodes (OLEDs) with the conventional device structure using the multinuclear Pt(II) complexes as emitters show excellent performance. The controlled device based on the conventional mononuclear Pt(II) complex shows a peak external quantum efficiency, current efficiency, and power efficiency of 6.4%, 14.4 cd A-1, and 12.1 lm W-1, respectively. The efficiencies are dramatically improved to 10.5%, 21.4 cd A-1, and 12.9 lm W-1 for the OLED based on the dinuclear Pt(II) complex and to 17.0%, 35.4 cd A-1, and 27.2 lm W-1 for the OLED based on the trinuclear Pt(II) complex, respectively. To the best of our knowledge, these efficiencies are among the highest ever reported for the multinuclear Pt(II) complex-based OLEDs.
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Affiliation(s)
| | | | | | | | | | | | - Wai-Yeung Wong
- Department of Applied Biology and Chemical Technology , The Hong Kong Polytechnic University , Hung Hom, Hong Kong , P. R. China
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Shi C, Li Q, Zou L, Lv Z, Yuan A, Zhao Q. A Single-Anion-Based Red-Emitting Cationic Diiridium(III) Complex Bearing a Pyrimidine-Based Bridging Ligand for Oxygen Sensing. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Chao Shi
- School of Environmental and Chemical Engineering; Jiangsu University of Science and Technology; 212003 Zhenjiang P. R. China
- School of Material Science and Engineering; Jiangsu University of Science and Technology; 212003 Zhenjiang P. R. China
| | - Qiuxia Li
- School of Material Science and Engineering; Jiangsu University of Science and Technology; 212003 Zhenjiang P. R. China
| | - Liang Zou
- Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); 210023 Nanjing P. R. China
| | - Zhuang Lv
- Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); 210023 Nanjing P. R. China
| | - Aihua Yuan
- School of Environmental and Chemical Engineering; Jiangsu University of Science and Technology; 212003 Zhenjiang P. R. China
| | - Qiang Zhao
- Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); 210023 Nanjing P. R. China
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Han HB, Cui RZ, Lu GZ, Wu ZG, Zheng YX, Zhou L, Zhang H. Efficient orange-red electroluminescence of iridium complexes with 1-(2,6-bis(trifluoromethyl)pyridin-4-yl)isoquinoline and 4-(2,6-bis(trifluoromethyl)pyridin-4-yl)quinazoline ligands. Dalton Trans 2018; 46:14916-14925. [PMID: 29043334 DOI: 10.1039/c7dt03310a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Two novel iridium(iii) complexes, Ir(tfmpiq)2(acac) (tfmpiq = 1-(2,6-bis(trifluoromethyl)pyridin-4-yl)isoquinoline, acac = acetylacetone) and Ir(tfmpqz)2(acac) (tfmpqz = 4-(2,6-bis(trifluoromethyl)pyridin-4-yl)quinazoline), were synthesized and thoroughly investigated. Both complexes emit orange-red photoluminescence with high quantum yields (Ir(tfmpiq)2(acac): λmax: 587 nm, ηPL: 42%; Ir(tfmpqz)2(acac): λmax: 588 nm, ηPL: 91%). Furthermore, the complex containing quinazoline shows higher electron mobility than that with isoquinoline. The organic light-emitting diodes (OLEDs) with single- or double-emitting layers (EML) were fabricated using two new emitters. The double-EML device using Ir(tfmpqz)2(acac) with the structure of ITO (indium-tin-oxide)/MoO3 (molybdenum oxide, 3 nm)/TAPC (di-[4-(N,N-ditolyl-amino)-phenyl]cyclohexane, 50 nm)/Ir(tfmpqz)2(acac) (1 wt%):TcTa (4,4',4''-tris(carbazole-9-yl)triphenylamine, 10 nm)/Ir(tfmpqz)2(acac) (1 wt%):2,6DCzPPy (2,6-bis(3-(carbazol-9-yl)phenyl)pyridine, 10 nm)/TmPyPB (1,3,5-tri(m-pyrid-3-yl-phenyl)benzene, 50 nm)/LiF (1 nm)/Al (100 nm) displays good electroluminescence performances with a maximum luminance of 96 609 cd m-2, a maximum current efficiency of 59.09 cd A-1, a maximum external quantum efficiency of 20.2%, a maximum power efficiency of 53.61 lm W-1, and the efficiency roll-off ratio is mild.
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Affiliation(s)
- Hua-Bo Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China.
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Hao Z, Meng F, Wang P, Wang Y, Tan H, Pei Y, Su S, Liu Y. Dual phosphorescence emission of dinuclear platinum(ii) complex incorporating cyclometallating pyrenyl-dipyridine-based ligand and its application in near-infrared solution-processed polymer light-emitting diodes. Dalton Trans 2018; 46:16257-16268. [PMID: 29138778 DOI: 10.1039/c7dt03282j] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Two novel mono- and binuclear cyclometalated platinum(ii) complexes of (BuPyrDPy)Pt(dpm) and (BuPyrDPy)[Pt(dpm)]2 incorporating a pyrenyl-dipyridine-based cyclometalated ligand were synthesized and characterized, respectively. Single-crystal X-ray diffraction of the two materials revealed each complex's coordination mode; their photophysical, electrochemical as well as electroluminescent properties were also investigated. Both complexes exhibited good solubility and excellent thermal stability. (BuPyrDPy)[Pt(dpm)]2 presented dual phosphorescence emissive character at room-temperature and showed an increased quantum efficiency compared to that of (BuPyrDPy)Pt(dpm). Density functional theory (DFT) calculations were carried out to model their photophysical process, and found a significant contribution of the second Pt center to the LUMO plot, giving the T1 and T2 states considerable LMCT nature, which is quite rare in metallic complexes. A device with the structure of ITO/PEDOT (40 nm)/PVK : 30 wt% OXD-7 : 16 wt% (BuPyrDPy)[Pt(dpm)]2 (60 nm)/TPBI (30 nm)/Ba (4 nm)/Al (100 nm) showed a stable NIR emission peak at 695 nm accompanied by two shoulders at 599 nm and 762 nm, with a maximum external quantum efficiency (EQE) of 0.31% and a radiance of 26.9 mW cm-2, which are about 2 and 1.4 times higher than those of (BuPyrDPy)Pt(dpm)-doped devices. This study provides an efficient strategy to simultaneously design novel biluminescent materials and achieve NIR emission through adjusting the emissive triplet states by introducing a second metal into an asymmetric bimetallic system.
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Affiliation(s)
- Zhaoran Hao
- College of Chemistry, Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, China.
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