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Dhineshkumar E, Arumugam N, Manikandan E, Maaza M, Mandal A. Fabrication of high performance based deep-blue OLED with benzodioxin-6-amine-styryl-triphenylamine and carbazole hosts as electroluminescent materials. Sci Rep 2024; 14:2432. [PMID: 38287065 PMCID: PMC10825205 DOI: 10.1038/s41598-023-50867-x] [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: 10/12/2023] [Accepted: 12/27/2023] [Indexed: 01/31/2024] Open
Abstract
The present study reports synthesis of phenathroimidazole derivatives structures following donor-acceptor relation for high performance deep-blue light emitting diodes. Herein, methyl substituted benzodioxin-6-amine phenanthroimidazoles Cz-SBDPI and TPA-SBDPI derivatives that provide the blue light were designed and synthesized. These Cz-SBDPI and TPA-SBDPI show higher glass transition (Tg) temperatures of 199 and 194 °C and demonstrate enhanced thermal properties. Apart from enhanced thermal stability these compounds also exhibit superior photophysical, electrochemical and electroluminescent properties. The non-doped carbazole based device display improved electroluminescent performances than those of TPA-based devices. The strong orbital-coupling due to decreased energy barrier between Cz-SBDPI transitions result in deep blue emission with CIE-0.15, 0.06. For non-doped Cz-SBDPI device; high L (brightness):12,984 cd/m2; ηc (current efficiency): 5.9 cd/A; ηp (power efficiency): 5.7 lm/W and ηex (external quantum efficiency): 6.2% was observed. The results show that the D-A emitters can serve as simple but also as an effective approach to devise cheap electroluminescent materials that has high efficiency and can serve as OLED devices.
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Affiliation(s)
- E Dhineshkumar
- Manushyaa Blossom Pvt. Ltd., Chennai, Tamil Nadu, 600102, India
| | - N Arumugam
- Department of Biotechnology, School of Life Sciences, Pondicherry University (A Central University), Puducherry, 605014, India
| | - E Manikandan
- Centre for Nanoscience and Technology, MSGET, Pondicherry University (A Central University), Puducherry, 605014, India.
- College of Graduate Studies, UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, Muckleneuk Ridge, PO Box 392, Pretoria, South Africa.
- Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West, PO Box 722, Western Cape, 7129, South Africa.
| | - M Maaza
- College of Graduate Studies, UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, Muckleneuk Ridge, PO Box 392, Pretoria, South Africa.
- Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West, PO Box 722, Western Cape, 7129, South Africa.
| | - Abhishek Mandal
- Department of Biotechnology, School of Life Sciences, Pondicherry University (A Central University), Puducherry, 605014, India.
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Jayabharathi J, Anudeebhana J, Thanikachalam V, Sivaraj S, Prabhakaran A. Efficient donor-acceptor emitter based nonsymmetrical connection for organic emitting diodes with improving exciton utilization. RSC Adv 2020; 10:4002-4013. [PMID: 35492665 PMCID: PMC9049240 DOI: 10.1039/c9ra10513a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 01/13/2020] [Indexed: 02/06/2023] Open
Abstract
A new strategy developed to construct blue emissive materials having an unsymmetrical connection with identical conjugated phenanthrimidazole groups results in the separation of the frontier orbitals and leads to donor-acceptor (D-A) architecture. The blue device with 2-(naphthalen-1-yl)-1-(4-(1-(naphthalen-1-yl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (p-PPI)/2-(naphthalen-1-yl)-1-(3-(1-(naphthalen-1-yl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (m-PPI) emissive layer (λ EL - 434/420 nm) shows high efficiencies: current efficiency (η c) - 5.83/3.56 cd A-1; power efficiency (η p) - 5.73/3.48 lm W-1; external quantum efficiency (η ex) - 8.98/6.48% at 3.0 V. Their cyano derivatives, p-CNPPI/m-CNPPI (λ EL - 422/406 nm) exhibit maximum efficiencies (η c - 6.28/4.38 cd A-1; η p - 6.14/4.01 lm W-1; η ex - 9.01/6.72%) at 2.9 V compared to the p-PPI/m-PPI devices. The weak charge transfer in the D-A emitters results in deep blue emission. The anisotropic structural characteristics of p-PPI, p-CNPPI, m-PPI and m-CNPPI induced horizontal dipole orientation in films and enhanced EL efficiency. These bipolar materials with suitable triplet energy can be used as hosts in green as well as red phosphorescent organic light emitting devices (PHOLEDs). The green/red device (λ EL - 504/618 nm) with p-CNPPI: Ir(ppy)3/Ir(MDQ)2 (acac) exhibits a maximum L - 8823/38418 cd m-2; η ex - 24.56/17.31%; η c - 84.30/18.09 cd A -1; η p - 86.43/21.43 lm W -1with CIE (0.33, 0.61)/(0.65, 0.34).
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Material Science Lab, Annamalai University Annamalai Nagar Tamilnadu-608 002 India
| | | | - Venugopal Thanikachalam
- Department of Chemistry, Material Science Lab, Annamalai University Annamalai Nagar Tamilnadu-608 002 India
| | - Sekar Sivaraj
- Department of Chemistry, Material Science Lab, Annamalai University Annamalai Nagar Tamilnadu-608 002 India
| | - Annadurai Prabhakaran
- Department of Chemistry, Material Science Lab, Annamalai University Annamalai Nagar Tamilnadu-608 002 India
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Jayabharathi J, Panimozhi S, Thanikachalam V. Asymmetrically twisted phenanthrimidazole derivatives as host materials for blue fluorescent, green and red phosphorescent OLEDs. Sci Rep 2019; 9:17555. [PMID: 31772249 PMCID: PMC6879643 DOI: 10.1038/s41598-019-54125-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 10/30/2019] [Indexed: 11/09/2022] Open
Abstract
The electroluminescent properties of asymmetrically twisted phenanthrimidazole derivatives comprised of fluorescent anthracene or pyrene unit namely, 1-(1-(anthracen-10-yl)naphthalen-4-yl)-2-styryl-1H-phenanthro[9,10-d]imidazole (ANSPI), 1-(1-(pyren-1-yl) naphthalene-4-yl)-2-styryl-1H-phenanthro[9,10-d]imidazole (PNSPI), 4-(2-(4-(anthracen-9-yl) styryl)-1H-phenanthro[9,10-d]imidazol-1-yl)naphthalene-1-carbonitrile (ASPINC) and 4-(2-(4-(pyren-1-yl)styryl)-1H-phenanthro[9,10-d]imidazol-1-yl)naphthalene-1-carbonitrile (PSPINC) for blue OLEDs have been analyzed. The asymmetrically twisted conformation interrupt π-conjugation effectively results in deep-blue emission. The pyrene containing PSPINC based non-doped blue device (476 nm) shows maximium efficiencies (current efficiency (ηc)-4.23 cd/A; power efficiency (ηp)-2.86 lm/W; external quantum efficiency (ηex)-3.48%: CIE (0.16, 0.17) at 3.10 V. Among the doped blue devices, An(PPI)2:ASPINC shows high efficiencies (ηc-12.13 cd/A; ηp-5.98 lm/W; ηex-6.79%; L-23986 cd m-2; EL-458 nm) at 3.15 V with CIE (0.15, 0.17) than An(PPI)2:PSPINC based device which is inconsistent with non-doped device performances. The green and red PhOLEDs show higher efficiencies with Ir(ppy)3: ASPINC (ηc-50.6 cd/A; ηp-53.4 lm/W; ηex-17.0%; L-61581 cd m-2; EL-501 nm, CIE (0.31, 0.60) at 3.32 V and (bt)2Ir(dipba): ASPINC (ηc-15.2 cd/A; ηp-16.5 lm/W; ηex-14.5%; L-13456 cd m-2; EL-610 nm), CIE (0.63, 0.36) at 3.20 V, respectively. The complete energy transfer between the host and dopant molecules improved the efficiency of PHOLEDs.
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Annamalai University, Annamalai nagar, 608 002, Tamilnadu, India.
| | - Sekar Panimozhi
- Department of Chemistry, Annamalai University, Annamalai nagar, 608 002, Tamilnadu, India
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Jayabharathi J, Nethaji P, Thanikachalam V, Ramya R. Derivatives of Cyanonaphthyl-Substituted Phenanthroimidazole as Blue Emitters for Nondoped Organic Light-Emitting Diodes. ACS OMEGA 2019; 4:4553-4570. [PMID: 31459647 PMCID: PMC6649183 DOI: 10.1021/acsomega.8b03617] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 02/13/2019] [Indexed: 06/10/2023]
Abstract
New multifunctional blue-emissive materials with superior thermal properties, viz., 4,4'-bis(1-(4-naphthyl)-1H-phenanthro[9,10-d]imidazol-2-yl)binaphthyl (NPIBN), 4,4'-bis(1-(4-cyanonaphthyl)-1H-phenanthro[9,10-d]imidazol-2-yl)biphenyl (CNPIBP), and 4,4'-bis(1-(4-cyanonaphthyl)-1H-phenanthro[9,10-d]imidazol-2-yl)binaphthyl (CNPIBN) have been synthesized. The said molecules show high photoluminescence quantum yield (Φs/f: NPIBN-0.75/0.68, CNPIBP-0.85/0.76, and CNPIBN-0.90/0.88). The fabricated nondoped/doped device with CNPIBN/4,4'-bis(carbazol-9-yl)biphenyl: CNPIBN display maximum efficiencies (ηex 4.96/5.4%; ηc 7.46/7.56 cd A-1; ηp 6.85/6.91 lm W-1) at low turn-on voltage (3.5/3.8 V). Nondoped devices based on D-π-A architecture, 4-(2-(5-(9H-carbazol-9-yl)thiophen-2-yl)-1H-phenanthro[9,10-d]imidazol-1-yl)naphthalene-1-carbonitrile exhibit maximum efficiencies (ηex 2.32%; ηc 4.00 cd A-1; ηp 3.42 lm W-1) compared to 4-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)-1H-phenanthro[9,10-d]imidazol-1-yl)naphthalene-1-carbonitrile (ηex 2.01%; ηc 3.89 cd A-1; ηp 3.15 lm W-1).
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Annamalai
University, Annamalai Nagar, Chidambaram, Tamilnadu 608 002, India
| | - Pavadai Nethaji
- Department of Chemistry, Annamalai
University, Annamalai Nagar, Chidambaram, Tamilnadu 608 002, India
| | - Venugopal Thanikachalam
- Department of Chemistry, Annamalai
University, Annamalai Nagar, Chidambaram, Tamilnadu 608 002, India
| | - Ramaiyan Ramya
- Department of Chemistry, Annamalai
University, Annamalai Nagar, Chidambaram, Tamilnadu 608 002, India
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Hirai M, Tanaka N, Sakai M, Yamaguchi S. Structurally Constrained Boron-, Nitrogen-, Silicon-, and Phosphorus-Centered Polycyclic π-Conjugated Systems. Chem Rev 2019; 119:8291-8331. [DOI: 10.1021/acs.chemrev.8b00637] [Citation(s) in RCA: 286] [Impact Index Per Article: 57.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Masato Hirai
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
| | - Naoki Tanaka
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
| | - Mika Sakai
- Department of Chemistry, Graduate School of Science and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
| | - Shigehiro Yamaguchi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
- Department of Chemistry, Graduate School of Science and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
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Jayabharathi J, Thanikachalam V, Sundari GA. Efficient electroluminescent hybridized local and charge-transfer host materials with small singlet–triplet splitting to enhance exciton utilization efficiency: excited state transition configuration. RSC Adv 2019; 9:6658-6680. [PMID: 35518456 PMCID: PMC9060926 DOI: 10.1039/c9ra00135b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 02/18/2019] [Indexed: 01/08/2023] Open
Abstract
A series of efficient electroluminescent materials with dual carrier transport properties shows enhanced singlet exciton utilization (ηs) due to small singlet–triplet splitting (ΔEST). The strong orbital-coupling transitions of N-(4-(1-(1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-4,5-diphenyl-1H-imidazol-2-yl)naphthalen-4-yl)phenyl)-N-phenyl benzenamine (DDPB) exhibit deep blue emission at 435 nm (CIEy, 0.07) with an external quantum efficiency of 2.01%. The electroluminescent efficiencies of 2-(1-(9H-carbazol-9-yl)naphthalen-4-yl)-1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-1H-phenanthro[9,10-d]imidazole (CDDPI) (L – 3992 cd m−2; ηex – 3.01%; ηc – 2.56 cd A−1; ηp – 2.12 lm W−1) are higher than those of the N-(4-(1-(1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-H-phenanthro[9,10-d]imidazole-2-yl)naphthalen-4-yl)phenyl)-N-phenylbenzenamine (DBDPA) based device (L – 3015 cd m−2; ηex – 2.85%; ηc – 2.01 cd A−1; ηp – 1.92 lm W−1). The blue emissive materials CDDPI and DBDPA are used as a host to construct green and red phosphorescent OLEDs: the green device based on CDDPI:Ir(ppy)3 exhibits higher efficiencies (L – 8812 cd m−2; ηex – 19.0%; ηc – 27.5 cd A−1; ηp – 33.0 lm W−1) at 2.7 V and the red device based on CDDPI:Ir(MQ)2(acac) exhibits a maximum luminance of 39 661 cd m−2 with excellent EL efficiencies [ηex – 19.2%; ηc – 27.9 cd A−1; ηp – 29.2 lm W−1; CIE (0.64, 0.34)] compared with those of the DBDPA:Ir(MQ)2(acac) based device [L – 37 621 cd m−2; ηex – 18.5%; ηc – 25.2 cd A−1; ηp – 25.8 lm W−1; CIE (0.64, 0.34)]. CDDPI:Ir(ppy)3 exhibits higher efficiencies: L = 8812 cd m−2; ηex = 19.0%; ηc = 27.5 cd A−1; ηp = 33.0 lm W−1 at 2.7 V.![]()
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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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Jayabharathi J, Ramya R, Thanikachalam V, Jeeva P, Sarojpurani E. Efficient full-colour organic light-emitting diodes based on donor–acceptor electroluminescent materials with a reduced singlet–triplet splitting energy gap. RSC Adv 2019; 9:2948-2966. [PMID: 35518987 PMCID: PMC9060244 DOI: 10.1039/c8ra09486a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 12/21/2018] [Indexed: 12/13/2022] Open
Abstract
A series of efficient blue-emitting materials, namely, Cz-DPVI, Cz-DMPVI, Cz-DEPVI and TPA-DEPVI, possessing a donor–acceptor architecture with dual carrier transport properties and small singlet–triplet splitting is reported. These compounds exhibit excellent thermal properties with a very high glass-transition temperature (Tg), and thus, a stable uniform thin film was formed during device fabrication. Among the weak donor compounds, specifically, Cz-DPVI, Cz-DMPVI and Cz-DEPVI, the Cz-DEPVI-based device showed the maximum efficiencies (L: 13 955 cd m−2, ηex: 4.90%, ηc: 6.0 cd A−1, and ηp: 5.4 lm W−1) with CIE coordinates of (0.15, 0.06) at 2.8 V. The electroluminescent efficiencies of Cz-DEPVI were higher than that of the strong donor TPA-DEPVI-based device (L: 13 856 cd m−2, ηex: 4.70%, ηc: 5.7 cd A−1, and ηp: 5.2 lm W−1). Furthermore, these blue emissive materials were used as hosts to construct efficient green and red phosphorescent OLEDs. The green device based on Cz-DEPVI:Ir(ppy)3 exhibited the maximum L of 8891 cd m−2, ηex of 19.3%, ηc of 27.9 cd A−1 and ηp of 33.4 lm W−1 with CIE coordinates of (0.31, 0.60) and the red device based on Cz-DEPVI:Ir(MQ)2(acac) exhibited the maximum L of 40 565 cd m−2, ηex of 19.9%, ηc of 26.0 cd A−1 and ηp of 27.0 lm W−1 with CIE coordinates of (0.64, 0.37). The Cz-DEPVI device showed high efficiencies of L: 13955 cd m−2, ηex: 4.90%, ηc: 6.0 cd A−1, ηp: 5.4 lm W−1 and CIE coordinates of (0.15, 0.06) at 2.8 V.![]()
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Jayabharathi J, Sujatha P, Thanikachalam V, Nethaji P. Efficient donor-acceptor host materials for green organic light-emitting devices: non-doped blue-emissive materials with dual charge transport properties. RSC Adv 2018; 8:20007-20015. [PMID: 35541653 PMCID: PMC9080778 DOI: 10.1039/c8ra02840k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 05/15/2018] [Indexed: 12/02/2022] Open
Abstract
Comparative optical, electroluminescence and theoretical studies were performed for (E)-4'-(1-(4-(2-(1-(4-morpholinophenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)vinyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)-N,N-diphenyl-[1,1'-biphenyl]-4-amine (SMPI-TPA) and (E)-4-(4-(2-(4-(2-(4-(9H-carbazol-9-yl)phenyl)-1H-phenanthro[9,10-d]imidazol-1-yl)styryl)-1H-phenanthro[9,10-d]imidazol-1-yl)phenyl)morpholine (SMPI-Cz). These compounds show excellent thermal properties, dual charge transport properties and form thin films under thermal evaporation. Blue OLEDs (CIE: 0.16, 0.08) based on SMPI-TPA show efficient device performance (η ex 6.1%; η c 5.3 cd A-1; η p 5.2 lm W-1) at low turn-on voltages. Both SMPI-TPA and SMPI-Cz were utilised as hosts for green OLEDs. The devices with SMPI-Cz (30 nm):5 wt% Ir(ppy)3 exhibit maximum luminance of 20 725 cd m-2, and η c and η p values of 61.4 cd A-1 and 63.8 lm W-1, respectively. In comparison, devices with SMPI-TPA (30 nm):5 wt% Ir(ppy)3 exhibit high η c and η p values of 65.2 cd A-1 and 67.1 lm W-1, respectively. Maximum η ex values of 19.6% and 23.4% were obtained from SMPI-TPA:Ir(ppy)3 and SMPI-Cz:Ir(ppy)3, respectively. These device performances indicate that the phenanthroimidazole unit is a tunable building unit for efficient carrier injection and it may also be employed as a host for green OLEDs.
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Annamalai University Annamalainagar 608 002 Tamilnadu India +91 9443940735
| | - Palanisamy Sujatha
- Department of Chemistry, Annamalai University Annamalainagar 608 002 Tamilnadu India +91 9443940735
| | - Venugopal Thanikachalam
- Department of Chemistry, Annamalai University Annamalainagar 608 002 Tamilnadu India +91 9443940735
| | - Pavadai Nethaji
- Department of Chemistry, Annamalai University Annamalainagar 608 002 Tamilnadu India +91 9443940735
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Jayabharathi J, Ramya R, Thanikachalam V, Nethaji P. Optical and electroluminescent performances of dihydrobenzodioxin phenanthroimidazoles based blue-emitting materials. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.02.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Peng HN, Yu Y, Liu XH, Zheng J, Cheng H, Hu X. Synthesis and Properties of D–π–A Structural Imidazole-Triphenylamine Derivatives. JOURNAL OF CHEMICAL RESEARCH 2018. [DOI: 10.3184/174751918x15161933697790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Four novel D-π-A structural 1-aryl-2-[4-(N,N-diphenyl)phenyl]-4,5-diphenyl-1H-imidazoles have been synthesised. Their synthesis, thermal stability, optical properties and electrochemical behaviour have also been investigated. These compounds exhibit increased thermal stability, blue emissions and intramolecular charge transfer. The HOMO and LUMO energy levels of these compounds were calculated from electrochemical measurements.
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Affiliation(s)
- Hua-Nan Peng
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334001, PR China
| | - Ye Yu
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334001, PR China
| | - Xiao-Hui Liu
- College of Chemistry, Nanchang University, Nanchang 330031, PR China
| | - Jie Zheng
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334001, PR China
| | - Hao Cheng
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334001, PR China
| | - Xin Hu
- Key Laboratory of Applied Organic Chemistry, Higher Institutions of Jiangxi Province, Shangrao Normal University, Shangrao 334001, PR China
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Jayabharathi J, Ramya R, Thanikachalam V, Nethaji P. Tailoring the molecular design of twisted dihydrobenzodioxin phenanthroimidazole derivatives for non-doped blue organic light-emitting devices. RSC Adv 2018; 8:29031-29043. [PMID: 35548015 PMCID: PMC9084391 DOI: 10.1039/c8ra05004j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/30/2018] [Indexed: 11/21/2022] Open
Abstract
Three fused polycyclic aryl fragments, namely, naphthyl, methoxynaphthyl, and pyrenyl have been used to construct blue-emissive phenanthroimidazole-functionalized target molecules, i.e., 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(naphthalen-1-yl)-1H-phenanthro[9,10-d]imidazole (1), 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(1-methoxynaphthalen-4-yl)-1H-phenanthro[9,10-d]imidazole (2), and 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(pyren-10-yl)-1H-phenanthro[9,10-d]imidazole (3). The up-conversion of triplets to singlets via a triplet–triplet annihilation (TTA) process is dominant in these compounds due to 2ET1 > ES1. The pyrenyl dihydrobenzodioxin phenanthroimidazole (3)-based nondoped OLED exhibits blue emission (450 nm) with CIE (0.15, 0.14), a luminance of 53 890 cd m−2, power efficiency of 5.86 lm W−1, external quantum efficiency of 5.30%, and current efficiency of 6.90 cd A−1. The efficient device performance of pyrenyl dihydrobenzodioxin phenanthroimidazole is due to the TTA contribution to the electroluminescent process. Efficient blue emitters, 1-(2,3-dihydrobenzodioxinyl)-2-naphthylphenanthroimidazole, 1-(2,3-dihydrobenzodioxinyl)-2-methoxynaphthylphenanthroimidazole and 1-(2,3-dihydrobenzodioxinyl)-2-pyrenylphenanthroimidazole have been reported.![]()
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Varathan E, Subramanian V. The role of sulfur oxidation in controlling the electronic properties of sulfur-containing host molecules for phosphorescent organic light-emitting diodes. Phys Chem Chem Phys 2017; 19:12002-12012. [PMID: 28443899 DOI: 10.1039/c7cp00828g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this study a series of dibenzothiophene (DBT) derivatives having different valence states of sulfur atoms have been reported as host materials for blue phosphorescent organic light-emitting diodes. Their electronic properties have also been thoroughly investigated to develop structure-property relationships which include the consideration of the effect of various oxidation states of the sulfur atom in the core moiety and linking (C-N linkage) of subunits with the core at different positions. The results obtained from the electronic structure calculations highlight that the triplet energy (ET), singlet-triplet energy difference (ΔEST), reorganization energy for the hole and the injection barrier for the electron decrease with an increase in the oxidation state of the sulfur atom in DBT. On the other hand, the injection barrier for the hole and the reorganization energy for the electron increase upon increasing the oxidation state of the sulfur atom present in the DBT.
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Affiliation(s)
- E Varathan
- Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai-600 020, India.
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Jayabharathi J, Sujatha P, Thanikachalam V, Jeeva P, Nethaji P. Efficient non-doped blue organic light-emitting diodes: donor–acceptor type host materials. RSC Adv 2017. [DOI: 10.1039/c7ra11732a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Blue devices with phenanthroimidazole OMeNPI-PITPA show maximum efficiencies ηex 4.90%; ηc 5.90 cd A−1 and are used as hosts for green OLEDs.
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Kondrasenko I, Tsai ZH, Chung KY, Chen YT, Ershova YY, Doménech-Carbó A, Hung WY, Chou PT, Karttunen AJ, Koshevoy IO. Ambipolar Phosphine Derivatives to Attain True Blue OLEDs with 6.5% EQE. ACS APPLIED MATERIALS & INTERFACES 2016; 8:10968-10976. [PMID: 27100797 DOI: 10.1021/acsami.6b01041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A family of new branched phosphine derivatives {Ph2N-(C6H4)n-}3P → E (E = O 1-3, n = 1-3; E = S 4-6, n = 1-3; E = Se 7-9, n = 1-3; E = AuC6F5 4-6, n = 1-3), which are the donor-acceptor type molecules, exhibit efficient deep blue room temperature fluorescence (λem = 403-483 nm in CH2Cl2 solution, λem = 400-469 nm in the solid state). Fine tuning the emission characteristics can be achieved varying the length of aromatic oligophenylene bridge -(C6H4)n-. The pyramidal geometry of central R3P → E fragment on the one hand disrupts π-conjugation between the branches to preserve blue luminescence and high triplet energy, while on the other hand provides amorphous materials to prevent excimer formation and fluorescence self-quenching. Hence, compounds 2, 3, 5, and 12 were used as emitters to fabricate nondoped and doped electroluminescent devices. The luminophore 2 (E = O, n = 2) demonstrates excellently balanced bipolar charge transport and good nondoped device performance with a maximum external quantum efficiency (EQEmax) of 3.3% at 250 cd/m(2) and Commission International de L'Eclairage (CIE) coordinates of (0.15, 0.08). The doped device of 3 (E = O, n = 3) shows higher efficiency (EQEmax of 6.5, 6.0 at 100 cd/m(2)) and high color purity with CIE (0.15, 0.06) that matches the HDTV standard blue. The time-resolved electroluminescence measurement indicates that high efficiency of the device can be attributed to the triplet-triplet annihilation to enhance generation of singlet excitons.
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Affiliation(s)
- Ilya Kondrasenko
- University of Eastern Finland , Department of Chemistry, Joensuu 80101, Finland
| | - Zheng-Hua Tsai
- Institute of Optoelectronic Sciences, National Taiwan Ocean University , Keelung 20224, Taiwan
| | - Kun-You Chung
- National Taiwan University , Department of Chemistry, Taipei 10617, Taiwan
| | - Yi-Ting Chen
- Soochow University , Department of Chemistry, Lin-shih Rd. 70, Shih-Lin Taipei, TW 111, Taiwan
| | - Yana Yu Ershova
- University of Eastern Finland , Department of Chemistry, Joensuu 80101, Finland
| | | | - Wen-Yi Hung
- Institute of Optoelectronic Sciences, National Taiwan Ocean University , Keelung 20224, Taiwan
| | - Pi-Tai Chou
- National Taiwan University , Department of Chemistry, Taipei 10617, Taiwan
| | | | - Igor O Koshevoy
- University of Eastern Finland , Department of Chemistry, Joensuu 80101, Finland
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Jayabharathi J, Prabhakaran A, Thanikachalam V, Jeeva P. Efficient non-doped blue emitting devices based on bis(phenanthrimidazolyl)biphenyl derivatives. NEW J CHEM 2016. [DOI: 10.1039/c6nj02431a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Efficient non-doped blue emitting devices based on bis(phenanthrimidazolyl)biphenyl derivatives have been reported.
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Affiliation(s)
| | | | | | - Palanivel Jeeva
- Department of Chemistry
- Annamalai University
- Annamalainagar 608 002
- India
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Jayabharathi J, Prabhakaran A, Thanikachalam V, Sundharesan M. Highly efficient non-doped blue electroluminescent materials for organic light-emitting devices. RSC Adv 2016. [DOI: 10.1039/c6ra11439c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Three new born blue light emitting materials, 1-naphthalen-1-yl-, 4-methylnaphthalen-1-yl- and 4-methoxynaphthalen-1-yl- based phenanthro[9,10]imidazole-2-yl-1,1′-biphenyl derivatives through two step procedure using inexpensive catalysts.
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Liu JY, Hou XN, Tian Y, Jiang L, Deng S, Röder B, Ermilov EA. Photoinduced energy and charge transfer in a bis(triphenylamine)–BODIPY–C60 artificial photosynthetic system. RSC Adv 2016. [DOI: 10.1039/c6ra06841c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The bis(triphenylamine)–BODIPY–C60 artificial photosynthetic system has been prepared and studied for its photoinduced transfer processes in polar and nonpolar solvents using various steady-state and time-resolved spectroscopic techniques.
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Affiliation(s)
- Jian-Yong Liu
- State Key Laboratory of Photocatalysis on Energy and Environment & Fujian Engineering Research Center of Functional Materials
- College of Chemistry
- Fuzhou University
- Fuzhou 350002
- P. R. China
| | - Xue-Ni Hou
- State Key Laboratory of Photocatalysis on Energy and Environment & Fujian Engineering Research Center of Functional Materials
- College of Chemistry
- Fuzhou University
- Fuzhou 350002
- P. R. China
| | - Ye Tian
- State Key Laboratory of Photocatalysis on Energy and Environment & Fujian Engineering Research Center of Functional Materials
- College of Chemistry
- Fuzhou University
- Fuzhou 350002
- P. R. China
| | - Lizhi Jiang
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences Fuzhou
- Fujian 350002
- P. R. China
| | - Shuiquan Deng
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences Fuzhou
- Fujian 350002
- P. R. China
| | - Beate Röder
- Institut für Physik
- Photobiophysik
- Humboldt-Universität zu Berlin
- D-12489 Berlin
- Germany
| | - Eugeny A. Ermilov
- Institut für Physik
- Photobiophysik
- Humboldt-Universität zu Berlin
- D-12489 Berlin
- Germany
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Yang X, Zhou G, Wong WY. Functionalization of phosphorescent emitters and their host materials by main-group elements for phosphorescent organic light-emitting devices. Chem Soc Rev 2015; 44:8484-575. [PMID: 26245654 DOI: 10.1039/c5cs00424a] [Citation(s) in RCA: 398] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Phosphorescent organic light-emitting devices (OLEDs) have attracted increased attention from both academic and industrial communities due to their potential practical application in high-resolution full-color displays and energy-saving solid-state lightings. The performance of phosphorescent OLEDs is mainly limited by the phosphorescent transition metal complexes (such as iridium(III), platinum(II), gold(III), ruthenium(II), copper(I) and osmium(II) complexes, etc.) which can play a crucial role in furnishing efficient energy transfer, balanced charge injection/transporting character and high quantum efficiency in the devices. It has been shown that functionalized main-group element (such as boron, silicon, nitrogen, phosphorus, oxygen, sulfur and fluorine, etc.) moieties can be incorporated into phosphorescent emitters and their host materials to tune their triplet energies, frontier molecular orbital energies, charge injection/transporting behavior, photophysical properties and thermal stability and hence bring about highly efficient phosphorescent OLEDs. So, in this review, the recent advances in the phosphorescent emitters and their host materials functionalized with various main-group moieties will be introduced from the point of view of their structure-property relationship. The main emphasis lies on the important role played by the main-group element groups in addressing the key issues of both phosphorescent emitters and their host materials to fulfill high-performance phosphorescent OLEDs.
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Affiliation(s)
- Xiaolong Yang
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, State Key Laboratory for Mechanical Behavior of Materials, Department of Chemistry, Faculty of Science, Xi'an Jiaotong University, Xi'an 710049, P. R. China.
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Fan Z, Zhao H, Li N, Quan Y, Chen Q, Ye S, Li S, Wang Y, Fan Q, Huang W. Tuning Charge Balance in Solution-Processable Bipolar Triphenylamine-diazafluorene Host Materials for Phosphorescent Devices. ACS APPLIED MATERIALS & INTERFACES 2015; 7:9445-9452. [PMID: 25895904 DOI: 10.1021/am509014v] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Three bipolar hosts, namely TPA-DAF, TPA-DAF2, and TPA-DAF3, comprising an electron-donating triphenylamine (TPA) group and electron-accepting 4,5-diazafluorene (DAF) units are investigated for phosphorescent organic light-emitting diodes (PhOLEDs). Given the nonplanar structure of the sp(3)-hybridized C9 atom in DAF unit, these molecules have a highly nonplanar configuration, good film-forming property, and high triplet energy (ET) of 2.88-2.89 eV. Among them, TPA-DAF shows more balanced carrier injecting/transporting ability, suitable highest occupied molecular orbital (MO) energy level and higher current density, and therefore TPA-DAF-based devices exhibit the best performances, having an extremely slight efficiency roll-off with current efficiency of 20.0 cd/A at 973 cd/m(2), 19.5 cd/A at 5586 cd/m(2), and 17.6 cd/A at 9310 cd/m(2) for blue PhOLEDs; 23.5 cd/A at 1059 cd/m(2) and 15.3 cd/A at 8850 cd/m(2) for green PhOLEDs; and 12.2 cd/A at 1526 cd/m(2), 10.5 cd/A at 5995 cd/m(2), and 9.2 cd/A at 8882 cd/m(2) for red PhOLEDs, respectively. The results also provide a direct proof for the influence of charge balance on the device performance.
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Affiliation(s)
| | | | | | | | | | | | | | - Ying Wang
- #Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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Jiang W, Cui P, Ban X, Sun Y. Bis(phosphine oxide)/triphenylamine based material for solution-processed blue electrofluorescent and green electrophosphorescent devices. RSC Adv 2015. [DOI: 10.1039/c5ra07730c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A novel multifunctional material TPA-BPhPO has been designed and synthesized to explore its use as the blue emitter and the host material for solution-processed blue electrofluorescent and green electrophosphorescent devices.
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Affiliation(s)
- Wei Jiang
- School of Chemistry and Chemical Engineering
- Southeast University
- Nanjing
- PR China
| | - Peng Cui
- School of Chemistry and Chemical Engineering
- Southeast University
- Nanjing
- PR China
| | - Xinxin Ban
- School of Chemistry and Chemical Engineering
- Southeast University
- Nanjing
- PR China
| | - Yueming Sun
- School of Chemistry and Chemical Engineering
- Southeast University
- Nanjing
- PR China
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Zhang Z, Zhang Z, Ye K, Zhang J, Zhang H, Wang Y. Diboron complexes with bis-spiro structures as high-performance blue emitters for OLEDs. Dalton Trans 2015. [DOI: 10.1039/c5dt02093j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By using blue-emissive diboron complexes with bis-spiro structures as emitting layers, the most efficient blue OLEDs based on four-coordinate organoboron compounds have been achieved.
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Affiliation(s)
- Zhenyu Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
| | - Zuolun Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
| | - Kaiqi Ye
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
| | - Jingying Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
| | - Hongyu Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
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Jayabharathi J, Ramanathan P, Thanikachalam V. Synthesis and optical properties of phenanthromidazole derivatives for organic electroluminescent devices. NEW J CHEM 2015. [DOI: 10.1039/c4nj01515k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The external quantum efficiency roll-off may be due to triplet–triplet annihilation (TTA) and triplet–polaron annihilation (TPA).
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Wang XX, Tao T, Geng J, Ma BB, Peng YX, Huang W. Dipyrido[3,2-a:2′,3′-c]phenazine-Based Donor-Acceptor Aromatic Heterocyclic Compounds with Thienyl and Triphenylamino Chromophores at the 2,7- and/or 10,13-Positions. Chem Asian J 2013; 9:514-25. [DOI: 10.1002/asia.201301284] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Indexed: 01/15/2023]
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Wu J, Wu SX, Wu Y, Kan YH, Geng Y, Su ZM. Quantum chemical characterization and design of host materials based on phosphine oxide-substituted (triphenylamine) fluorene for (deep) blue phosphors in OLEDs. Phys Chem Chem Phys 2013; 15:2351-9. [DOI: 10.1039/c2cp42958f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Carrier injection and transport in blue phosphorescent organic light-emitting device with oxadiazole host. Int J Mol Sci 2012; 13:7575-7585. [PMID: 22837713 PMCID: PMC3397545 DOI: 10.3390/ijms13067575] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/25/2012] [Accepted: 06/13/2012] [Indexed: 11/17/2022] Open
Abstract
In this paper, we investigate the carrier injection and transport characteristics in iridium(III)bis[4,6-(di-fluorophenyl)-pyridinato-N,C2′]picolinate (FIrpic) doped phosphorescent organic light-emitting devices (OLEDs) with oxadiazole (OXD) as the bipolar host material of the emitting layer (EML). When doping Firpic inside the OXD, the driving voltage of OLEDs greatly decreases because FIrpic dopants facilitate electron injection and electron transport from the electron-transporting layer (ETL) into the EML. With increasing dopant concentration, the recombination zone shifts toward the anode side, analyzed with electroluminescence (EL) spectra. Besides, EL redshifts were also observed with increasing driving voltage, which means the electron mobility is more sensitive to the electric field than the hole mobility. To further investigate carrier injection and transport characteristics, FIrpic was intentionally undoped at different positions inside the EML. When FIrpic was undoped close to the ETL, driving voltage increased significantly which proves the dopant-assisted-electron-injection characteristic in this OLED. When the undoped layer is near the electron blocking layer, the driving voltage is only slightly increased, but the current efficiency is greatly reduced because the main recombination zone was undoped. However, non-negligible FIrpic emission is still observed which means the recombination zone penetrates inside the EML due to certain hole-transporting characteristics of the OXD.
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Fan C, Zhao F, Gan P, Yang S, Liu T, Zhong C, Ma D, Qin J, Yang C. Simple Bipolar Molecules Constructed from Biphenyl Moieties as Host Materials for Deep-Blue Phosphorescent Organic Light-Emitting Diodes. Chemistry 2012; 18:5510-4. [DOI: 10.1002/chem.201103703] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Indexed: 11/06/2022]
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Wu J, Liao Y, Wu SX, Li HB, Su ZM. Phenylcarbazole and phosphine oxide/sulfide hybrids as host materials for blue phosphors: effectively tuning the charge injection property without influencing the triplet energy. Phys Chem Chem Phys 2012; 14:1685-93. [DOI: 10.1039/c2cp23418a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Lee CC, Leung MK, Lee PY, Chiu TL, Lee JH, Liu C, Chou PT. Synthesis and Properties of Oxygen-Linked N-Phenylcarbazole Dendrimers. Macromolecules 2011. [DOI: 10.1021/ma202433y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | | | - Pei-Yu Lee
- Department of Photonics Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
| | - Tien-Lung Chiu
- Department of Photonics Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
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Tao Y, Yang C, Qin J. Organic host materials for phosphorescent organic light-emitting diodes. Chem Soc Rev 2011; 40:2943-70. [PMID: 21369622 DOI: 10.1039/c0cs00160k] [Citation(s) in RCA: 564] [Impact Index Per Article: 43.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Phosphorescent organic light-emitting diodes (PhOLEDs) unfurl a bright future for the next generation of flat-panel displays and lighting sources due to their merit of high quantum efficiency compared with fluorescent OLEDs. This critical review focuses on small-molecular organic host materials as triplet guest emitters in PhOLEDs. At first, some typical hole and electron transport materials used in OLEDs are briefly introduced. Then the hole transport-type, electron transport-type, bipolar transport host materials and the pure-hydrocarbon compounds are comprehensively presented. The molecular design concept, molecular structures and physical properties such as triplet energy, HOMO/LUMO energy levels, thermal and morphological stabilities, and the applications of host materials in PhOLEDs are reviewed (152 references).
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Affiliation(s)
- Youtian Tao
- Department of Chemistry, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People's Republic of China
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Wang Z, Lu P, Chen S, Gao Z, Shen F, Zhang W, Xu Y, Kwok HS, Ma Y. Phenanthro[9,10-d]imidazole as a new building block for blue light emitting materials. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10321k] [Citation(s) in RCA: 211] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ye H, Zhao B, Liu M, Zhou X, Li Y, Li D, Su SJ, Yang W, Cao Y. Dual-functional conjugated polymers based on trifluoren-2-yl-amine for RGB organic light-emitting diodes. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm13533c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gong S, Chen Y, Zhang X, Cai P, Zhong C, Ma D, Qin J, Yang C. High-performance blue and green electrophosphorescence achieved by using carbazole-containing bipolar tetraarylsilanes as host materials. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11208b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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