1
|
Zheng SJ, Ma J, Su J, Djurovich PI, Thompson ME, Li TY. Simultaneous Thermally Stimulated Delayed Phosphorescence (TSDP) and Thermally Activated Delayed Fluorescence (TADF) in a Two-Coordinated Au(I) Bimetallic Complex Featuring a Tandem Carbene Structure. J Am Chem Soc 2024; 146:19042-19049. [PMID: 38950194 DOI: 10.1021/jacs.4c02930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
A bimetallic, two-coordinated carbene-metal-amine (cMa) Au(I) complex featuring a twisted tandem carbene structure (NHC1-Au-NHC2-Au-carbazolyl) was synthesized. The molecular structure in single crystals revealed a large dihedral angle between the two carbene ligands, while the bridged carbene NHC2 and carbazolyl (Cz) ligands were coplanar. A bluish green thermally stimulated delayed phosphorescence (TSDP) was observed in crystals with an emission lifetime over 70 μs, which can be attributed to the spin allowed diabatic population of a high-lying emissive triplet state from the 3LE characterized low-lying ones. The small rotation energy barrier of Cz along the coordination bond allowed conformers with large dihedral angles between NHC2 and Cz. The ICT characterized S1 state was consequently stabilized to achieve a thermally accessible energy gap to facilitate ISC between triplets and the S1, leading to the thermally activated delayed fluorescence (TADF). Simultaneous TSDP and TADF dual emission can be recorded in its doped polymer film owing to the coexistence of these different conformers.
Collapse
Affiliation(s)
- Shu-Jia Zheng
- Department of Chemistry, University of Science and Technology Beijing, 30 XueYuan Road, Beijing 100083, China
| | - Jie Ma
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| | - Junru Su
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| | - Peter I Djurovich
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| | - Mark E Thompson
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| | - Tian-Yi Li
- Department of Chemistry, University of Science and Technology Beijing, 30 XueYuan Road, Beijing 100083, China
- Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| |
Collapse
|
2
|
Veerapathiran S, Muduli G, Rawat A, Siddhant K, Singh J, Matsumoto K, Tsutsumi O, Prabusankar G. Organo Chalcogenone-Triggered Luminescent Copper(I) Clusters for Light Emitting Applications. Inorg Chem 2024; 63:12708-12720. [PMID: 38943619 DOI: 10.1021/acs.inorgchem.3c04637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2024]
Abstract
A novel organo sulfur and selenium-controlled emission behavior in discrete copper(I) clusters has been demonstrated for the first time. The pentanuclear [Cu5Br5(L1)2] (1), trinuclear [Cu3Br3(L2)2] (2), dinuclear [Cu2I2(L1)2] (3), and tetranuclear [Cu4I4(L2)2CH3CN] (4) copper(I) discrete clusters have been synthesized from the reaction between L1 [L1 = 1-isopropyl-3-(pyridin-2-yl)-imidazol-2-thione] or L2 [L2 = 1-isopropyl-3-(pyridin-2-yl)-imidazol-2-selone] chelating ligands and corresponding copper(I) halide salts. These new clusters have been characterized by FT-IR, UV-visible, thermogravimetric analysis, and fluorescence spectroscopy techniques. Single-crystal X-ray diffraction studies reveal that 1-4 consists of abundant d10-d10 interactions. The structural and bonding features of clusters have been investigated using density functional theory calculations. Notably, the L2-ligated 2 and 4 are poorly emissive, while L1-ligated 1 and 3 showed strong emission in the orange and green regions, respectively. The time-dependent density functional theory natural transition orbital calculations of 1 and 3 reveal the nature of the transitions contributed by 3MLCT/3LLCT/3ILCT. Photoluminescence quantum yields of 1 and 3 are 19 and 11%, with average lifetimes of 21.55 and 6.57 μs, respectively. 1 and 3 were coated on prototype LED bulbs for light-emitting performance.
Collapse
Affiliation(s)
- Sabari Veerapathiran
- Organometallics and Materials Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India
| | - Gopendra Muduli
- Organometallics and Materials Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India
| | - Arushi Rawat
- Department of Applied Chemistry, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Kumar Siddhant
- Department of Applied Chemistry, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Joginder Singh
- Organometallics and Materials Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India
| | - Kohsuke Matsumoto
- Department of Applied Chemistry, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Osamu Tsutsumi
- Department of Applied Chemistry, Ritsumeikan University, Kusatsu 525-8577, Japan
| | - Ganesan Prabusankar
- Organometallics and Materials Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India
| |
Collapse
|
3
|
Li R, Ying A, Tan Y, Ai Y, Gong S. Efficient Blue Photo- and Electroluminescence from CF 3-Decorated Cu(I) Complexes. Chemistry 2024; 30:e202400817. [PMID: 38654445 DOI: 10.1002/chem.202400817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 04/26/2024]
Abstract
Luminescent organometallic complexes of earth-abundant copper(I) have long been studied in organic light-emitting diodes (OLED). Particularly, Cu(I)-based carbene-metal-amide (CMA) complexes have recently emerged as promising organometallic emitters. However, blue-emitting Cu(I) CMA complexes have been rarely reported. Here we constructed two blue-emitting Cu(I) CMA emitters, MAC*-Cu-CF3Cz and MAC*-Cu-2CF3Cz, by introducing one or two CF3 substitutes into carbazole ligands. Both complexes exhibited high thermal stability and blue emission colors. Moreover, two complexes exhibited different emission origins rooting from different donor ligands: a distinct thermally activated delayed fluorescence (TADF) from ligand-to-ligand charge transfer excited states for MAC*-Cu-CF3Cz or a dominant phosphorescence nature from local triplet excited state of the carbazole ligand for MAC*-Cu-2CF3Cz. Inspiringly, MAC*-Cu-CF3Cz had high photoluminescence quantum yields of up to 94 % and short emission lifetimes of down to 1.2 μs in doped films, accompanied by relatively high radiative rates in the 105 s-1 order. The resultant vacuum-deposited OLEDs based on MAC*-Cu-CF3Cz delivered pure-blue electroluminescence at 462 nm together with a high external quantum efficiency of 13.0 %.
Collapse
Affiliation(s)
- Ruoyan Li
- College of Chemistry and Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| | - Ao Ying
- College of Chemistry and Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| | - Yao Tan
- College of Chemistry and Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| | - Yuhan Ai
- College of Chemistry and Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| | - Shaolong Gong
- College of Chemistry and Molecular Sciences, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| |
Collapse
|
4
|
Chatterjee J, Chatterjee A, Tanwar R, Panwaria P, Saikia S, Ambhore MD, Mandal P, Hazra P. Activation of TADF in Photon Upconverting Crystals of Dinuclear Cu(I)-Iodide Complexes by Ligand Engineering. J Phys Chem Lett 2024; 15:6069-6080. [PMID: 38820068 DOI: 10.1021/acs.jpclett.4c01122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2024]
Abstract
This work reports that ligand engineering can modulate the triplet harvesting mechanism in iodide-bridged rhombic Cu2I2 complexes. Complex-1, with a smaller Cu-Cu distance, exhibits phosphorescence from 3(M+X)LCT and 3CC states with 66% quantum yield, whereas an increased Cu-Cu distance in complex-2 results in a switch of the emission from phosphorescence to TADF, which occurs via 1/3(M+X)LCT states with 83% quantum yield. The TADF property of complex-2 has been utilized for the fabrication of a pc-LED emitting efficient warm white light. Moreover, the high charge-transfer nature of these complexes leads to the emergence of third-harmonic generation (THG). Interestingly, complex-1 exhibits efficient third-harmonic generation with a χ(3) value of 1.15 × 10-18 m2 V-2 and LIDT value of 14.73 GW/cm2. This work aims to provide a structure-property relationship to achieve effective harvestation of triplet excitons in iodide-bridged rhombic Cu2I2 complexes and their effective utilization in OLED device fabrication and nonlinear photon upconversion processes.
Collapse
Affiliation(s)
- Joy Chatterjee
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Abhijit Chatterjee
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Riteeka Tanwar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Sajid Saikia
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Madan D Ambhore
- Department of Chemistry, Yeshwant Mahavidyalaya Nanded, Nanded, PIN-431602, Maharashtra, India
| | - Pankaj Mandal
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| | - Partha Hazra
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune-411008, Maharashtra, India
| |
Collapse
|
5
|
Brannan AC, Cho HH, Reponen APM, Gorgon S, Phuoc NL, Linnolahti M, Greenham NC, Romanov AS. Deep-Blue and Fast Delayed Fluorescence from Carbene-Metal-Amides for Highly Efficient and Stable Organic Light-Emitting Diodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2404357. [PMID: 38727713 DOI: 10.1002/adma.202404357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/06/2024] [Indexed: 05/21/2024]
Abstract
Linear gold complexes of the "carbene-metal-amide" (CMA) type are prepared with a rigid benzoguanidine amide donor and various carbene ligands. These complexes emit in the deep-blue range at 424 and 466 nm with 100% quantum yields in all media. The deep-blue thermally activates delayed fluorescence originates from a charge transfer state with an excited state lifetime as low as 213 ns, resulting in fast radiative rates of 4.7 × 106 s-1. The high thermal and photo-stability of these carbene-metal-amide (CMA) materials enabled the authors to fabricate highly energy-efficient organic light-emitting diodes (OLED) in host-guest architectures. Deep-blue OLED devices with electroluminescence at 416 and 457 nm with practical external quantum efficiencies of up to 23% at 100 cd m-2 with excellent color coordinates CIE (x; y) = 0.16; 0.07 and 0.17; 0.18 are reported. The operating stability of these OLEDs is the longest reported to date (LT50 = 1 h) for deep-blue CMA emitters, indicating a high promise for further development of blue OLED devices. These findings inform the molecular design strategy and correlation between delayed luminescence with high radiative rates and CMA OLED device operating stability.
Collapse
Affiliation(s)
- Alexander C Brannan
- Department of Chemistry, The University of Manchester, Oxford Rd, Manchester, M13 9PL, UK
| | - Hwan-Hee Cho
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Antti-Pekka M Reponen
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Sebastian Gorgon
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Nguyen Le Phuoc
- Department of Chemistry, University of Eastern Finland, Joensuu, FI-80101, Finland
| | - Mikko Linnolahti
- Department of Chemistry, University of Eastern Finland, Joensuu, FI-80101, Finland
| | - Neil C Greenham
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Alexander S Romanov
- Department of Chemistry, The University of Manchester, Oxford Rd, Manchester, M13 9PL, UK
| |
Collapse
|
6
|
Zhang X, Song JX, Chang X, Li K, Chen Y. Thermally Activated Delayed Fluorescent Binuclear Copper(I) Alkynyl Complexes with Cuprophilic Interactions. Chemistry 2024; 30:e202304224. [PMID: 38414117 DOI: 10.1002/chem.202304224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/06/2024] [Accepted: 02/27/2024] [Indexed: 02/29/2024]
Abstract
Copper(I)-based thermally activated delayed fluorescence (TADF) emitters have been conceived to be promising candidates for display and lighting applications because of their multifarious structures and strong photoluminescence. Herein a string of binuclear Cu(I) complexes bearing pronounced cuprophilic interactions have been designed and synthesized. [Cu2(dppb)2(μ2-η1-C≡C-Ph)2] (1 a) and [Cu2(dppb)2(μ2-η1-C≡C-PPXZ)2] (1 b) display photoluminescence quantum yields of up to 67 % in doped films and solid states via TADF and exhibit reversible bicolor luminescence switching upon mechanical stimuli. Computational studies manifest that the metal-to-ligand charge transfer predominant transitions ensure a small energy splitting (ΔEST) between the lowest singlet (S1) and triplet (T1) excited states and cuprophilic interactions promote the spin-orbit coupling (SOC), favoring the reverse intersystem crossing (RISC) process. This study provides a new strategy for the construction of stimuli-responsive metal-based TADF materials.
Collapse
Affiliation(s)
- Xi Zhang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Jia-Xi Song
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Xiaoyong Chang
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P.R. China
| | - Kai Li
- College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P.R. China
| | - Yong Chen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| |
Collapse
|
7
|
Li TY, Zheng SJ, Djurovich PI, Thompson ME. Two-Coordinate Thermally Activated Delayed Fluorescence Coinage Metal Complexes: Molecular Design, Photophysical Characters, and Device Application. Chem Rev 2024; 124:4332-4392. [PMID: 38546341 DOI: 10.1021/acs.chemrev.3c00761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Since the emergence of the first green light emission from a fluorescent thin-film organic light emitting diode (OLED) in the mid-1980s, a global consumer market for OLED displays has flourished over the past few decades. This growth can primarily be attributed to the development of noble metal phosphorescent emitters that facilitated remarkable gains in electrical conversion efficiency, a broadened color gamut, and vibrant image quality for OLED displays. Despite these achievements, the limited abundance of noble metals in the Earth's crust has spurred ongoing efforts to discover cost-effective electroluminescent materials. One particularly promising avenue is the exploration of thermally activated delayed fluorescence (TADF), a mechanism with the potential to fully harness excitons in OLEDs. Recently, investigations have unveiled TADF in a series of two-coordinate coinage metal (Cu, Ag, and Au) complexes. These organometallic TADF materials exhibit distinctive behavior in comparison to their organic counterparts. They offer benefits such as tunable emissive colors, short TADF emission lifetimes, high luminescent quantum yields, and reasonable stability. Impressively, both vacuum-deposited and solution-processed OLEDs incorporating these materials have achieved outstanding performance. This review encompasses various facets on two-coordinate TADF coinage metal complexes, including molecular design, photophysical characterizations, elucidation of structure-property relationships, and OLED applications.
Collapse
Affiliation(s)
- Tian-Yi Li
- Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Shu-Jia Zheng
- Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Peter I Djurovich
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Mark E Thompson
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| |
Collapse
|
8
|
Yan J, Wu C, Tong KN, Zhou F, Chen Y, Pan Y, Xie G, Chi Y, Lau KC, Wei G. Structural Engineering of Iridium(III) Phosphors with Imidazo[4,5-b]pyrazin-2-ylidene Cyclometalates for Efficient Blue Electroluminescence. SMALL METHODS 2024:e2301555. [PMID: 38185747 DOI: 10.1002/smtd.202301555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/27/2023] [Indexed: 01/09/2024]
Abstract
Iridium(III) complexes are particularly noted for their excellent potentials in fabrication of blue organic light-emitting diodes (OLEDs), but the severe efficiency roll-off largely hampered their practical applications. To reveal the underlying characteristics, three Ir(III) complexes, namely f-ct5c, f-ct5d, and f-ct11, bearing imidazo[4,5-b]pyrazin-2-ylidene cyclometalates are prepared and characterized in detail. Both f-ct5c and f-ct5d (also their mixture f-ct5mix) gave intensive blue emissions peaking at ≈465 nm with short radiative lifetimes of 1.76 and 2.45 µs respectively, in degassed toluene. Alternatively, f-ct11 with two 4-tert-butylphenyl substituents on each imidazo[4,5-b]pyrazin-2-ylidene entity, possessed a bluish-green emission (508 nm) together with an extended radiative lifetime of 34.3 µs in the dispersed PMMA matrix. Consequently, the resulting solution-processed OLED with f-ct11 delivered a maximum external quantum efficiency (EQEmax ) of 6.5% with serious efficiency roll-offs. In contrast, f-ct5mix based device achieved a high EQEmax of 27.2% and the EQE maintained at 23.0% of 1000 cd m-2 . Furthermore, the hyper-OLEDs with f-ct5mix as the sensitizer and v-DABNA as the terminal emitter afford narrowed emission with a considerably high EQEmax exceeding 32%, affirming the potential of f-ct5mix to serve as both the emitter and sensitizer in OLEDs.
Collapse
Affiliation(s)
- Jie Yan
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Chengcheng Wu
- Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen, 518055, China
| | - Kai-Ning Tong
- Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen, 518055, China
| | - Fan Zhou
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Yidong Chen
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Yi Pan
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Guohua Xie
- The Institute of Flexible Electronics (Future Technologies), Xiamen University, Xiamen, 361005, China
| | - Yun Chi
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Kai-Chung Lau
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, 999077, HONG KONG
| | - Guodan Wei
- Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen, 518055, China
| |
Collapse
|
9
|
Avula S, Jhun BH, Jo U, Heo S, Lee JY, You Y. Achieving Long-Wavelength Electroluminescence Using Two-Coordinate Gold(I) Complexes: Overcoming the Energy Gap Law. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305745. [PMID: 37953418 PMCID: PMC10767458 DOI: 10.1002/advs.202305745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/05/2023] [Indexed: 11/14/2023]
Abstract
Two-coordinate coinage metal complexes have emerged as promising emitters for highly efficient organic light-emitting devices (OLEDs). However, achieving efficient long-wavelength electroluminescence emission from these complexes remains as a daunting challenge. To address this challenge, molecular design strategies aimed at bolstering the photoluminescence quantum yield (Φ) of Au(I) complex emitters in low-energy emission regions are investigated. By varying amido ligands, a series of two-coordinate Au(I) complexes is developed that exhibit photoluminescence peak wavelengths over a broad range of 533-750 nm. These complexes, in particular, maintain Φ values up to 10% even in the near-infrared emission region, overcoming the constraints imposed by an energy gap. Quantum chemical calculations and photophysical analyses reveal the action of radiative control, which serves to overcome the energy gap law, becomes more pronounced as the overlap between hole and electron distributions (Sr (r)) in the excited state increases. It is further elucidated that Sr (r) increases with the distance between the hole-distribution centroid and the nitrogen atom in an amido ligand. Finally, multilayer OLEDs involving the Au(I) complex emitters exhibit performances beyond the borderline of the electroluminescence wavelength-external quantum efficiency space set by previous devices of coinage metal complexes.
Collapse
Affiliation(s)
- Sreenivas Avula
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
| | - Byung Hak Jhun
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
| | - Unhyeok Jo
- School of Chemical EngineeringSungkyunkwan UniversitySuwonGyeonggi‐do16419Republic of Korea
| | - Seunga Heo
- Division of Chemical Engineering and Materials ScienceEwha Womans UniversitySeoul03760Republic of Korea
| | - Jun Yeob Lee
- School of Chemical EngineeringSungkyunkwan UniversitySuwonGyeonggi‐do16419Republic of Korea
| | - Youngmin You
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
| |
Collapse
|
10
|
Song XF, Peng LY, Chen WK, Gao YJ, Cui G. Theoretical studies on thermally activated delayed fluorescence of "carbene-metal-amide" Cu and Au complexes: geometric structures, excitation characters, and mechanisms. Phys Chem Chem Phys 2023; 25:29603-29613. [PMID: 37877743 DOI: 10.1039/d3cp03444e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
"Carbene-metal(I)-amide" (CMA) complexes have garnered significant attention due to their remarkable properties and potential TADF applications in organic electronics. However, the atomistic working mechanism is still elusive. Herein, we chose two CMA complexes, i.e., cyclic (alkyl)(amino) carbene-copper[gold](I)-carbazole (CAAC-Cu[Au]-Cz), and employed both DFT and TD-DFT methods, in combination with radiative and nonradiative rate calculations, to investigate geometric and electronic structures of these two complexes in the ground and excited states, including orbital compositions, electronic transitions, absorption and emission spectra, and the luminescence mechanism. It is found that the coplanar or perpendicular conformations are coexistent in the ground state (S0), the lowest excited singlet state (S1), and the triplet state (T1). Both the coplanar and perpendicular S1 and T1 states have similar ligand-to-ligand charge transfer (LLCT) character between CAAC and Cz, and some charge-transfer character between metal atoms and ligands, which is beneficial to minimize the singlet-triplet energy gaps (ΔEST) and increase the spin-orbit coupling (SOC). An interesting three-state (S0, S1, T1) model involving two regions (coplanar and perpendicular) is proposed to rationalize the experimental TADF phenomena in the CMA complexes. In addition to the coplanar ones, the perpendicular S1 and T1 states also play a role in promoting the repopulation of the coplanar S1 exciton, which is a primary source for the delayed fluorescence.
Collapse
Affiliation(s)
- Xiu-Fang Song
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University, Beijing 100875, P. R. China.
| | - Ling-Ya Peng
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University, Beijing 100875, P. R. China.
| | - Wen-Kai Chen
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University, Beijing 100875, P. R. China.
| | - Yuan-Jun Gao
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China.
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University, Beijing 100875, P. R. China.
- Hefei National Laboratory, Hefei 230088, China
| |
Collapse
|
11
|
Ying A, Gong S. A Rising Star: Luminescent Carbene-Metal-Amide Complexes. Chemistry 2023; 29:e202301885. [PMID: 37431981 DOI: 10.1002/chem.202301885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/12/2023]
Abstract
Coinage metal (gold, silver, and copper) complexes are attractive candidates to substitute the widely studied noble metal complexes, such as, iridium(III) and platinum(II), as luminescent materials in organic light-emitting diodes (OLEDs). However, the development of coinage metal complexes exhibiting high emission quantum yields and short exciton lifetimes is still a formidable challenge. In the past few years, coinage metal complexes featuring a carbene-metal-amide (CMA) motif have emerged as a new class of luminescent materials in OLEDs. Thanks to the coinage metal-bridged linear geometry, coplanar conformation, and the formation of excited states with dominant ligand-to-ligand charge transfer character and reduced metal d-orbital participation, most CMA complexes have high radiative rates via thermally activated delayed fluorescence. Currently, the family of CMA complexes have rapidly evolved and remarkable progresses in CMA-based OLEDs have been made. Here, a Concept article on CMA complexes is presented, with a focus on molecular design principles, the correlation between molecular structure/conformation and optoelectronic properties, as well as OLED performance. The future prospects of CMA complexes are also discussed.
Collapse
Affiliation(s)
- Ao Ying
- Hubei Key Lab on Organic and, Polymeric Optoelectronic Materials, Department of Chemistry, Wuhan University, Wuhan, 430072, China
| | - Shaolong Gong
- Hubei Key Lab on Organic and, Polymeric Optoelectronic Materials, Department of Chemistry, Wuhan University, Wuhan, 430072, China
| |
Collapse
|
12
|
Powley SL, Riley C, Cho HH, Le Phuoc N, Linnolahti M, Greenham N, Romanov AS. Highly phosphorescent carbene-metal-carboranyl complexes of copper(I) and gold(I). Chem Commun (Camb) 2023; 59:12035-12038. [PMID: 37729393 DOI: 10.1039/d3cc04091g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
New phosphorescent "carbene-metal-carboranyl" (CMC) Cu(I) and Au(I) complexes based on the diamidocarbene (DAC) ligand show up to 68% photoluminescence quantum yield and microsecond range lifetimes. CMC organic light emitting diodes (OLEDs) emit sky-blue and warm white electroluminescence.
Collapse
Affiliation(s)
- Samuel L Powley
- Department of Chemistry, The University of Manchester, Oxford Rd., Manchester, M13 9PL, UK.
| | - Charlotte Riley
- Department of Chemistry, The University of Manchester, Oxford Rd., Manchester, M13 9PL, UK.
| | - Hwan-Hee Cho
- Department of Physics, Cavendish Laboratory, Cambridge University, Cambridge CB3 0HE, UK.
| | - Nguyen Le Phuoc
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, FI-80101 Joensuu, Finland.
| | - Mikko Linnolahti
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, FI-80101 Joensuu, Finland.
| | - Neil Greenham
- Department of Physics, Cavendish Laboratory, Cambridge University, Cambridge CB3 0HE, UK.
| | - Alexander S Romanov
- Department of Chemistry, The University of Manchester, Oxford Rd., Manchester, M13 9PL, UK.
| |
Collapse
|
13
|
Ma J, Schaab J, Paul S, Forrest SR, Djurovich PI, Thompson ME. Luminescent Bimetallic Two-Coordinate Gold(I) Complexes Utilizing Janus Carbenes. J Am Chem Soc 2023; 145:20097-20108. [PMID: 37642694 DOI: 10.1021/jacs.3c07743] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
A series of bimetallic carbene-metal-amide (cMa) complexes have been prepared with bridging biscarbene ligands to serve as a model for the design of luminescent materials with large oscillator strengths and small energy differences between the singlet and triplet states (ΔEST). The complexes have a general structure (R2N)Au(:carbene─carbene:)Au(NR2). The bimetallic complexes show solvation-dependent absorption and emission that is analyzed in detail. It is found that the molar absorptivity of the bimetallic complexes is correlated with the energy barrier to rotation of the metal-ligand bond. The bimetallic cMa complexes also exhibit short emission lifetimes (τ = 200-300 ns) with high photoluminescence efficiencies (ΦPL > 95%). The radiative rates of bimetallic cMa complexes are 3-4 times faster than that of the corresponding monometallic complexes. Analysis of temperature-dependent luminescence data indicates that the lifetime for the singlet state (τS1) of bimetallic cMa complexes is near 12 ns with a ΔEST of 40-50 meV. The presented compounds provide a general design for cMa complexes to achieve small values for ΔEST while retaining high radiative rates. Solution-processed organic light-emitting devices (OLEDs) made using two of the complexes as luminescent dopants show high efficiency and low roll-off at high luminance.
Collapse
Affiliation(s)
- Jie Ma
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, United States
| | - Jonas Schaab
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Sritoma Paul
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Stephen R Forrest
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Peter I Djurovich
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Mark E Thompson
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, United States
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| |
Collapse
|
14
|
Muniz CN, Archer CA, Applebaum JS, Alagaratnam A, Schaab J, Djurovich PI, Thompson ME. Two-Coordinate Coinage Metal Complexes as Solar Photosensitizers. J Am Chem Soc 2023. [PMID: 37319428 DOI: 10.1021/jacs.3c02825] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Generating sustainable fuel from sunlight plays an important role in meeting the energy demands of the modern age. Herein, we report two-coordinate carbene-metal-amide (cMa, M = Cu(I) and Au(I)) complexes that can be used as sensitizers to promote the light-driven reduction of water to hydrogen. The cMa complexes studied here absorb visible photons (εvis > 103 M-1 cm-1), maintain long excited-state lifetimes (τ ∼ 0.2-1 μs), and perform stable photoinduced charge transfer to a target substrate with high photoreducing potential (E+/* up to -2.33 V vs Fc+/0 based on a Rehm-Weller analysis). We pair these coinage metal complexes with a cobalt-glyoxime electrocatalyst to photocatalytically generate hydrogen and compare the performance of the copper- and gold-based cMa complexes. We also find that the two-coordinate complexes herein can perform photodriven hydrogen production from water without the addition of the cobalt-glyoxime electrocatalyst. In this "catalyst-free" system, the cMa sensitizer partially decomposes to give metal nanoparticles that catalyze water reduction. This work identifies two-coordinate coinage metal complexes as promising abundant metal, solar fuel photosensitizers that offer exceptional tunability and photoredox properties.
Collapse
Affiliation(s)
- Collin N Muniz
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Claire A Archer
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Jack S Applebaum
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Anushan Alagaratnam
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Jonas Schaab
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Peter I Djurovich
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Mark E Thompson
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| |
Collapse
|
15
|
Mrózek O, Mitra M, Hupp B, Belyaev A, Lüdtke N, Wagner D, Wang C, Wenger OS, Marian CM, Steffen A. An Air- and Moisture-stable Zinc(II) Carbene Dithiolate Dimer Showing Fast Thermally Activated Delayed Fluorescence and Dexter Energy Transfer Catalysis. Chemistry 2023; 29:e202203980. [PMID: 36637038 DOI: 10.1002/chem.202203980] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/06/2023] [Accepted: 01/09/2023] [Indexed: 01/14/2023]
Abstract
A dimeric ZnII carbene complex featuring bridging and chelating benzene-1,2-dithiolate ligands is highly stable towards air and water. The donor-Zn-acceptor structure leads to visible light emission in the solid state, solution and polymer matrices with λmax between 577-657 nm and, for zinc(II) complexes, unusually high radiative rate constants for triplet exciton decay of up to kr =1.5×105 s-1 at room temperature. Variable temperature and DFT/MRCI studies show that a small energy gap between the 1/3 LL/LMCT states of only 79 meV is responsible for efficient thermally activated delayed fluorescence (TADF). Time-resolved luminescence and transient absorption studies confirm the occurrence of long-lived, dominantly ligand-to-ligand charge transfer excited states in solution, allowing for application in Dexter energy transfer photocatalysis.
Collapse
Affiliation(s)
- Ondřej Mrózek
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Mousree Mitra
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Bejamin Hupp
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Andrey Belyaev
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| | - Nora Lüdtke
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Dorothee Wagner
- Department of Chemistry, University of Basel, 4056, Basel, Switzerland
| | - Cui Wang
- Department of Chemistry, University of Basel, 4056, Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, 4056, Basel, Switzerland
| | - Christel M Marian
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Andreas Steffen
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany
| |
Collapse
|
16
|
Cai S, Tong GSM, Du L, So GKM, Hung FF, Lam TL, Cheng G, Xiao H, Chang X, Xu ZX, Che CM. Gold(I) Multi-Resonance Thermally Activated Delayed Fluorescent Emitters for Highly Efficient Ultrapure-Green Organic Light-Emitting Diodes. Angew Chem Int Ed Engl 2022; 61:e202213392. [PMID: 36288083 DOI: 10.1002/anie.202213392] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Indexed: 11/06/2022]
Abstract
Acceleration of singlet-triplet intersystem crossings (ISC) is instrumental in bolstering triplet exciton harvesting of multi-resonance thermally activated delayed fluorescent (MR-TADF) emitters. This work describes a simple gold(I) coordination strategy to enhance the spin-orbit coupling of green and blue BN(O)-based MR-TADF emitters, which results in a notable increase in rate constants of the spectroscopically observed ISC process to 3×109 s-1 with nearly unitary ISC quantum yields. Accordingly, the resultant thermally-stable AuI emitters attained large values of delayed fluorescence radiative rate constant up to 1.3×105 /1.7×105 s-1 in THF/PMMA film while preserving narrowband emissions (FWHM=30-37 nm) and high emission quantum yields (ca. 0.9). The vapor-deposited ultrapure-green OLEDs fabricated with these AuI emitters delivered high luminance of up to 2.53×105 cd m-2 as well as external quantum efficiencies of up to 30.3 % with roll-offs as low as 0.8 % and long device lifetimes (LT60 ) of 1210 h at 1000 cd m-2 .
Collapse
Affiliation(s)
- Siyuan Cai
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Department of Chemistry, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, P. R. China
| | - Glenna So Ming Tong
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Hong Kong Quantum AI Lab Limited, Units 909-915, Building 17W, 17 Science Park West Avenue, Hong Kong Science Park, Pak Shek Kok, Hong Kong, P. R. China
| | - Lili Du
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,School of Life Science, Jiangsu University, Zhenjiang, 212013, P. R. China
| | - Gary Kwok-Ming So
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - Faan-Fung Hung
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Hong Kong Quantum AI Lab Limited, Units 909-915, Building 17W, 17 Science Park West Avenue, Hong Kong Science Park, Pak Shek Kok, Hong Kong, P. R. China
| | - Tsz-Lung Lam
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Hong Kong Quantum AI Lab Limited, Units 909-915, Building 17W, 17 Science Park West Avenue, Hong Kong Science Park, Pak Shek Kok, Hong Kong, P. R. China
| | - Gang Cheng
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Hong Kong Quantum AI Lab Limited, Units 909-915, Building 17W, 17 Science Park West Avenue, Hong Kong Science Park, Pak Shek Kok, Hong Kong, P. R. China.,HKU Shenzhen Institute of Research and Innovation, Shenzhen, Guangdong, 518057, P. R. China
| | - Hui Xiao
- Department of Chemistry, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, P. R. China
| | - Xiaoyong Chang
- Department of Chemistry, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, P. R. China
| | - Zong-Xiang Xu
- Department of Chemistry, Southern University of Science and Technology of China, Shenzhen, Guangdong, 518055, P. R. China
| | - Chi-Ming Che
- Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.,Hong Kong Quantum AI Lab Limited, Units 909-915, Building 17W, 17 Science Park West Avenue, Hong Kong Science Park, Pak Shek Kok, Hong Kong, P. R. China.,HKU Shenzhen Institute of Research and Innovation, Shenzhen, Guangdong, 518057, P. R. China
| |
Collapse
|
17
|
Gao Y, Wu S, Shan G, Cheng G. Recent Progress in Blue Thermally Activated Delayed Fluorescence Emitters and Their Applications in OLEDs: Beyond Pure Organic Molecules with Twist D-π-A Structures. MICROMACHINES 2022; 13:2150. [PMID: 36557449 PMCID: PMC9784815 DOI: 10.3390/mi13122150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Thermally activated delayed fluorescence (TADF) materials, which can harvest all excitons and emit light without the use of noble metals, are an appealing class of functional materials emerging as next-generation organic electroluminescent materials. Triplet excitons can be upconverted to the singlet state with the aid of ambient thermal energy under the reverse inter-system crossing owing to the small singlet-triplet splitting energy (ΔEST). This results from a specific molecular design consisting of minimal overlap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, due to the spatial separation of the electron-donating and electron-releasing part. When a well-designed device structure is applied, high-performance blue-emitting TADF organic light-emitting diodes can be realized with an appropriate molecular design. Unlike the previous literature that has reviewed general blue-emitting TADF materials, in this paper, we focus on materials other than pure organic molecules with twist D-π-A structures, including multi-resonance TADF, through-space charge transfer TADF, and metal-TADF materials. Cutting-edge molecules with extremely small and even negative ΔEST values are also introduced as candidates for next-generation TADF materials. In addition, OLED structures used to exploit the merits of the abovementioned TADF emitters are also described in this review.
Collapse
Affiliation(s)
- Yiting Gao
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Siping Wu
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Guogang Shan
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Gang Cheng
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
- HKU Shenzhen Institute of Research and Innovation, Shenzhen 518053, China
| |
Collapse
|
18
|
Zhou D, Tong GSM, Cheng G, Tang YK, Liu W, Ma D, Du L, Chen JR, Che CM. Stable Tetradentate Gold(III)-TADF Emitters with Close to Unity Quantum Yield and Radiative Decay Rate Constant of up to 2 × 10 6 s -1 : High-Efficiency Green OLEDs with Operational Lifetime (LT 90 ) Longer than 1800 h at 1000 cd m -2. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2206598. [PMID: 36208071 DOI: 10.1002/adma.202206598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/23/2022] [Indexed: 06/16/2023]
Abstract
High maximum external quantum efficiency (EQEmax ), small efficiency roll-offs, and long operational lifetime at practical luminances are three crucial parameters for commercialization of organic light-emitting diodes (OLEDs). To simultaneously achieve these goals, it is desirable to have the radiative decay rate constant (kr ) as large as possible, which, for a thermally activated delayed fluorescent (TADF) emitter, requires both a large S1 →S0 radiative decay rate constant (kr S ) and a small singlet-triplet energy gap (ΔEST ). Here, the design of a class of tetradentate gold(III) TADF complexes for narrowing the ΔEST while keeping the kr S large is reported. The as-synthesized complexes display green emission with close to unity emission quantum yields, and kr approaching 2 × 106 s-1 in thin films. The vacuum-deposited green OLEDs based on 1 and 4 demonstrate maximum EQEs of up to 24 and 27% with efficiency roll-offs of 5.5 and 2.2% at 1000 cd m-2 , respectively; the EQEs maintain high at 10 000 cd m-2 (19% (1) and 24% (4)). A long LT90 device lifetime of 1820 h at 1000 cd m-2 for complex 1 is achieved, which is one of the longest device lifetimes of TADF-OLEDs reported in the literature.
Collapse
Affiliation(s)
- Dongling Zhou
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Glenna So Ming Tong
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Gang Cheng
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, Guangdong, 515041, China
| | - Yu-Kan Tang
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Wei Liu
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology Guangzhou, Guangzhou, 510640, China
| | - Dongge Ma
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology Guangzhou, Guangzhou, 510640, China
| | - Lili Du
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
- School of Life Science, Jiangsu University, Zhenjiang, 212013, China
| | - Jian-Rui Chen
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, Guangdong, 515041, China
| | - Chi-Ming Che
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, Guangdong, 515041, China
| |
Collapse
|
19
|
Beaudelot J, Oger S, Peruško S, Phan TA, Teunens T, Moucheron C, Evano G. Photoactive Copper Complexes: Properties and Applications. Chem Rev 2022; 122:16365-16609. [PMID: 36350324 DOI: 10.1021/acs.chemrev.2c00033] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Photocatalyzed and photosensitized chemical processes have seen growing interest recently and have become among the most active areas of chemical research, notably due to their applications in fields such as medicine, chemical synthesis, material science or environmental chemistry. Among all homogeneous catalytic systems reported to date, photoactive copper(I) complexes have been shown to be especially attractive, not only as alternative to noble metal complexes, and have been extensively studied and utilized recently. They are at the core of this review article which is divided into two main sections. The first one focuses on an exhaustive and comprehensive overview of the structural, photophysical and electrochemical properties of mononuclear copper(I) complexes, typical examples highlighting the most critical structural parameters and their impact on the properties being presented to enlighten future design of photoactive copper(I) complexes. The second section is devoted to their main areas of application (photoredox catalysis of organic reactions and polymerization, hydrogen production, photoreduction of carbon dioxide and dye-sensitized solar cells), illustrating their progression from early systems to the current state-of-the-art and showcasing how some limitations of photoactive copper(I) complexes can be overcome with their high versatility.
Collapse
Affiliation(s)
- Jérôme Beaudelot
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Samuel Oger
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
| | - Stefano Peruško
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium.,Organic Synthesis Division, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020Antwerp, Belgium
| | - Tuan-Anh Phan
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Titouan Teunens
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium.,Laboratoire de Chimie des Matériaux Nouveaux, Université de Mons, Place du Parc 20, 7000Mons, Belgium
| | - Cécile Moucheron
- Laboratoire de Chimie Organique et Photochimie, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/08, 1050Brussels, Belgium
| | - Gwilherm Evano
- Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50 - CP160/06, 1050Brussels, Belgium
| |
Collapse
|
20
|
Muniz CN, Schaab J, Razgoniaev A, Djurovich PI, Thompson ME. π-Extended Ligands in Two-Coordinate Coinage Metal Complexes. J Am Chem Soc 2022; 144:17916-17928. [PMID: 36126274 DOI: 10.1021/jacs.2c06948] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Two-coordinate carbene-MI-amide (cMa, MI = Cu, Ag, Au) complexes have emerged as highly efficient luminescent materials for use in a variety of photonic applications due to their extremely fast radiative rates through thermally activated delayed fluorescence (TADF) from an interligand charge transfer (ICT) process. A series of cMa derivatives was prepared to examine the variables that affect the radiative rate, with the goal of understanding the parameters that control the radiative TADF process in these materials. We find that blue-emissive complexes with high photoluminescence efficiencies (ΦPL > 0.95) and fast radiative rates (kr = 4 × 106 s-1) can be achieved by selectively extending the π-system of the carbene and amide ligands. Of note is the role played by the increased separation between the hole and electron in the ICT excited state. Analysis of temperature-dependent luminescence data and theoretical calculations indicate that the hole-electron separation exerts a primary effect on the energy gap between the lowest-energy singlet and triplet states (ΔEST) while keeping the radiative rate for the singlet state relatively unchanged. This interpretation provides guidelines for the design of new cMa derivatives with even faster radiative rates in addition to those with slower radiative rates and thus extended excited state lifetimes.
Collapse
Affiliation(s)
- Collin N Muniz
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Jonas Schaab
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Anton Razgoniaev
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Peter I Djurovich
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Mark E Thompson
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| |
Collapse
|