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Kumar K, Thakur D, Karmakar A, Patra S, Kumar A, Banik S, Ghosh S. Indolo[3,2- a]carbazoles as Engineered Materials for Optoelectronic Applications: Synthesis, Structural Insights, and Computational Screening. J Org Chem 2024. [PMID: 38754107 DOI: 10.1021/acs.joc.3c02561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
The biological and medicinal importance of indolocarbazoles has been known for the past several decades. However, in recent times, these compounds have been emerging as potential candidates for optoelectronic applications, although several challenges are associated with their synthesis. We report here a Pd(II)-catalyzed process for the synthesis of indolo[3,2-a]carbazoles. The reaction proceeded under neat conditions and in the presence of aqueous nonmetallic oxidant TBHP, and the products were purified directly after the completion of the reaction. Also, the possibility of employing the present method for reaction with gram-scale feed was investigated. A detailed single-crystal analysis of several indolo[3,2-a]carbazoles revealed how the molecular arrangement can be tuned by altering the functionalization. Finally, the developed molecules were screened computationally to assess their potential for possible use as hole transport materials (HTMs) for organic light-emitting diodes (OLEDs).
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Affiliation(s)
- Krishan Kumar
- School of Chemical Sciences, IIT Mandi, Himachal Pradesh, Mandi 175005, India
| | - Diksha Thakur
- School of Chemical Sciences, IIT Mandi, Himachal Pradesh, Mandi 175005, India
| | - Anirban Karmakar
- Centro de Química Estrutural, Instituto Superior Técnico, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Subhendu Patra
- School of Chemical Sciences, IIT Mandi, Himachal Pradesh, Mandi 175005, India
| | - Arun Kumar
- School of Chemical Sciences, IIT Mandi, Himachal Pradesh, Mandi 175005, India
| | - Subrata Banik
- Department of Chemistry, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401, Tamil Nadu, India
| | - Subrata Ghosh
- School of Chemical Sciences, IIT Mandi, Himachal Pradesh, Mandi 175005, India
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2
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Wan F, Wang H, Gu Y, Fan G, Hou S, Yu J, Wang M, He F, Tian L. Bromine Substitution Improves the Photothermal Performance of π-Conjugated Phototheranostic Molecules. Chemistry 2024; 30:e202303502. [PMID: 37915302 DOI: 10.1002/chem.202303502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/03/2023]
Abstract
NIR-II fluorescence imaging-guided photothermal therapy (PTT) has been widely investigated due to its great application potential in tumor theranostics. PTT is an effective and non-invasive tumor treatment method that can adapt to tumor hypoxia; nevertheless, simple and effective strategies are still desired to develop new materials with excellent PTT properties to meet clinical requirements. In this work, we developed a bromine-substitution strategy to enhance the PTT of A-D-A'-D-A π-conjugated molecules. The experimental results reveal that bromine substitution can notably enhance the absorptivity (ϵ) and photothermal conversion efficiency (PCE) of the π-conjugated molecules, resulting in the brominated molecules generating two times more heat (ϵ808 nm ×PCE) than their unsubstituted counterpart. We disclose that the enhanced photothermal properties of bromine-substituted π-conjugated molecules are a combined outcome of the heavy-atom effect, enhanced ICT effect, and more intense bromine-mediate intermolecular π-π stacking. Finally, the NIR-II tumor imaging capability and efficient PTT tumor ablation of the brominated π-conjugated materials demonstrate that bromine substitution is a promising strategy for developing future high-performance NIR-II imaging-guided PTT agents.
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Affiliation(s)
- Feiyan Wan
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Huan Wang
- Shenzhen Grubbs Institute, Guangdong Provincial Key Laboratory of Catalysis and, Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Ying Gu
- Shenzhen Grubbs Institute, Guangdong Provincial Key Laboratory of Catalysis and, Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Guilin Fan
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Shengxin Hou
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Jiantao Yu
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Mengying Wang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Feng He
- Shenzhen Grubbs Institute, Guangdong Provincial Key Laboratory of Catalysis and, Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
| | - Leilei Tian
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China
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3
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O’Mari O, Vullev VI. Optical Window to Polarity of Electrolyte Solutions. Molecules 2023; 28:4360. [PMID: 37298836 PMCID: PMC10254283 DOI: 10.3390/molecules28114360] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/21/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
Medium polarity plays a crucial role in charge-transfer processes and electrochemistry. The added supporting electrolyte in electrochemical setups, essential for attaining the needed electrical conductivity, sets challenges for estimating medium polarity. Herein, we resort to Lippert-Mataga-Ooshika (LMO) formalism for estimating the Onsager polarity of electrolyte organic solutions pertinent to electrochemical analysis. An amine derivative of 1,8-naphthalimide proves to be an appropriate photoprobe for LMO analysis. An increase in electrolyte concentration enhances the polarity of the solutions. This effect becomes especially pronounced for low-polarity solvents. Adding 100 mM tetrabutylammonium hexafluorophosphate to chloroform results in solution polarity exceeding that of neat dichloromethane and 1,2-dichloroethane. Conversely, the observed polarity enhancement that emerges upon the same electrolyte addition to solvents such as acetonitrile and N,N-dimethylformamide is hardly as dramatic. Measured refractive indices provide a means for converting Onsager to Born polarity, which is essential for analyzing medium effects on electrochemical trends. This study demonstrates a robust optical means, encompassing steady-state spectroscopy and refractometry, for characterizing solution properties important for charge-transfer science and electrochemistry.
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Affiliation(s)
- Omar O’Mari
- Department of Bioengineering, University of California, Riverside, CA 92521, USA;
| | - Valentine I. Vullev
- Department of Bioengineering, University of California, Riverside, CA 92521, USA;
- Department of Chemistry, University of California, Riverside, CA 92521, USA
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
- Material Science and Engineering Program, University of California, Riverside, CA 92521, USA
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4
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Pfeifer L, Hoang NV, Crespi S, Pshenichnikov MS, Feringa BL. Dual-function artificial molecular motors performing rotation and photoluminescence. SCIENCE ADVANCES 2022; 8:eadd0410. [PMID: 36332022 PMCID: PMC9635830 DOI: 10.1126/sciadv.add0410] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Molecular machines have caused one of the greatest paradigm shifts in chemistry, and by powering artificial mechanical molecular systems and enabling autonomous motion, they are expected to be at the heart of exciting new technologies. One of the biggest challenges that still needs to be addressed is designing the involved molecules to combine different orthogonally controllable functions. Here, we present a prototype of artificial molecular motors exhibiting the dual function of rotary motion and photoluminescence. Both properties are controlled by light of different wavelengths or by exploiting motors' outstanding two-photon absorption properties using low-intensity near-infrared light. This provides a noninvasive way to both locate and operate these motors in situ, essential for the application of molecular machines in complex (bio)environments.
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Affiliation(s)
- Lukas Pfeifer
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
| | - Nong V. Hoang
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
| | - Stefano Crespi
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
| | - Maxim S. Pshenichnikov
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
| | - Ben L. Feringa
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands
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5
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Sudyoadsuk T, Funchien P, Petdee S, Loythaworn T, Chasing P, Waengdongbung W, Saenubol A, Hadsadee S, Jungsuttiwong S, Promarak V. Benzothiadiazole-based fluorophores as efficient non-doped emitters for solution-processed organic light-emitting diodes. NEW J CHEM 2022. [DOI: 10.1039/d2nj04354h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
New HLCT fluorophores are synthesized and successfully applied as non-doped emissive layers in solution-processed double-layered OLEDs. These devices exhibit intense yellow-green emission colors with superior performance.
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Affiliation(s)
- Taweesak Sudyoadsuk
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Patteera Funchien
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Sujinda Petdee
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Thidarat Loythaworn
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Pongsakorn Chasing
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Wijitra Waengdongbung
- Research Network of NANOTEC-VISTEC on Nanotechnology for Energy, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Atthapon Saenubol
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
| | - Sarinya Hadsadee
- Department of Chemistry, Faculty of Science, Ubon Ratchathani University, Warinchumrap, Ubon Ratchathani 34190, Thailand
| | - Siriporn Jungsuttiwong
- Department of Chemistry, Faculty of Science, Ubon Ratchathani University, Warinchumrap, Ubon Ratchathani 34190, Thailand
| | - Vinich Promarak
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
- Research Network of NANOTEC-VISTEC on Nanotechnology for Energy, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan, Rayong 21210, Thailand
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6
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Usta H, Cosut B, Alkan F. Understanding and Tailoring Excited State Properties in Solution-Processable Oligo( p-phenyleneethynylene)s: Highly Fluorescent Hybridized Local and Charge Transfer Character via Experiment and Theory. J Phys Chem B 2021; 125:11717-11731. [PMID: 34644090 DOI: 10.1021/acs.jpcb.1c07165] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Rod-shaped oligo(p-phenyleneethynylene) (OPE) offers an attractive π-framework for the development of solution-processable highly fluorescent molecules having tunable hybridized local and charge transfer (HLCT) excited states and (reverse) intersystem crossing ((R)ISC) channels. Herein, an HLCT oligo(p-phenyleneethynylene) library was studied for the first time in the literature in detail systematically via experiment and theory. The design, synthesis, and full characterization of a new highly fluorescent (ΦPL-solution ∼ 1) sky blue emissive 4',4‴-((2,5-bis((2-ethylhexyl)oxy)-1,4-phenylene)bis(ethyne-2,1-diyl))bis(N,N-diphenyl-[1,1'-biphenyl]-4-amine) (2EHO-TPA-PE) was also reported. The new molecule consists of a D'-Ar-π-D-π-Ar-D' molecular architecture with an extended π-spacer and no acceptor unit, and detailed structural, physicochemical, single-crystal, and optoelectronic characterizations were performed. A high solid-state quantum efficiency (ΦPL-solid state ∼ 0.8) was achieved as a result of suppressed exciton-phonon/vibronic couplings (no π-π interactions and multiple (14 per dimeric form) strong C-H···π interactions). Strong solution-phase/solid-state dipole-dependent tunable excited state behavior (local excited (LE) → HLCT → charge transfer (CT)) and decay dynamics covering a wide spectral region were demonstrated, and the CT state was observed to be highly fluorescent despite extremely large Stokes shift (∼130 nm)/fwhm (∼125 nm) and significant charge separation (0.75 charge·nm). Employing the Lippert-Mataga model, along with detailed photophysical studies and TDDFT calculations, key relationships between molecular design-electronic structure-exciton characteristics were elucidated with regards to HLCT and hot exciton channel formations. The interstate coupling between CT and LE states and the interplay of this coupling with respect to medium polarity were explored. A key relationship between excited-state symmetry breaking process and the formation of HLCT state was discussed for TPA-ended rod-shaped OPE π-systems. (R)ISC-related delayed fluorescence (τ ∼ 2-6 ns) processes were evident following the prompt decays (∼0.4-0.9 ns) both in the solution and in the solid-state. As a unique observation, the delayed fluorescence could be tuned and facilitated via small dielectric changes in the medium. Our results and the molecular engineering perspectives presented in this study may provide unique insights into the structural and electronic factors governing tunable excited state and hot-exciton channel formations in OPEs for (un)conventional solution-processed luminescence applications.
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Affiliation(s)
- Hakan Usta
- Department of Nanotechnology Engineering, Abdullah Gül University, 38080 Kayseri, Turkey
| | - Bunyemin Cosut
- Department of Chemistry, Gebze Technical University, 41400 Gebze, Kocaeli, Turkey
| | - Fahri Alkan
- Department of Nanotechnology Engineering, Abdullah Gül University, 38080 Kayseri, Turkey
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7
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Rodrigues NDN, Woolley JM, Krokidi KM, Tesa-Serrate MA, Turner MAP, Hine NDM, Stavros VG. Effects of substituent position on aminobenzoate relaxation pathways in solution. Phys Chem Chem Phys 2021; 23:23242-23255. [PMID: 34632473 DOI: 10.1039/d1cp03759e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The negative effects of ultraviolet radiation (UVR) on human skin have led to the widespread use of sunscreens, i.e. skincare products containing UV filters to absorb, reflect or otherwise block UVR. The mechanisms by which UV filters dissipate energy following photoexcitation, i.e. their photodynamics, can crucially determine a molecule's performance as a sunscreen UV filter. In this work, we evaluate the effects of substituent position on the in-solution relaxation pathways of two derivates of methyl anthranilate (an ortho compound that is a precursor to the UV filter meradimate), meta- and para-methyl anthranilate, m-MA and p-MA, respectively. The photodynamics of m-MA were found to be sensitive to solvent polarity: its emission spectra show larger Stokes shifts with increasing polarity, and both the fluorescence quantum yield and lifetimes for m-MA increase in polar solvents. While the Stokes shifts for p-MA are much milder and more independent of solvent environment than those of m-MA, we find its fluorescence quantum yields to be sensitive not only to solvent polarity but to the hydrogen bonding character of the solvent. In both cases (m- and p-MA) we have found common computational methods to be insufficient to appropriately model the observed spectroscopic data, likely due to an inability to account for explicit solvent interactions, a known challenge in computational chemistry. Therefore, apart from providing insight into the photodynamics of anthranilate derivatives, the work presented here also provides a case study that may be of use to theoretical chemists looking to improve and develop explicit solvent computational methods.
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Affiliation(s)
- Natércia D N Rodrigues
- University of Warwick, Department of Chemistry, Coventry, CV4 7AL, UK. .,Lipotec SAU, Calle Isaac Peral, 17 Pol. Ind. Camí Ral, 08850 Barcelona, Spain
| | - Jack M Woolley
- University of Warwick, Department of Chemistry, Coventry, CV4 7AL, UK.
| | | | | | - Matthew A P Turner
- University of Warwick, Department of Chemistry, Coventry, CV4 7AL, UK. .,University of Warwick, Department of Physics, Coventry, CV4 7AL, UK
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8
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Sun G, Wang XH, Li J, Yang BT, Gao Y, Geng Y. Effect of hybridized local and charge transfer molecules rotation in excited state on exciton utilization. Sci Rep 2021; 11:17686. [PMID: 34480055 PMCID: PMC8417272 DOI: 10.1038/s41598-021-97229-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/23/2021] [Indexed: 11/09/2022] Open
Abstract
The fluorescent molecules utilizing hybridized local and charge-transfer (HLCT) state as potential organic light-emitting diodes materials attract extensive attention due to their high exciton utilization. In this work, we have performed the density functional theory method on three HLCT-state molecules to investigate their excited-state potential energy surface (PES). The calculated results indicate the T1 and T2 energy gap is quite large, and the T2 is very close to S1 in the energy level. The large gap is beneficial for inhibiting the internal conversion between T1 and T2, and quite closed S1 and T2 energies are favor for activating the T2 → S1 reverse intersystem crossing path. However, considering the singlet excited-state PES by twisting the triphenylamine (TPA) or diphenylamine (PA) group, it can be found that the TPA or PA group almost has no influence on T1 and T2 energy levels. However, the plots of S1 PES display two kinds of results that the S1 emissive state is dominated by charge-transfer (CT) or HLCT state. The CT emission state formation would decrease the S1 energy level, enlarge the S1 and T2 gap, and impair the triplet exciton utilization. Therefore, understanding the relationship between the S1 PES and molecular structures is important for designing high-performance luminescent materials utilizing HLCT state.
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Affiliation(s)
- Gang Sun
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Xin-Hui Wang
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Jing Li
- College of Science, Beihua University, Jilin, 132013, People's Republic of China
| | - Bo-Ting Yang
- College of Science, Beihua University, Jilin, 132013, People's Republic of China.
| | - Ying Gao
- Jilin Provincial Key Laboratory of Straw-Based Functional Materials, Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun, 130052, People's Republic of China.
| | - Yun Geng
- Faculty of Chemistry, Northeast Normal University, Changchun, 130024, People's Republic of China
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9
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Savchuk MI, Kopchuk DS, Taniya OS, Nikonov IL, Egorov IN, Santra S, Zyryanov GV, Chupakhin ON, Charushin VN. 5-Aryl-6-arylthio-2,2'-bipyridine and 6-Arylthio-2,5-diarylpyridine Fluorophores: Pot, Atom, Step Economic (PASE) Synthesis and Photophysical Studies. J Fluoresc 2021; 31:1099-1111. [PMID: 33966136 DOI: 10.1007/s10895-021-02714-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 03/03/2021] [Indexed: 11/29/2022]
Abstract
A PASE (pot, step, atom, economic) synthetic approach to 5-aryl-6-arylthio-2,2'-bipyridine and 6-arylthio-2,5-diarylpyridine ligands/fluorophores has been reported via SNH in 6-aryl-5H-1,2,4-triazines/aza-Diels-Alder reaction sequence. In this article, the "1,2,4-triazine" methodology was successfully used for the synthesis of C6-thiophenol-substituted (2,2'-bi)pyridines as it is well known that thio-substituted (bi)pyridines and their aza-analogs are of wide practical interest. The photophysical properties of the obtained compounds are studied and compared with those reported earlier for 6-substituted 2,2'-bipyridines. The influence of the nature of substituents in the 6-arylthio(bi)pyridine core on the photophysical properties is discussed. It was observed that the new compounds exhibited promising photophysical properties and could be considered as potential push-pull fluorophores. In addition, they demonstrated greater Stokes shift values compared to the previously described 6-H, 6-arylamino and 6-pentafluoro-2,2'-bipyridines and higher fluorescence quantum yields values compare to pentafluorophenyl-substituted 2,2'-bipyridines. Depending on a nature of (bi)pyridine fluorophore LE (locally excited) and/or ICT (intramolecular charge transfer) state were prevailing in emission spectra.
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Affiliation(s)
- Maria I Savchuk
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Dmitry S Kopchuk
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Olga S Taniya
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Igor L Nikonov
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Ilya N Egorov
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002
| | - Sougata Santra
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.
| | - Grigory V Zyryanov
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Oleg N Chupakhin
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
| | - Valery N Charushin
- Ural Federal University, 19, Mira St, Yekaterinburg, Russian Federation, 620002.,Postovsky Institute of Organic Synthesis of RAS (Ural Division), 22/20, S. Kovalevskoy/Akademicheskaya St, Yekaterinburg, Russian Federation, 620990
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10
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Wang K, Jin L, Gao Y, Liang A, Finkenauer BP, Zhao W, Wei Z, Zhu C, Guo TF, Huang L, Dou L. Lead-Free Organic-Perovskite Hybrid Quantum Wells for Highly Stable Light-Emitting Diodes. ACS NANO 2021; 15:6316-6325. [PMID: 33709710 DOI: 10.1021/acsnano.1c00872] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two-dimensional perovskites that could be regarded as natural organic-inorganic hybrid quantum wells (HQWs) are promising for light-emitting diode (LED) applications. High photoluminescence quantum efficiencies (approaching 80%) and extremely narrow emission bandwidth (less than 20 nm) have been demonstrated in their single crystals; however, a reliable electrically driven LED device has not been realized owing to inefficient charge injection and extremely poor stability. Furthermore, the use of toxic lead raises concerns. Here, we report Sn(II)-based organic-perovskite HQWs employing molecularly tailored organic semiconducting barrier layers for efficient and stable LEDs. Utilizing femtosecond transient absorption spectroscopy, we demonstrate the energy transfer from organic barrier to inorganic perovskite emitter occurs faster than the intramolecular charge transfer in the organic layer. Consequently, this process allows efficient conversion of lower-energy emission associated with the organic layer into higher-energy emission from the perovskite layer. This greatly broadened the candidate pool for the organic layer. Incorporating a bulky small bandgap organic barrier in the HQW, charge transport is enhanced and ion migration is greatly suppressed. We demonstrate a HQW-LED device with pure red emission, a maximum luminance of 3466 cd m-2, a peak external quantum efficiency up to 3.33%, and an operational stability of over 150 h, which are significantly better than previously reported lead-free perovskite LEDs.
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Affiliation(s)
- Kang Wang
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Linrui Jin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yao Gao
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Aihui Liang
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, People's Republic of China
| | - Blake P Finkenauer
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Wenchao Zhao
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Zitang Wei
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Chenhui Zhu
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Tzung-Fang Guo
- Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Libai Huang
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Letian Dou
- Davidson School of Chemical Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
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11
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Wang Q, Sui N, Gao X, Chi X, Pan L, Lu R, Zhang H, Kang Z, Zhao B, Wang Y. Study of the Photoluminescence Characteristics of 4,4'-((1 E,1' E)-Quinoxaline-2,3-diylbis(ethene-2,1-diyl))bis( N, N-dimethylaniline). J Phys Chem B 2021; 125:4132-4140. [PMID: 33853330 DOI: 10.1021/acs.jpcb.1c00655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A comparative investigation on the photophysical properties of a quinoxaline derivative 4,4'-((1E,1'E)-quinoxaline-2,3-diylbis(ethene-2,1-diyl))bis(N,N-dimethylaniline) (QDMA2) was performed by employing many spectroscopies. Based on the pump-dump/push-probe measurement, it is found that a solvent-stabilized charge-transfer state can participate in the relaxation of excited QDMA2 with increasing solvent polarity. Meanwhile, the aggregated QDMA2 molecules were engineered into the organic light-emitting diode test, which showed a correlated color temperature value of 1875 K. With the help of a diamond anvil cell, the pressure-dependent photoluminescence of aggregated QDMA2 shows that the intermolecular interaction can affect the color and intensity of photoluminescence through adjusting the band gap and irradiative channel of the aggregated molecules. These results are important for understanding the structure-property relationships and the rational design of functional materials for optoelectronic applications.
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Affiliation(s)
- Quan Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Ning Sui
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Xiujun Gao
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Xiaochun Chi
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Lingyun Pan
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Ran Lu
- College of Chemistry, Jilin University, Changchun 130012, P. R. China
| | - Hanzhuang Zhang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Zhihui Kang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Bing Zhao
- State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, P. R. China
| | - Yinghui Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
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12
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Sabek HAZ, Alazaly AMM, Salah D, Abdel-Samad HS, Ismail MA, Abdel-Shafi AA. Photophysical properties and fluorosolvatochromism of D-π-A thiophene based derivatives. RSC Adv 2020; 10:43459-43471. [PMID: 35519720 PMCID: PMC9058427 DOI: 10.1039/d0ra08433f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/24/2020] [Indexed: 12/31/2022] Open
Abstract
Solvation-dependent photophysical properties of two push-pull thiophene-based compounds with donor-π-acceptor (D-π-A) structures were investigated using absorption, fluorescence emission and time resolved spectroscopy, and supported by different solvation models. Intramolecular charge transfer characteristics of the structurally similar 2-fluoro-4-(5-(4-methoxyphenyl)thiophen-2-yl)benzonitrile (MOT) and 4-(5-(4-(dimethylamino)phenyl)thiophen-2-yl)-2-fluorobenzonitrile (DMAT) were investigated. Significant enhancement of intramolecular charge transfer strength has been observed through molecular structure modification of the electron donating group from a methoxy to dimethylamine group. Ground state absorption spectra show a small red shift of about 10 nm and 18 nm while the fluorescence emission spectra show a large red shift of about 66 nm and 162 nm on changing from the nonpolar cyclohexane to the aprotic polar DMSO for MOT and DMAT, respectively. Dipole moment change from the ground state to the charge transfer excited state is calculated to be 6.6 D in MOT and 9.0 D in DMAT. The fluorescence quantum yield, fluorescence lifetime and the derived radiative and non-radiative rate constants were found to be better correlated to the emission energy rather than any of the solvent properties. Three multi-parametric relationships were used in the interpretation of the specific versus non-specific solute-solvent interactions, namely, Kamlet-Taft, Catalán and Laurence et al. models. The findings of these approaches are used to extract useful information about different aspects of solvent effects on the photophysical properties of the two studied compounds. Kamlet-Taft solvatochromic model indicates that non-specific interactions are dominant in controlling the photophysical properties. Catalán's solvent dipolarity/polarizability parameter is found to play a significant role in solvatochromic behaviour which is also designated by the Laurence model.
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Affiliation(s)
- Hussain A Z Sabek
- Department of Chemistry, Faculty of Science, Ain Shams University Abbassia 11566 Cairo Egypt +201097998330
| | - Ahmed M M Alazaly
- Department of Chemistry, Faculty of Science, Ain Shams University Abbassia 11566 Cairo Egypt +201097998330
| | - Dina Salah
- Department of Physics, Faculty of Science, Ain Shams University Abbassia 11566 Cairo Egypt
| | - Hesham S Abdel-Samad
- Department of Chemistry, Faculty of Science, Ain Shams University Abbassia 11566 Cairo Egypt +201097998330
| | - Mohamed A Ismail
- Department of Chemistry, Faculty of Science, Mansoura University 35516 Mansoura Egypt
| | - Ayman A Abdel-Shafi
- Department of Chemistry, Faculty of Science, Ain Shams University Abbassia 11566 Cairo Egypt +201097998330
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13
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Janiga E, Kim G, Chmielewski PJ, Lis T, Kim D, Stępień M. Porphyrin-Ryleneimide Hybrids: Low-Bandgap Acceptors in Energy-Transfer Cassettes. Chem Asian J 2020; 15:2854-2858. [PMID: 32667127 DOI: 10.1002/asia.202000762] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Indexed: 11/06/2022]
Abstract
Energy-transfer cassettes consisting of naphthaleneimide-fused metalloporphyrin acceptors (M=Zn and Pd) and BODIPY donors have been designed and synthesized. These systems have rigid pseudo-tetrahedral structures with a donor-acceptor separation of ca. 17.5 Å. Spectroscopic investigations, including femtosecond transient absorption measurements, showed efficient excitation energy transfer (EET) occurring according to the Förster mechanism. Strong fluorescence of the donor units and significant spectral overlap of the donor and acceptor subunits are prerequisites for the efficient EET in these systems.
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Affiliation(s)
- Ewelina Janiga
- Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383, Wrocław, Poland
| | - Gakhyun Kim
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul, 03722, Korea
| | - Piotr J Chmielewski
- Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383, Wrocław, Poland
| | - Tadeusz Lis
- Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383, Wrocław, Poland
| | - Dongho Kim
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul, 03722, Korea
| | - Marcin Stępień
- Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383, Wrocław, Poland
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Sutton JJ, Li Y, Ryu HS, Tay EJ, Woo HY, Gordon KC. Fluorination Position: A Study of the Optoelectronic Properties of Two Regioisomers Using Spectroscopic and Computational Techniques. J Phys Chem A 2020; 124:7685-7691. [DOI: 10.1021/acs.jpca.0c05210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joshua J. Sutton
- Department of Chemistry, University of Otago, Dunedin and MacDiarmid Institute, Dunedin 9016, New Zealand
| | - Yuxiang Li
- Department of Chemistry, College of Science, Korea University, Seoul 02841, Republic of Korea
| | - Hwa Sook Ryu
- Department of Chemistry, College of Science, Korea University, Seoul 02841, Republic of Korea
| | - Elliot J. Tay
- Department of Chemistry, University of Otago, Dunedin and MacDiarmid Institute, Dunedin 9016, New Zealand
| | - Han Young Woo
- Department of Chemistry, College of Science, Korea University, Seoul 02841, Republic of Korea
| | - Keith C. Gordon
- Department of Chemistry, University of Otago, Dunedin and MacDiarmid Institute, Dunedin 9016, New Zealand
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The Dependence of Implicit Solvent Model Parameters and Electronic Absorption Spectra and Photoinduced Charge Transfer. Sci Rep 2020; 10:3713. [PMID: 32111955 PMCID: PMC7048810 DOI: 10.1038/s41598-020-60757-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 02/17/2020] [Indexed: 11/20/2022] Open
Abstract
In this work, the relationship between multiple solvent parameters and charge transfer index was analyzed by multi-factor multi-variate partial least squares regression (PLSR). The charge transfer of the molecule is visualized by the analysis of the excited state wave function. Hydrogen bond basicity and surface tension can significantly affect charge transfer by studying the solvation model parameters and charge transfer index. Finally, a method in which a solvent regulates charge transfer strength and migration length is proposed.
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16
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Patrizi B, Cozza C, Pietropaolo A, Foggi P, Siciliani de Cumis M. Synergistic Approach of Ultrafast Spectroscopy and Molecular Simulations in the Characterization of Intramolecular Charge Transfer in Push-Pull Molecules. Molecules 2020; 25:E430. [PMID: 31968694 PMCID: PMC7024558 DOI: 10.3390/molecules25020430] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/14/2020] [Accepted: 01/17/2020] [Indexed: 11/28/2022] Open
Abstract
The comprehensive characterization of Intramolecular Charge Transfer (ICT) stemming in push-pull molecules with a delocalized π-system of electrons is noteworthy for a bespoke design of organic materials, spanning widespread applications from photovoltaics to nanomedicine imaging devices. Photo-induced ICT is characterized by structural reorganizations, which allows the molecule to adapt to the new electronic density distribution. Herein, we discuss recent photophysical advances combined with recent progresses in the computational chemistry of photoactive molecular ensembles. We focus the discussion on femtosecond Transient Absorption Spectroscopy (TAS) enabling us to follow the transition from a Locally Excited (LE) state to the ICT and to understand how the environment polarity influences radiative and non-radiative decay mechanisms. In many cases, the charge transfer transition is accompanied by structural rearrangements, such as the twisting or molecule planarization. The possibility of an accurate prediction of the charge-transfer occurring in complex molecules and molecular materials represents an enormous advantage in guiding new molecular and materials design. We briefly report on recent advances in ultrafast multidimensional spectroscopy, in particular, Two-Dimensional Electronic Spectroscopy (2DES), in unraveling the ICT nature of push-pull molecular systems. A theoretical description at the atomistic level of photo-induced molecular transitions can predict with reasonable accuracy the properties of photoactive molecules. In this framework, the review includes a discussion on the advances from simulation and modeling, which have provided, over the years, significant information on photoexcitation, emission, charge-transport, and decay pathways. Density Functional Theory (DFT) coupled with the Time-Dependent (TD) framework can describe electronic properties and dynamics for a limited system size. More recently, Machine Learning (ML) or deep learning approaches, as well as free-energy simulations containing excited state potentials, can speed up the calculations with transferable accuracy to more complex molecules with extended system size. A perspective on combining ultrafast spectroscopy with molecular simulations is foreseen for optimizing the design of photoactive compounds with tunable properties.
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Affiliation(s)
- Barbara Patrizi
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy; (B.P.); (P.F.)
- European Laboratory for Non-Linear Spectroscopy (LENS),Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Concetta Cozza
- Dipartimento di Scienze della Salute, Università di Catanzaro, Viale Europa, 88100 Catanzaro, Italy; (C.C.); (A.P.)
| | - Adriana Pietropaolo
- Dipartimento di Scienze della Salute, Università di Catanzaro, Viale Europa, 88100 Catanzaro, Italy; (C.C.); (A.P.)
| | - Paolo Foggi
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy; (B.P.); (P.F.)
- European Laboratory for Non-Linear Spectroscopy (LENS),Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
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17
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Chen Y, Lu R, Wang W, Wang Q, Chi X, Zhang H. Solvent‐dependent ultrafast optical response of conjugated push–pull chromophores. LUMINESCENCE 2020; 35:572-579. [DOI: 10.1002/bio.3758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 11/25/2019] [Accepted: 12/02/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Ying Chen
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of PhysicsJilin University Changchun People's Republic of China
- College of PhysicsChangchun Normal University Changchun People's Republic of China
| | - Ran Lu
- College of ChemistryJilin University Changchun People's Republic of China
| | - WenYan Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of PhysicsJilin University Changchun People's Republic of China
| | - Quan Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of PhysicsJilin University Changchun People's Republic of China
| | - Xiao‐Chun Chi
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of PhysicsJilin University Changchun People's Republic of China
| | - Han‐Zhuang Zhang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of PhysicsJilin University Changchun People's Republic of China
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18
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Niu X, Kuang Z, Planells M, Guo Y, Robertson N, Xia A. Electron-donating strength dependent symmetry breaking charge transfer dynamics of quadrupolar molecules. Phys Chem Chem Phys 2020; 22:15743-15750. [DOI: 10.1039/d0cp02527e] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solvent induced excited state symmetry breaking processes of donor–acceptor–donor quadrupolar dyes are successfully tracked in real-time.
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Affiliation(s)
- Xinmiao Niu
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key laboratory of Photochemistry
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
| | - Zhuoran Kuang
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key laboratory of Photochemistry
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
| | - Miquel Planells
- EastChem – School of Chemistry
- University of Edinburgh
- Edinburgh EH9 3JJ
- UK
| | - Yuanyuan Guo
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key laboratory of Photochemistry
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
| | - Neil Robertson
- EastChem – School of Chemistry
- University of Edinburgh
- Edinburgh EH9 3JJ
- UK
| | - Andong Xia
- Beijing National Laboratory for Molecular Sciences (BNLMS)
- Key laboratory of Photochemistry
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
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19
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Siddiqui QT, Awasthi AA, Bhui P, Parab P, Muneer M, Bose S, Agarwal N. TADF and exciplex emission in a xanthone-carbazole derivative and tuning of its electroluminescence with applied voltage. RSC Adv 2019; 9:40248-40254. [PMID: 35542672 PMCID: PMC9076223 DOI: 10.1039/c9ra08227a] [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: 10/09/2019] [Accepted: 11/26/2019] [Indexed: 11/21/2022] Open
Abstract
Materials showing white light emission have found applications in a variety of solid state devices especially in display technology. For white light emission, doping of red (R), green (G) and blue (B) emitters in a host matrix is commonly practised. However, finding RGB emitters of similar stability with homogenous doping is challenging. Furthermore, such devices suffer from color purity in the long run. Small organic light emitters, capable of colour tuning and having a broad emission spectrum are in high demand as they provide colour stability, reproducibility, a simple device geometry and high efficiency. Recently, it has been shown that the efficiency of OLEDs can be enhanced by employing thermally activated delayed fluorescence (TADF) materials. Here, we designed and synthesised a xanthone-carbazole based D-A-D material (Xan-Cbz) for TADF properties. Blue TADF emission, in neat thin films, at 470 nm was observed and further investigated by studying delayed fluorescence and lifetime measurements. In addition, a blend of Xan-Cbz with NPD shows exciplex emission at 525 nm in thin film. OLEDs based on Xan-Cbz were fabricated using several device configurations. OLEDs having the device configuration ITO/PEDOT:PSS/NPD/Xan-Cbz/Bphen/LiF-Al showed a luminance of 1.96 × 104 Cd m-2 (at a current density of 50 mA cm-2) and V ON at ∼6 V. Electroluminescence showed the features of both neat emission (470 nm) of Xan-Cbz and its exciplex (525 nm) with NPD. Further, colour tuning was observed as a function of applied voltage and the ratio of light intensity (I 525/I 470) of neat and exciplex emission was found to decrease with increasing voltage. Greenish-blue emission (CIE coordinates: 0.202, 0.382) from Xan-Cbz OLEDs was obtained. Xan-Cbz showed its neat emission (at 470 nm) in ITO/PEDOT:PSS/CBP/Xan-Cbz/Bphen/LiF-Al and pure exciplex emission (at 525 nm) in ITO/PEDOT:PSS/NPD:Xan-Cbz/Bphen/LiF-Al device configurations. Thus in this article we showed blue TADF emission, exciplex emission and voltage dependent color tuning in OLEDs based on a small organic emitter.
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Affiliation(s)
- Qamar T Siddiqui
- School of Chemical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
- Department of Chemistry, Aligarh Muslim University Aligarh India
| | - Ankur A Awasthi
- School of Chemical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
| | - Prabhjyot Bhui
- School of Physical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
| | - Pradnya Parab
- School of Physical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
| | - Mohammad Muneer
- Department of Chemistry, Aligarh Muslim University Aligarh India
| | - Sangita Bose
- School of Physical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
| | - Neeraj Agarwal
- School of Chemical Sciences, UM-DAE, Centre for Excellence in Basic Sciences, University of Mumbai Santacruz (E) Mumbai 400098 India
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21
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Wang K, Gao Z, Zhang W, Yan Y, Song H, Lin X, Zhou Z, Meng H, Xia A, Yao J, Zhao YS. Exciton funneling in light-harvesting organic semiconductor microcrystals for wavelength-tunable lasers. SCIENCE ADVANCES 2019; 5:eaaw2953. [PMID: 31214651 PMCID: PMC6570508 DOI: 10.1126/sciadv.aaw2953] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 05/07/2019] [Indexed: 05/12/2023]
Abstract
Organic solid-state lasers are essential for various photonic applications, yet current-driven lasing remains a great challenge. Charge transfer (CT) complexes formed with p-/n-type organic semiconductors show great potential in electrically pumped lasers, but it is still difficult to achieve population inversion owing to substantial nonradiative loss from delocalized CT states. Here, we demonstrate the lasing action of CT complexes based on exciton funneling in p-type organic microcrystals with n-type doping. The CT complexes with narrow bandgap were locally formed and surrounded by the hosts with high-lying energy levels, which behave as artificial light-harvesting systems. Excitation light energy captured by the hosts was delivered to the CT complexes, functioning as exciton funnels to benefit lasing actions. The lasing wavelength of such composite microcrystals was further modulated by varying the degree of CT. The results offer a comprehensive understanding of exciton funneling in light-harvesting systems for the development of high-performance organic lasing devices.
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Affiliation(s)
- Kang Wang
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenhua Gao
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Zhang
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Yongli Yan
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- Corresponding author. (Y.Y.); (Y.S.Z.)
| | - Hongwei Song
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xianqing Lin
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhonghao Zhou
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haibing Meng
- University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Andong Xia
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiannian Yao
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong Sheng Zhao
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Corresponding author. (Y.Y.); (Y.S.Z.)
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