1
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Shahu A, Petropoulos V, Saridakis E, Petrakis VS, Ioannidis N, Mitrikas G, Schiza A, Chochos CL, Kasimati EM, Soultati A, Nika MC, Thomaidis NS, Fakis M, Maiuri M, Cerullo G, Pistolis G. Aggregation-Driven Photoinduced α-C(sp 3)-H Bond Hydroxylation/C(sp 3)-C(sp 3) Coupling of Boron Dipyrromethene Dye in Water Reported by Near-Infrared Emission. J Am Chem Soc 2024; 146:15659-15665. [PMID: 38819953 PMCID: PMC11190975 DOI: 10.1021/jacs.4c02019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/23/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Molecular aggregation is a powerful tool for tuning advanced materials' photophysical and electronic properties. Here we present a novel potential for the aqueous-solvated aggregated state of boron dipyrromethene (BODIPY) to facilitate phototransformations otherwise achievable only under harsh chemical conditions. We show that the photoinduced symmetry-breaking charge separation state can itself initiate catalyst-free redox chemistry, leading to selective α-C(sp3)-H bond activation/Csp3-Csp3 coupling on the BODIPY backbone. The photoproduction progress was tracked by monitoring the evolution of the strong Stokes-shifted near-infrared emission, resulting from selective self-assembly of the terminal heterodimeric photoproduct into well-ordered J-aggregates, as revealed by X-ray structural analysis. These findings provide a facile and green route to further explore the promising frontier of packing-triggered selective photoconversions via supramolecular engineering.
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Affiliation(s)
- Adelajda Shahu
- Department
of Chemistry, National and Kapodistrian
University of Athens, Athens 15771, Greece
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - Vasilis Petropoulos
- Department
of Physics, University of Patras, Patras 26504, Greece
- Department
of Physics, Politecnico di Milano, Milano 20133, Italy
| | - Emmanuel Saridakis
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - Vyron S. Petrakis
- Department
of Chemistry, National and Kapodistrian
University of Athens, Athens 15771, Greece
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - Nikolaos Ioannidis
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - George Mitrikas
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - Andriana Schiza
- Department
of Chemistry, National and Kapodistrian
University of Athens, Athens 15771, Greece
- Institute
of Chemical Biology, National Hellenic Research
Foundation, Athens 11635, Greece
| | - Christos L. Chochos
- Institute
of Chemical Biology, National Hellenic Research
Foundation, Athens 11635, Greece
| | | | - Anastasia Soultati
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
| | - Maria Christina Nika
- Department
of Chemistry, National and Kapodistrian
University of Athens, Athens 15771, Greece
| | - Nikolaos S. Thomaidis
- Department
of Chemistry, National and Kapodistrian
University of Athens, Athens 15771, Greece
| | - Mihalis Fakis
- Department
of Physics, University of Patras, Patras 26504, Greece
| | | | - Giulio Cerullo
- Department
of Physics, Politecnico di Milano, Milano 20133, Italy
| | - George Pistolis
- Institute
of Nanoscience & Nanotechnology, NCSR
“Demokritos”, Athens 15310, Greece
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2
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Gorman J, Hart SM, John T, Castellanos MA, Harris D, Parsons MF, Banal JL, Willard AP, Schlau-Cohen GS, Bathe M. Sculpting photoproducts with DNA origami. Chem 2024; 10:1553-1575. [PMID: 38827435 PMCID: PMC11138899 DOI: 10.1016/j.chempr.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Natural light-harvesting systems spatially organize densely packed dyes in different configurations to either transport excitons or convert them into charge photoproducts, with high efficiency. In contrast, artificial photosystems like organic solar cells and light-emitting diodes lack this fine structural control, limiting their efficiency. Thus, biomimetic multi-dye systems are needed to organize dyes with the sub-nanometer spatial control required to sculpt resulting photoproducts. Here, we synthesize 11 distinct perylene diimide (PDI) dimers integrated into DNA origami nanostructures and identify dimer architectures that offer discrete control over exciton transport versus charge separation. The large structural-space and site-tunability of origami uniquely provides controlled PDI dimer packing to form distinct excimer photoproducts, which are sensitive to interdye configurations. In the future, this platform enables large-scale programmed assembly of dyes mimicking natural systems to sculpt distinct photophysical products needed for a broad range of optoelectronic devices, including solar energy converters and quantum information processors.
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Affiliation(s)
- Jeffrey Gorman
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- These authors contributed equally
| | - Stephanie M. Hart
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- These authors contributed equally
| | - Torsten John
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Maria A. Castellanos
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Dvir Harris
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Molly F. Parsons
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - James L. Banal
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Adam P. Willard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | - Mark Bathe
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Lead contact
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3
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Kang S, Choi W, Ahn J, Kim T, Oh JH, Kim D. Impact of Packing Geometry on Excimer Characteristics and Mobility in Perylene Bisimide Polycrystalline Films. ACS APPLIED MATERIALS & INTERFACES 2024; 16:18134-18143. [PMID: 38554079 DOI: 10.1021/acsami.3c19140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/01/2024]
Abstract
Efficient exciton transport is essential for high-performance optoelectronics. Considerable efforts have been focused on improving the exciton mobility in organic materials. While it is feasible to improve mobility in organic systems by forming well-ordered stacks, the formation of trap states, particularly the lower-lying states referred to as excimers, remains a significant challenge to enhancing mobility. The mobility of excimer excitons intricately depends on the strength of excitonic coupling in terms of Förster-type diffusive exciton transfer processes. Given that the formation and mobility of excimer excitons are highly sensitive to molecular arrangements (packing geometries), conducting comprehensive investigations into the structure-property relationship in organic systems is crucial. In this study, we prepared three types of polycrystalline films of perylene bisimide (PBI) by varying substituents at the imide and bay positions, which allowed us to tailor the properties of excimer excitons and their mobility based on packing geometries and excitonic coupling strengths. By utilizing femtosecond transient absorption spectroscopy, we observed ultrafast excimer formation in the higher coupling regime, while in the lower coupling regime, the transition from Frenkel to excimer excitons occurs with a time constant of 500 fs. Under high pump-fluence, exciton-exciton annihilation processes occur, indicating the diffusion of excimer excitons. Intriguingly, employing a three-dimensional diffusion model, we derived a diffusion constant that is 3000 times greater in the high coupling regime than in the low coupling regime. To investigate the optoelectronic properties in the form of a bulk system, we fabricated n-type organic field effect transistors and obtained 8000 times higher mobility in the high coupling regime. Furthermore, photocurrent measurements enable us to investigate the charge carrier transport by mobile excimer excitons, suggesting a 230-fold improvement in external quantum efficiency with tightly packing PBI molecules compared to the low coupling regime. These findings not only offer valuable insights into optimizing organic materials for optoelectronic devices but also unveil the intriguing potential of exciton migration within excimers.
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Affiliation(s)
- Seongsoo Kang
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Wonbin Choi
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Jaeyong Ahn
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Taeyeon Kim
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Joon Hak Oh
- School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
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4
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Yahagh A, Kaswan RR, Kazemi S, Karr PA, D'Souza F. Symmetry breaking charge transfer leading to charge separation in a far-red absorbing bisstyryl-BODIPY dimer. Chem Sci 2024; 15:906-913. [PMID: 38239676 PMCID: PMC10793208 DOI: 10.1039/d3sc05034c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 12/14/2023] [Indexed: 01/22/2024] Open
Abstract
Symmetry breaking charge transfer is one of the important photo-events occurring in photosynthetic reaction centers that is responsible for initiating electron transfer leading to a long-lived charge-separated state and has been successfully employed in light-to-electricity converting optoelectronic devices. In the present study, we report a newly synthesized, far-red absorbing and emitting BODIPY-dimer to undergo symmetry-breaking charge transfer leading to charge-separated states of appreciable lifetimes in polar solvents. Compared to its monomer analog, both steady-state and time-resolved fluorescence originating from the S1 state of the dimer revealed quenching which increased with an increase in solvent polarity. The electrostatic potential map from DFT and the time-dependent DFT calculations suggested the existence of a quadrupolar type charge transfer state in polar solvents, and the singlet excited state to be involved in the charge separation process. The electrochemically determined redox gap being smaller than the energy of the S1 state supported the thermodynamic feasibility of the envisioned symmetry-breaking charge transfer and separation. The spectrum of the charge-separated state arrived from spectroelectrochemical studies, revealing diagnostic peaks helpful for transient spectral interpretation. Finally, ultrafast transient pump-probe spectroscopy provided conclusive evidence of diabatic charge separation in polar solvents by far-red pulsed laser light irradiation. The measured lifetime of the final charge-separated states was found to be 165 ps in dichlorobenzene, 140 ps in benzonitrile, and 43 ps in dimethyl sulfoxide, revealing their significance in light energy harvesting, especially from the less-explored far-red region.
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Affiliation(s)
- Aida Yahagh
- Department of Chemistry, University of North Texas 1155 Union Circle #305070 Denton TX 76203-5017 USA
| | - Ram R Kaswan
- Department of Chemistry, University of North Texas 1155 Union Circle #305070 Denton TX 76203-5017 USA
| | - Shahrzad Kazemi
- Department of Chemistry, University of North Texas 1155 Union Circle #305070 Denton TX 76203-5017 USA
| | - Paul A Karr
- Department of Physical Sciences and Mathematics, Wayne State College 111 Main Street Wayne NE 68787 USA
| | - Francis D'Souza
- Department of Chemistry, University of North Texas 1155 Union Circle #305070 Denton TX 76203-5017 USA
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5
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Orihashi K, Yamauchi A, Inoue M, Parmar B, Fujiwara S, Kimizuka N, Asada M, Nakamura T, Yanai N. Radical qubits photo-generated in acene-based metal-organic frameworks. Dalton Trans 2024; 53:872-876. [PMID: 38164969 DOI: 10.1039/d3dt03959e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
A series of metal-organic frameworks (MOFs) assembled with diazatetracene (DAT)-based linkers were synthesized and characterized. Despite different chromophore orientations and spacings, photoinduced persistent radicals were generated in all the MOFs, and their spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) were found to be relatively long even at room temperature. The generality of long T1 and T2 values of photogenerated radicals in the chromophore-assembled MOFs provides a new platform towards quantum sensing applications.
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Affiliation(s)
- Kana Orihashi
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Akio Yamauchi
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Miku Inoue
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Bhavesh Parmar
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Saiya Fujiwara
- RIKEN Center for Emergent Matter Science, Riken, Wako, Saitama 351-0198, Japan
| | - Nobuo Kimizuka
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | - Mizue Asada
- Institute for Molecular Science, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan
| | - Toshikazu Nakamura
- Institute for Molecular Science, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan
| | - Nobuhiro Yanai
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
- FOREST, CREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
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6
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Lin C, O'Connor JP, Phelan BT, Young RM, Wasielewski MR. Ultrafast Charge Transfer Dynamics in a Slip-Stacked Donor-Acceptor-Acceptor System. J Phys Chem A 2024; 128:244-250. [PMID: 38153126 DOI: 10.1021/acs.jpca.3c07539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Photoexcitation of molecular electron donor and/or acceptor chromophore aggregates can greatly affect their charge-transfer dynamics. Excitonic coupling not only alters the energy landscape in the excited state but may also open new photophysical pathways, such as symmetry-breaking charge separation (SB-CS). Here, we investigate the impact of excitonic coupling on a covalent donor-acceptor-acceptor system comprising a perylene donor (Per) and two perylenediimide (PDI) acceptor chromophores in which the three components are π-stacked in a geometry that is slipped along their long axes (Per-PDI2). Following selective photoexcitation of PDI, femtosecond transient absorption data for Per-PDI2 is compared to that for the single-donor, single-acceptor Per-PDI system, and the PDI2 dimer, which both have the same interchromophore geometry as Per-PDI2. The data show that electron transfer from Per to the lower exciton state of the PDI dimer is slower than that of the single PDI acceptor system. This is due to the lower free energy of the reaction for charge separation because of the electronic stabilization afforded by the excitonic coupling between the PDIs. While PDI2 was shown previously to undergo ultrafast SB-CS, the strong π-π electronic interaction of Per with the adjacent PDI in Per-PDI2 breaks the electronic symmetry of the PDI dimer, resulting in the oxidation of Per rather than SB-CS. These results show that the electronic coupling between molecules designed to accept charges produced by SB-CS in molecular dimers and the chromophores comprising the dimer must be balanced to favor SB-CS.
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Affiliation(s)
- Chenjian Lin
- Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - James P O'Connor
- Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Brian T Phelan
- Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M Young
- Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
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7
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Orihashi K, Yamauchi A, Fujiwara S, Asada M, Nakamura T, Ka-Ho Hui J, Kimizuka N, Tateishi K, Uesaka T, Yanai N. Spin-Polarized Radicals with Extremely Long Spin-Lattice Relaxation Time at Room Temperature in a Metal-Organic Framework. J Am Chem Soc 2023; 145:27650-27656. [PMID: 38079364 DOI: 10.1021/jacs.3c09563] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The generation of spin polarization is key in quantum information science and dynamic nuclear polarization. Polarized electron spins with long spin-lattice relaxation times (T1) at room temperature are important for these applications but have been difficult to achieve. We report the realization of spin-polarized radicals with extremely long T1 at room temperature in a metal-organic framework (MOF) in which azaacene chromophores are densely integrated. Persistent radicals are generated in the MOF by charge separation after photoexcitation. Spin polarization of a triplet generated by photoexcitation is successfully transferred to the persistent radicals. Pulse electron spin resonance measurements reveal that the T1 of the polarized radical in the MOF is as long as 214 μs with a relatively long spin-spin relaxation time T2 of the radicals of up to 0.98 μs at room temperature. The achievement of extremely long spin polarization in MOFs with nanopores accessible to guest molecules will be an important cornerstone for future highly sensitive quantum sensing and efficient dynamic nuclear polarization.
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Affiliation(s)
- Kana Orihashi
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Akio Yamauchi
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Saiya Fujiwara
- RIKEN Center for Emergent Matter Science, Riken, Wako, Saitama 351-0198, Japan
| | - Mizue Asada
- Institute for Molecular Science, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan
| | - Toshikazu Nakamura
- Institute for Molecular Science, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Japan
| | - Joseph Ka-Ho Hui
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Nobuo Kimizuka
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kenichiro Tateishi
- Cluster for Pioneering Research, Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tomohiro Uesaka
- Cluster for Pioneering Research, Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Nobuhiro Yanai
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- FOREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
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8
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Bradley JM, Coleman AF, Brown PJ, Huang Y, Young RM, Wasielewski MR. Harvesting electrons and holes from photodriven symmetry-breaking charge separation within a perylenediimide photosynthetic model dimer. Proc Natl Acad Sci U S A 2023; 120:e2313575120. [PMID: 37983509 PMCID: PMC10691211 DOI: 10.1073/pnas.2313575120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 10/11/2023] [Indexed: 11/22/2023] Open
Abstract
Understanding how to utilize symmetry-breaking charge separation (SB-CS) offers a path toward increasingly efficient light-harvesting technologies. This process plays a central role in the first step of photosynthesis, in which the dimeric "special pair" of the photosynthetic reaction center enters a coherent SB-CS state after photoexcitation. Previous research on SB-CS in both biological and synthetic chromophore dimers has focused on increasing the efficiency of light-driven processes. In a chromophore dimer undergoing SB-CS, the energy of the radical ion pair product is nearly isoenergetic with that of the lowest excited singlet (S1) state of the dimer. This means that very little energy is lost from the absorbed photon. In principle, the relatively high energy electron and hole generated by SB-CS within the chromophore dimer can each be transferred to adjacent charge acceptors to extend the lifetime of the electron-hole pair, which can increase the efficiency of solar energy conversion. To investigate this possibility, we have designed a bis-perylenediimide cyclophane (mPDI2) covalently linked to a secondary electron donor, peri-xanthenoxanthene (PXX) and a secondary electron acceptor, partially fluorinated naphthalenediimide (FNDI). Upon selective photoexcitation of mPDI2, transient absorption spectroscopy shows that mPDI2 undergoes SB-CS, followed by two secondary charge transfer reactions to generate a PXX•+-mPDI2-FNDI•- radical ion pair having a nearly 3 µs lifetime. This strategy has the potential to increase the efficiency of molecular systems for artificial photosynthesis and photovoltaics.
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Affiliation(s)
- Jillian M. Bradley
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
| | - Adam F. Coleman
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
| | - Paige J. Brown
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
| | - Yuheng Huang
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
| | - Ryan M. Young
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
| | - Michael R. Wasielewski
- Department of Chemistry, Northwestern University, Evanston, IL60208-3113
- Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, IL60208-3113
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9
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Zaima T, Ota W, Haruta N, Uejima M, Ohkita H, Sato T. Spontaneous-Symmetry-Breaking Charge Separation Induced by Pseudo-Jahn-Teller Distortion in Organic Photovoltaic Material. J Phys Chem Lett 2023; 14:9706-9712. [PMID: 37877625 DOI: 10.1021/acs.jpclett.3c02527] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
The driving force of charge separation in the initial photovoltaic conversion process is theoretically investigated using ITIC, a nonfullerene acceptor material for organic photovoltaic devices. The density functional theory calculations show that the pseudo-Jahn-Teller (PJT) distortion of the S1 excimer state induces spontaneous symmetry-breaking charge separation between the identical ITIC molecules even without the asymmetry of the surrounding environment. The strong PJT effect arises from the vibronic coupling between the pseudodegenerate S1 and S2 excited states with different irreducible representations (irreps), i.e., Au for S1 and Ag for S2, via the asymmetric vibrational mode with the Au irrep. The vibrational mode responsible for the spontaneous polarization, which is opposite in one ITIC monomer and the other, is the intramolecular C-C stretching vibration between the core IT and terminal IC units. These results suggest that controlling the PJT effect can improve the charge separation efficiency of the initial photovoltaic conversion process.
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Affiliation(s)
- Takeaki Zaima
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Wataru Ota
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Naoki Haruta
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Motoyuki Uejima
- MOLFEX, Inc., Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, Japan
| | - Hideo Ohkita
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Tohru Sato
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishibiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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10
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Zhao X, He S, Wang J, Ding J, Zong S, Li G, Sun W, Du J, Fan J, Peng X. Near-Infrared Self-Assembled Hydroxyl Radical Generator Based on Photoinduced Cascade Electron Transfer for Hypoxic Tumor Phototherapy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2305163. [PMID: 37545041 DOI: 10.1002/adma.202305163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/22/2023] [Indexed: 08/08/2023]
Abstract
The hydroxyl radical (•OH) is an extremely potent reactive oxygen species that plays a crucial role in photooxidations within the realm of hypoxic tumor therapy. However, the current methods for •OH photogeneration typically rely on inorganic materials that require UV/vis light excitation. Consequently, photogenerators based on organic molecules, especially those utilizing near-infrared (NIR) light excitation, are rare. In this study, the concept of photoinduced cascade charge transfer (PICET), which utilizes NIR heavy-atom-free photosensitizers (ANOR-Cy5) to generate •OH is introduced. The ANOR-Cy5 photosensitizer, with its flexible hydrophobic structure, enables the formation of nanoparticles in aqueous solutions through molecular assembly. PICET involves a symmetry-breaking charge separation-induced localized charge-separated state, transitioning to a delocalized charge-separated state, which governs the efficiency of •OH generation. Thanks to the oxygen-independent nature of •OH generation and its robust oxidative properties, the ANOR-Cy5-based photosensitizer demonstrates highly effective photoinduced anti-cancer effects, even under severely hypoxic conditions. This discovery emphasizes the potential for achieving •OH photogeneration using a single organic molecule through the engineering of molecular self-assembly, thereby opening up new possibilities for phototherapy and beyond.
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Affiliation(s)
- Xueze Zhao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - Shan He
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Junfeng Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Junying Ding
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
| | - Shenglin Zong
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
| | - Guohui Li
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Wen Sun
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
| | - Jianjun Du
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
| | - Jiangli Fan
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
| | - Xiaojun Peng
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China
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11
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Zhang M, Johnson CE, Ilic A, Schwarz J, Johansson MB, Lomoth R. High-Efficiency Photoinduced Charge Separation in Fe(III)carbene Thin Films. J Am Chem Soc 2023; 145:19171-19176. [PMID: 37616472 PMCID: PMC10485928 DOI: 10.1021/jacs.3c05404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Indexed: 08/26/2023]
Abstract
Symmetry-breaking charge separation in molecular materials has attracted increasing attention for optoelectronics based on single-material active layers. To this end, Fe(III) complexes with particularly electron-donating N-heterocyclic carbene ligands offer interesting properties with a 2LMCT excited state capable of oxidizing or reducing the complex in its ground state. In this Communication, we show that the corresponding symmetry-breaking charge separation occurs in amorphous films of pristine [Fe(III)L2]PF6 (L = [phenyl(tris(3-methylimidazol-2-ylidene))borate]-). Excitation of the solid material with visible light leads to ultrafast electron transfer quenching of the 2LMCT excited state, generating Fe(II) and Fe(IV) products with high efficiency. Sub-picosecond charge separation followed by recombination in about 1 ns could be monitored by transient absorption spectroscopy. Photoconductivity measurements of films deposited on microelectrode arrays demonstrated that photogenerated charge carriers can be collected at external contacts.
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Affiliation(s)
- Minli Zhang
- Department
of Chemistry - Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
| | - Catherine E. Johnson
- Department
of Chemistry - Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
| | - Aleksandra Ilic
- Center
for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, SE-22100 Lund, Sweden
| | - Jesper Schwarz
- Center
for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, SE-22100 Lund, Sweden
| | - Malin B. Johansson
- Department
of Chemistry - Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
| | - Reiner Lomoth
- Department
of Chemistry - Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
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12
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Rehhagen C, Rather SR, Schwarz KN, Scholes GD, Lochbrunner S. Comparison of Frenkel and Excimer Exciton Diffusion in Perylene Bisimide Nanoparticles. J Phys Chem Lett 2023; 14:4490-4496. [PMID: 37155571 DOI: 10.1021/acs.jpclett.3c00364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Exciton migration is an important process for light harvesting with organic systems and often the bottleneck. Especially the formation of trap states hinders the mobility considerably. Although excimer excitons are often referred to as traps, their mobility has been demonstrated while their nature is still unclear. Here, we compare the mobility of singlet and excimer excitons in nanoparticles consisting of the same type of perylene bisimide molecules. By changing the preparation conditions, nanoparticles with different intermolecular coupling strengths are prepared. Femtosecond transient absorption spectroscopy reveals the formation of excimer excitons from Frenkel excitons. The mobility of both exciton types is determined by evaluating exciton-exciton annihilation processes. In the lower coupling regime, singlet mobility is observed, whereas for stronger coupling the dynamics is dominated by a 10-fold increased excimer mobility. The excimer mobility can thus even be higher than the singlet mobility and is affected by the intermolecular electronic coupling.
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Affiliation(s)
- Chris Rehhagen
- Institute for Physics and Department Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
| | - Shahnawaz R. Rather
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Kyra N Schwarz
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Gregory D Scholes
- Frick Laboratory, Princeton University, Princeton, New Jersey 08540, United States
| | - Stefan Lochbrunner
- Institute for Physics and Department Life, Light and Matter, University of Rostock, 18051 Rostock, Germany
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13
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Sebastian E, Hariharan M. A Symmetry-Broken Charge-Separated State in the Marcus Inverted Region. Angew Chem Int Ed Engl 2023; 62:e202216482. [PMID: 36697363 DOI: 10.1002/anie.202216482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/23/2022] [Accepted: 01/24/2023] [Indexed: 01/27/2023]
Abstract
We report a long-lived charge-separated state in a chromophoric pair (DC-PDI2 ) that uniquely integrates the advantages of fundamental processes of photosynthetic reaction centers: i) Symmetry-breaking charge-separation (SB-CS) and ii) Marcus-inverted-region dependence. The near-orthogonal bichromophoric DC-PDI2 manifests an ultrafast evolution of the SB-CS state with a time constant of τ S B - C S ${{\tau }_{{\rm S}{\rm B}-{\rm C}{\rm S}}}$ =0.35±0.02 ps and a slow charge recombination (CR) kinetics with τ C R ${{\tau }_{{\rm C}{\rm R}}}$ =4.09±0.01 ns in ACN. The rate constant of CR of DC-PDI2 is 11 686 times slower than SB-CS in ACN, as the CR of the PDI radical ion-pair occurs in the deep inverted region of the Marcus parabola ( - Δ G C R ${{-{\rm \Delta }G}_{{\rm C}{\rm R}}}$ >λ). In contrast, an analogous benzyloxy (BnO)-substituted DC-BPDI2 showcases a ≈10-fold accelerated CR kinetics with τ C R / τ S B - C S ${{\tau }_{{\rm C}{\rm R}}/{\tau }_{{\rm S}{\rm B}-{\rm C}{\rm S}}}$ lowering to ≈1536 in ACN, by virtue of a decreased CR driving force. The present investigation demonstrates a control of molecular engineering to tune the energetics and kinetics of the SB-CS material, which is essential for next-generation optoelectronic devices.
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Affiliation(s)
- Ebin Sebastian
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram, 695551, Kerala, India
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram, 695551, Kerala, India
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14
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Swathi K, Sujith M, Divya PS, P MV, Delledonne A, Phan Huu DKA, Di Maiolo F, Terenziani F, Lapini A, Painelli A, Sissa C, Thomas KG. From symmetry breaking to symmetry swapping: is Kasha's rule violated in multibranched phenyleneethynylenes? Chem Sci 2023; 14:1986-1996. [PMID: 36845926 PMCID: PMC9945429 DOI: 10.1039/d2sc05206g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 01/12/2023] [Indexed: 01/15/2023] Open
Abstract
The phenomenon of excited-state symmetry breaking is often observed in multipolar molecular systems, significantly affecting their photophysical and charge separation behavior. As a result of this phenomenon, the electronic excitation is partially localized in one of the molecular branches. However, the intrinsic structural and electronic factors that regulate excited-state symmetry breaking in multibranched systems have hardly been investigated. Herein, we explore these aspects by adopting a joint experimental and theoretical investigation for a class of phenyleneethynylenes, one of the most widely used molecular building blocks for optoelectronic applications. The large Stokes shifts observed for highly symmetric phenyleneethynylenes are explained by the presence of low-lying dark states, as also established by two-photon absorption measurements and TDDFT calculations. In spite of the presence of low-lying dark states, these systems show an intense fluorescence in striking contrast to Kasha's rule. This intriguing behavior is explained in terms of a novel phenomenon, dubbed "symmetry swapping" that describes the inversion of the energy order of excited states, i.e., the swapping of excited states occurring as a consequence of symmetry breaking. Thus, symmetry swapping explains quite naturally the observation of an intense fluorescence emission in molecular systems whose lowest vertical excited state is a dark state. In short, symmetry swapping is observed in highly symmetric molecules having multiple degenerate or quasi-degenerate excited states that are prone to symmetry breaking.
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Affiliation(s)
- K. Swathi
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di ParmaParco Area delle Scienze 17A43124ParmaItaly,School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM)VithuraThiruvananthapuram695 551India
| | - Meleppatt Sujith
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM) Vithura Thiruvananthapuram 695 551 India
| | - P. S. Divya
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM)VithuraThiruvananthapuram695 551India
| | - Merin Varghese P
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM) Vithura Thiruvananthapuram 695 551 India
| | - Andrea Delledonne
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - D. K. Andrea Phan Huu
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di ParmaParco Area delle Scienze 17A43124ParmaItaly
| | - Francesco Di Maiolo
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - Francesca Terenziani
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - Andrea Lapini
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - Anna Painelli
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - Cristina Sissa
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma Parco Area delle Scienze 17A 43124 Parma Italy
| | - K. George Thomas
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM)VithuraThiruvananthapuram695 551India
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15
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Dnyaneshwar Veer S, Chandrakant Wakchaure V, Asokan K, Dixit R, Goswami T, Saha R, Gonnade R, Ghosh HN, Santhosh Babu S. Oligothiophene-Ring-Strapped Perylene Bisimides: Functionalizable Coaxial Donor-Acceptor Macrocycles. Angew Chem Int Ed Engl 2023; 62:e202212934. [PMID: 36266975 DOI: 10.1002/anie.202212934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 12/14/2022]
Abstract
Aesthetic designs from nature enable new knowledge to be gained and, at the same time, inspire scientific models. In this context, multicomponent macrocycles embody the advantage of precisely positioning the structural units to achieve efficient communication between them. However, the construction of a functionalizable macrocycle for ultrafast charge separation and stabilization has not been attempted. Herein, we report the synthesis, crystal structure, and transient absorption of a new functionalizable macrocycle consisting of an oligothiophene-ring-strapped perylene bisimide. Transient absorption results point to a sequential improvement in charge separation and stabilization from the macrocycle to the corresponding linear dimer and 2D polymer due to the unique design. Our macrocycle design with a supportive spatial arrangement of the donor and acceptor units will inspire the development of more complex synthetic systems with exciting electron-transfer and charge-separation features.
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Affiliation(s)
- Sairam Dnyaneshwar Veer
- Organic Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201 002, India
| | - Vivek Chandrakant Wakchaure
- Organic Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201 002, India
| | - Kiran Asokan
- Organic Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India
| | - Ruchi Dixit
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201 002, India.,Physical and Materials Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India
| | - Tanmay Goswami
- Institute of Nanoscience and Nanotechnology (INST), Sector 81, Mohali, 411008, Punjab, India
| | - Ramchandra Saha
- Institute of Nanoscience and Nanotechnology (INST), Sector 81, Mohali, 411008, Punjab, India
| | - Rajesh Gonnade
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201 002, India.,Physical and Materials Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India
| | - Hirendra N Ghosh
- Institute of Nanoscience and Nanotechnology (INST), Sector 81, Mohali, 411008, Punjab, India.,Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
| | - Sukumaran Santhosh Babu
- Organic Chemistry Division, National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411 008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201 002, India
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16
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Hammer S, Linderl T, Tvingstedt K, Brütting W, Pflaum J. Spectroscopic analysis of vibrational coupling in multi-molecular excited states. MATERIALS HORIZONS 2023; 10:221-234. [PMID: 36367085 DOI: 10.1039/d2mh00829g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Multi-molecular excited states accompanied by intra- and inter-molecular geometric relaxation are commonly encountered in optical and electrooptical studies and applications of organic semiconductors as, for example, excimers or charge transfer states. Understanding the dynamics of these states is crucial to improve organic devices such as light emitting diodes and solar cells. Their full microscopic description, however, demands sophisticated tools such as ab initio quantum chemical calculations which come at the expense of high computational costs and are prone to errors by assumptions as well as iterative algorithmic procedures. Hence, the analysis of spectroscopic data is often conducted at a phenomenological level only. Here, we present a toolkit to analyze temperature dependent luminescence data and gain first insights into the relevant microscopic parameters of the molecular system at hand. By means of a Franck-Condon based approach considering a single effective inter-molecular vibrational mode and different potentials for the ground and excited state we are able to explain the luminescence spectra of such multi-molecular states. We demonstrate that by applying certain reasonable simplifications the luminescence of charge transfer states as well as excimers can be satisfactorily reproduced for temperatures ranging from cryogenics to above room temperature. We present a semi-classical and a quantum-mechanical description of our model and, for both cases, demonstrate its applicability by analyzing the temperature dependent luminescence of the amorphous donor-acceptor heterojunction tetraphenyldibenzoperiflanthene:C60 as well as polycrystalline zinc-phthalocyanine to reproduce the luminescence spectra and extract relevant system parameters such as the excimer binding energy.
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Affiliation(s)
- Sebastian Hammer
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
| | - Theresa Linderl
- Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Kristofer Tvingstedt
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
| | - Wolfgang Brütting
- Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Jens Pflaum
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
- Bavarian Center for Applied Energy Research, 97074 Würzburg, Germany
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17
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Mohamed AL, Khattab TA, Hassabo AG. Color-tunable encapsulated perylene-labeled silica fluorescent hybrid nanoparticles. RESULTS IN CHEMISTRY 2023. [DOI: 10.1016/j.rechem.2023.100769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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18
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Sebastian E, Sunny J, Hariharan M. Excimer evolution hampers symmetry-broken charge-separated states. Chem Sci 2022; 13:10824-10835. [PMID: 36320683 PMCID: PMC9491171 DOI: 10.1039/d2sc04387d] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 08/18/2022] [Indexed: 08/26/2023] Open
Abstract
Achieving long-lived symmetry-broken charge-separated states in chromophoric assemblies is quintessential for enhanced performance of artificial photosynthetic mimics. However, the occurrence of energy trap states hinders exciton and charge transport across photovoltaic devices, diminishing power conversion efficiency. Herein, we demonstrate unprecedented excimer formation in the relaxed excited-state geometry of bichromophoric systems impeding the lifetime of symmetry-broken charge-separated states. Core-annulated perylenediimide dimers (SC-SPDI2 and SC-NPDI2) prefer a near-orthogonal arrangement in the ground state and a π-stacked foldamer structure in the excited state. The prospect of an excimer-like state in the foldameric arrangement of SC-SPDI2 and SC-NPDI2 has been rationalized by fragment-based excited state analysis and temperature-dependent photoluminescence measurements. Effective electronic coupling matrix elements in the Franck-Condon geometry of SC-SPDI2 and SC-NPDI2 facilitate solvation-assisted ultrafast symmetry-breaking charge-separation (SB-CS) in a high dielectric environment, in contrast to unrelaxed excimer formation (Ex*) in a low dielectric environment. Subsequently, the SB-CS state dissociates into an undesired relaxed excimer state (Ex) due to configuration mixing of a Frenkel exciton (FE) and charge-separated state in the foldamer structure, downgrading the efficacy of the charge-separated state. The decay rate constant of the FE to SB-CS (k FE→SB-CS) in polar solvents is 8-17 fold faster than that of direct Ex* formation (k FE→Ex*) in non-polar solvent (k FE→SB-CS≫k FE→Ex*), characterized by femtosecond transient absorption (fsTA) spectroscopy. The present investigation establishes the impact of detrimental excimer formation on the persistence of the SB-CS state in chromophoric dimers and offers the requisite of conformational rigidity as one of the potential design principles for developing advanced molecular photovoltaics.
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Affiliation(s)
- Ebin Sebastian
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
| | - Jeswin Sunny
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
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19
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Feng Y, Das PJ, Young RM, Brown PJ, Hornick JE, Weber JA, Seale JSW, Stern CL, Wasielewski MR, Stoddart JF. Alkoxy-Substituted Quadrupolar Fluorescent Dyes. J Am Chem Soc 2022; 144:16841-16854. [PMID: 36083184 DOI: 10.1021/jacs.2c04906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polar and polarizable π-conjugated organic molecules containing push-pull chromophores have been investigated extensively in the past. Identifying unique backbones and building blocks for fluorescent dyes is a timely exercise. Here, we report the synthesis and characterization of a series of fluorescent dyes containing quadrupolar A-D-A constitutions (where A = acceptor and D = donor), which exhibit fluorescence emission at a variety of different wavelengths. We have investigated the effects of different electron-withdrawing groups, located at both termini of a para-terphenylene backbone, by steady-state UV/vis and fluorescence spectroscopy. Pyridine and substituted pyridinium units are also introduced during the construction of the quadrupolar backbones. Depending on the quadrupolarity, fluorescence emission wavelengths cover from 380 to 557 nm. Time-resolved absorption and emission spectroscopy reveal that the photophysical properties of those quadrupolar dyes result from intramolecular charge transfer. One of the dyes we have investigated is a symmetrical box-like tetracationic cyclophane. Its water-soluble tetrachloride, which is non-cytotoxic to cells up to a loading concentration of 1 μM, has been employed in live-cell imaging. When taken up by cells, the tetrachloride emits a green fluorescence emission without any hint of photobleaching or disruption of normal cell behavior. We envision that our design strategy of modifying molecules through the functionalization of the quadrupolar building blocks as chromophores will lead to future generations of fluorescent dyes in which these A-D-A constitutional fragments are incorporated into more complex molecules and polymers for broader photophysical and biological applications.
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Affiliation(s)
- Yuanning Feng
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Partha Jyoti Das
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Ryan M Young
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208, United States
| | - Paige J Brown
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208, United States
| | - Jessica E Hornick
- Chemistry for Life Processes Institutes, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,Department of Molecular Biosciences, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Jacob A Weber
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - James S W Seale
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Charlotte L Stern
- Integrated Molecular Structure Education and Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Michael R Wasielewski
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208, United States
| | - J Fraser Stoddart
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,School of Chemistry, University of New South Wales, Sydney 2052, New South Wales, Australia.,Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.,ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China
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20
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Liang H, Tang L, He J, Li J, Chen Z, Cai S, Pang J, Mahmood Z, Chen W, Li MD, Zhao Z, Huo Y, Ji S. Modulating the intersystem crossing mechanism of anthracene carboxyimide-based photosensitizers via structural adjustments and application as a potent photodynamic therapeutic reagent. Phys Chem Chem Phys 2022; 24:20901-20912. [PMID: 36047252 DOI: 10.1039/d2cp02897b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, a series of compact anthracene carboxyimide (ACI) based donor-acceptor dyads were prepared by substituting bulky aryl moieties with various electron-donating ability to study the triplet-excited state properties. The ISC mechanism and triplet yield of the dyads were successfully tuned via structural manipulation. Efficient ISC (ΦΔ ≈ 99%) and long-lived triplet state (τT ≈ 122 μs) was observed for the orthogonal anthracene-labeled ACI derivative compared to the Ph-ACI and NP-ACI dyads, which showed fast triplet state decay (τT ≈ 7.7 μs). Femtosecond transient absorption study demonstrated the ultrafast charge separation (CS) and efficient charge recombination (CR) in the orthogonal dyads and ISC occurring via spin-orbit charge transfer (SOCT) mechanism (AN-ACI: τCS = 355 fs, τCR = 2.41 ns; PY-ACI: τCS = 321 fs, τCR = 1.61 ns), while in Ph-ACI and NP-ACI dyads triplet populate following the normal ISC channel (nπ* → ππ* transition), no CS was observed. We found that the attachment of suitable aryl donor moiety (AN- or PY-) to the ACI core can ensure the insertion of the intermediate triplet state, resulting in a small energy gap among charge separated state (CSS) and triplet state, which leads to efficient ISC in these derivatives. The SOCT-ISC-based AN-ACI dyad was confirmed to be a potent photodynamic therapeutic reagent; an ultra-low IC50 value (0.27 nM) that was nearly 214 times lower than that of the commercial Rose Bengal photosensitizer (57.8 nM) was observed.
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Affiliation(s)
- Hui Liang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Liting Tang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Jiaxing He
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, 515063, P. R. China.
| | - Jianqing Li
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou 510640, P. R. China.
| | - Zeduan Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Shuqing Cai
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Junhong Pang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, 515063, P. R. China.
| | - Zafar Mahmood
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Wencheng Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Ming-De Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou, 515063, P. R. China.
| | - Zujin Zhao
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou 510640, P. R. China.
| | - Yanping Huo
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
| | - Shaomin Ji
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
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21
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Niu X, Tajima K, Kong J, Tao M, Fukui N, Kuang Z, Shinokubo H, Xia A. Symmetry-breaking charge separation in a nitrogen-bridged naphthalene monoimide dimer. Phys Chem Chem Phys 2022; 24:14007-14015. [PMID: 35635531 DOI: 10.1039/d2cp00295g] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photophysical properties of 4-aminonaphthalene-1,8-imide-based derivatives, bis-ANI, consisting of two naphthalimide (NI) units linked by a butylamine bridge and its monomer ANI have been intensively investigated by steady-state and transient spectroscopy combined with quantum chemical calculations. The excited state relaxation dynamics of the two molecules are studied in three solvents of varying polarity - from hexane to tetrahydrofuran to acetone. A strong reduction in the fluorescence quantum yields and larger red shifts of the emission spectra are observed when going from the monomer ANI to dimer bis-ANI with increasing solvent polarity. It is found that the presence of the central amino linker in bis-ANI facilitates the formation of an asymmetric CS state between the ANI and NI moieties in bis-ANI, where NI˙- is the dominant radical anion unit after CS, evidenced by the femtosecond transient absorption measurements and spectroelectrochemistry in polar solvents. Femtosecond transient absorption spectra and quantum chemical calculations reveal the conformational change after the formation of the symmetry-breaking charge separation (SBCS) state upon photoexcitation, while a near-orthogonal structure in the excited state of bis-ANI retards charge recombination. In addition, it is evidenced that the rate of SBCS can be tuned by changing the different polar solvents.
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Affiliation(s)
- Xinmiao Niu
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100176, P. R. China. .,Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Keita Tajima
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Jie Kong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Min Tao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Zhuoran Kuang
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100176, P. R. China.
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Andong Xia
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100176, P. R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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22
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Wang K, Shao G, Peng S, You X, Chen X, Xu J, Huang H, Wang H, Wu D, Xia J. Achieving Symmetry-Breaking Charge Separation in Perylenediimide Trimers: The Effect of Bridge Resonance. J Phys Chem B 2022; 126:3758-3767. [PMID: 35559687 DOI: 10.1021/acs.jpcb.2c02387] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Symmetry-breaking charge separation (SB-CS) provides a very promising option to engineer a novel light conversion scheme, while it is still a challenge to realize SB-CS in a nonpolar environment. The strength of electronic coupling plays a crucial role in determining the exciton dynamics of organic semiconductors. Herein, we describe how to mediate interchromophore coupling to achieve SB-CS in a nonpolar solvent by the use of two perylenediimide (PDI)-based trimers, 1,7-tri-PDI and 1,6-tri-PDI. Although functionalization at the N-atom decreases electronic coupling between PDI units, our strategy takes advantage of "bridge resonance", in which the frontier orbital energies are nearly degenerate with those of the covalently linked PDI units, leading to enhanced interchromophore electronic coupling. Tunable electronic coupling was realized by the judicious combination of "bridge resonance" with N-functionalization. The enhanced mixing between the S1 state and CT/CS states results in direct observation of the CT band in the steady-state UV-vis absorption and negative free energy of charge separation (ΔGCS) in both chloroform and toluene for the two trimers. Using transient absorption spectroscopy, we demonstrated that photoinduced SB-CS in a nonpolar solvent is feasible. This work highlights that the use of "bridge resonance" is an effective way to control exciton dynamics of organic semiconductors.
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Affiliation(s)
- Kangwei Wang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Guangwei Shao
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Shaoqian Peng
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Xiaoxiao You
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Xingyu Chen
- International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Jingwen Xu
- International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Huaxi Huang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China.,School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Huan Wang
- International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Di Wu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China.,School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Jianlong Xia
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China.,School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
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23
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Heavy atom-free triplet photosensitizer based on thermally activated delayed fluorescence material for NIR-to-blue triplet-triplet annihilation upconversion. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Accelerating symmetry-breaking charge separation in a perylenediimide trimer through a vibronically coherent dimer intermediate. Nat Chem 2022; 14:786-793. [PMID: 35469005 DOI: 10.1038/s41557-022-00927-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 03/10/2022] [Indexed: 11/08/2022]
Abstract
Understanding the photophysics and photochemistry of molecular π-stacked chromophores is important for utilizing them as functional photonic materials. However, these investigations have been mostly limited to covalent molecular dimers, which can only approximate the electronic and vibronic interactions present in the higher oligomers typical of functional organic materials. Here we show that a comparison of the excited-state dynamics of a covalent slip-stacked perylenediimide dimer (2) and trimer (3) provides fundamental insights into electronic state mixing and symmetry-breaking charge separation (SB-CS) beyond the dimer limit. We find that coherent vibronic coupling to high-frequency modes facilitates ultrafast state mixing between the Frenkel exciton (FE) and charge-transfer (CT) states. Subsequently, solvent fluctuations and interchromophore low-frequency vibrations promote CT character in the coherent FE/CT mixed state. The coherent FE/CT mixed state persists in 2, but, in 3, low-frequency vibronic coupling collapses the coherence, resulting in ultrafast SB-CS between the distal perylenediimide units.
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25
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Rehhagen C, Rather SR, Schwarz KN, Scholes GD, Lochbrunner S. The effect of intermolecular electronic coupling on the exciton dynamics in perylene red nanoparticles. Phys Chem Chem Phys 2022; 24:8695-8704. [PMID: 35373223 DOI: 10.1039/d1cp05375b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Understanding the transport mechanisms of electronic excitations in molecular systems is the basis for their application in light harvesting and opto-electronic devices. The exciton transfer properties depend pivotally on the intermolecular coupling and the latter on the supramolecular structure. In this work, organic nanoparticles of the perylene derivative Perylene Red are prepared with flash-precipitation under different conditions. We correlate their intermolecular couplings, optical spectra, quantum yields, emission lifetimes and their size and characterize their exciton dynamics upon excitation with ultrashort laser pulses by transient absorption spectroscopy. We find that the intermolecular coupling can be varied by changing the preparation conditions and thus the supramolecular structure. In contrast to the monomeric system, the generation of charge-transfer states is found after optical excitation of the nanoparticles. The time of the generation step is in the order of 100 ps and depends on the intermolecular coupling. The mobility of the originally excited excitons is determined from measurements with varying exciton density. To this end, we model the contribution of exciton-exciton annihilation to the exciton decay assuming three-dimensional incoherent diffusion. The extracted exciton diffusion constant of nanoparticles with stronger intermolecular coupling is found to be 0.17 nm2 ps-1 and thereby about ten times higher than in the particles with smaller coupling.
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Affiliation(s)
- Chris Rehhagen
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany.
| | | | - Kyra N Schwarz
- School of Chemistry, University of Melbourne, Parkville, VIC, 3010, Australia
| | | | - Stefan Lochbrunner
- Institute for Physics and Department of Life, Light and Matter, University of Rostock, 18051 Rostock, Germany.
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26
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Seetharaman S, Zink‐Lorre N, Gutiérrez‐Moreno D, Karr PA, Fernández‐Lázaro F, D'Souza F. Quadrupolar Ultrafast Charge Transfer in Diaminoazobenzene‐Bridged Perylenediimide Triads. Chemistry 2022; 28:e202104574. [DOI: 10.1002/chem.202104574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Sairaman Seetharaman
- Department of Chemistry University of North Texas 1155 Union Circle, #305070 Denton TX 76203-5017 USA
| | - Nathalie Zink‐Lorre
- Área de Química Orgánica Instituto de Bioingeniería Universidad Miguel Hernández Avda. de la Universidad s/n 03202 Elche Spain
| | - David Gutiérrez‐Moreno
- Área de Química Orgánica Instituto de Bioingeniería Universidad Miguel Hernández Avda. de la Universidad s/n 03202 Elche Spain
| | - Paul A. Karr
- Department of Physical Sciences and Mathematics Wayne State College Wayne Nebraska 68787 USA
| | - Fernando Fernández‐Lázaro
- Área de Química Orgánica Instituto de Bioingeniería Universidad Miguel Hernández Avda. de la Universidad s/n 03202 Elche Spain
| | - Francis D'Souza
- Department of Chemistry University of North Texas 1155 Union Circle, #305070 Denton TX 76203-5017 USA
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27
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He Y, Mao C, Duan M, Fan L, Wang X, Cai Y, Du M, Hu M, Hu P, Cheng Q, Hu X. Rescuing the solid-state fluorescence of perylene diimide dyes by host–guest isolation. Org Chem Front 2022. [DOI: 10.1039/d2qo01358d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A host molecule with an open and flexible backbone was synthesized and is capable of recognizing various perylene diimide dyes. The host exhibits unique universality in improving the solid-state fluorescence of perylene diimide dyes.
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Affiliation(s)
- Yanfeng He
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Caihong Mao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Mingwan Duan
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Linmeng Fan
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Xiaohan Wang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Yan Cai
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Min Du
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Minli Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Ping Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Qiuyu Cheng
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
| | - Xiaobo Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, P. R. China
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28
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Fish GC, Moreno-Naranjo JM, Billion A, Kratzert D, Hack E, Krossing I, Nüesch F, Moser JE. Critical role of H-aggregation for high-efficiency photoinduced charge generation in pristine pentamethine cyanine salts. Phys Chem Chem Phys 2021; 23:23886-23895. [PMID: 34651630 PMCID: PMC8549113 DOI: 10.1039/d1cp03251h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/08/2021] [Indexed: 11/21/2022]
Abstract
The mechanism of photoinduced symmetry-breaking charge separation in solid cyanine salts at the base of organic photovoltaic and optoelectronic devices is still debated. Here, we employ femtosecond transient absorption spectroscopy (TAS) to monitor the charge transfer processes occurring in thin films of pristine pentamethine cyanine (Cy5). Oxidized dye species are observed in Cy5-hexafluorophosphate salts upon photoexcitation, resulting from electron transfer from monomer excited states to H-aggregates. The charge separation proceeds with a quantum yield of 86%, providing the first direct proof of high efficiency intrinsic charge generation in organic salt semiconductors. The impact of the size of weakly coordinating anions on charge separation and transport is studied using TAS alongside electroabsorption spectroscopy and time-of-flight techniques. The degree of H-aggregation decreases with increasing anion size, resulting in reduced charge transfer. However, there is little change in carrier mobility, as despite the interchromophore distance increasing, the decrease in energetic disorder helps to alleviate the trapping of charges by H-aggregates.
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Affiliation(s)
- George C Fish
- Photochemical Dynamics Group, Institute of Chemical Sciences and Engineering, École polytechnique fédérale de Lausanne, Station 6, 1015 Lausanne, Switzerland.
| | - Juan Manuel Moreno-Naranjo
- Photochemical Dynamics Group, Institute of Chemical Sciences and Engineering, École polytechnique fédérale de Lausanne, Station 6, 1015 Lausanne, Switzerland.
| | - Andreas Billion
- Institut für Anorganische und Analytische Chemie, and Freiburger Materialforschungszentrum, Universität Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Daniel Kratzert
- Institut für Anorganische und Analytische Chemie, and Freiburger Materialforschungszentrum, Universität Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Erwin Hack
- Laboratory for Transport at Nanoscale Interfaces, Swiss Federal Laboratories for Materials Science and Technology, Empa, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie, and Freiburger Materialforschungszentrum, Universität Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Frank Nüesch
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology, Empa, Überlandstrasse 129, 8600 Dübendorf, Switzerland
- Institute of Materials, School of Engineering, École polytechnique fédérale de Lausanne, Station 12, 1015 Lausanne, Switzerland
| | - Jacques-E Moser
- Photochemical Dynamics Group, Institute of Chemical Sciences and Engineering, École polytechnique fédérale de Lausanne, Station 6, 1015 Lausanne, Switzerland.
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29
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Zink‐Lorre N, Seetharaman S, Gutiérrez‐Moreno D, Fernández‐Lázaro F, Karr PA, D'Souza F. Excited State Charge Separation in an Azobenzene-Bridged Perylenediimide Dimer - Effect of Photochemical Trans-Cis Isomerization. Chemistry 2021; 27:14996-15005. [PMID: 34405918 PMCID: PMC8596671 DOI: 10.1002/chem.202102903] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Indexed: 01/26/2023]
Abstract
Photoinduced charge transfer and separation events in a newly synthesized azobenzene-bridged perylenediimide-dimer (PDI-dimer) are demonstrated. Trans-to-cis conversion (∼50 % efficiency) from the initial trans PDI-dimer by 355 nm pulsed laser light, and its reversal, cis-to-trans, process by 435 nm laser light irradiation has been possible to accomplish. Efficient fluorescence quenching in the PDI-dimer, more so for the cis isomer was witnessed, and such quenching increased with increasing solvent polarity. DFT-calculated geometry and electronic structures helped in visualizing the charge transfer in the PDI-dimer in both isomeric forms, and also revealed certain degree of participation of the azobenzene entity in the charge transfer events. Femtosecond transient absorption spectral studies confirmed occurrence of both charge transfer followed by charge separation in the studied PDI-dimer in both trans and cis forms in polar solvents, and the evaluated time constants from Global target analysis revealed accelerated events in the cis PDI-dimer due to proximity effects. The present study offers key insights on the role of the azobenzene bridge, and the dimer geometry in governing the excited state charge transfer and separation in symmetrically linked PDI dimer.
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Affiliation(s)
- Nathalie Zink‐Lorre
- Área de Química Orgánica, Instituto de BioingenieríaUniversidad Miguel Hernández de ElcheAvda. de la Universidad s/n03202ElcheSpain
| | - Sairaman Seetharaman
- Department of ChemistryUniversity of North Texas1155 Union Circle, #305070DentonTX 76203-5017USA
| | - David Gutiérrez‐Moreno
- Área de Química Orgánica, Instituto de BioingenieríaUniversidad Miguel Hernández de ElcheAvda. de la Universidad s/n03202ElcheSpain
| | - Fernando Fernández‐Lázaro
- Área de Química Orgánica, Instituto de BioingenieríaUniversidad Miguel Hernández de ElcheAvda. de la Universidad s/n03202ElcheSpain
| | - Paul A. Karr
- Department of Physical Sciences and MathematicsWayne State College1111 Main StreetWayneNebraska68787USA
| | - Francis D'Souza
- Department of ChemistryUniversity of North Texas1155 Union Circle, #305070DentonTX 76203-5017USA
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30
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Li X, Yu J, Lu Z, Duan J, Fry HC, Gosztola DJ, Maindan K, Rajasree SS, Deria P. Photoinduced Charge Transfer with a Small Driving Force Facilitated by Exciplex-like Complex Formation in Metal-Organic Frameworks. J Am Chem Soc 2021; 143:15286-15297. [PMID: 34499503 DOI: 10.1021/jacs.1c06629] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Photoinduced charge transfer (PCT) is a key step in the light-harvesting (LH) process producing the redox equivalents for energy conversion. However, like traditional macromolecular donor-acceptor assemblies, most MOF-derived LH systems are designed with a large ΔG0 to drive PCT. To emulate the functionality of the reaction center of the natural LH complex that drives PCT within a pair of identical chromophores producing charge carriers with maximum potentials, we prepared two electronically diverse carboxy-terminated zinc porphyrins, BFBP(Zn)-COOH and TFP(Zn)-COOH, and installed them into the hexagonal pores of NU-1000 via solvent-assisted ligand incorporation (SALI), resulting in BFBP(Zn)@NU-1000 and TFP(Zn)@NU-1000 compositions. Varying the number of trifluoromethyl groups at the porphyrin core, we tuned the ground-state redox potentials of the porphyrins within ca. 0.1 V relative to that of NU-1000, defining a small ΔG0 for PCT. For BFBP(Zn)@NU-1000, the relative ground- and excited-state redox potentials of the components facilitate an energy transfer (EnT) from NU-1000* to BFBP(Zn), forming BFBP(Zn)S1* which entails a long-lived charge-separated complex formed through an exciplex-like [BFBP(Zn)S1*-TBAPy] intermediate. Various time-resolved spectroscopic data suggest that EnT from NU-1000* may not involve a fast Förster-like resonance energy transfer (FRET) but rather through a slow [NU-1000*-BFBP(Zn)] intermediate formation. In contrast, TFP(Zn)@NU-1000 displays an efficient EnT from NU-1000* to [TFP(Zn)-TBAPy], a complex that formed at the ground state through electronic interaction, and thereon showed the excited-state feature of [TFP(Zn)-TBAPy]*. The results will help to develop synthetic LHC systems that can produce long-lived photogenerated charge carriers with high potentials, i.e., high open-circuit voltage in photoelectrochemical setups.
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Affiliation(s)
- Xinlin Li
- School of Chemical and Biomolecular Science, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States
| | - Jierui Yu
- School of Chemical and Biomolecular Science, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States
| | - Zhiyong Lu
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,College of Mechanics and Materials, Hohai University, Nanjing 210098, P. R. China
| | - Jiaxin Duan
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - H Christopher Fry
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois 60439, United States
| | - David J Gosztola
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois 60439, United States
| | - Karan Maindan
- School of Chemical and Biomolecular Science, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States
| | - Sreehari Surendran Rajasree
- School of Chemical and Biomolecular Science, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States
| | - Pravas Deria
- School of Chemical and Biomolecular Science, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States
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31
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Alzola JM, Tcyrulnikov NA, Brown PJ, Marks TJ, Wasielewski MR, Young RM. Symmetry-Breaking Charge Separation in Phenylene-Bridged Perylenediimide Dimers. J Phys Chem A 2021; 125:7633-7643. [PMID: 34431674 DOI: 10.1021/acs.jpca.1c05100] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perylenediimides (PDIs) are important molecular building blocks that are being investigated for their applicability in optoelectronic technologies. Covalently linking multiple PDI acceptors at the 2,5,8,11 (headland) positions adjacent to the PDI carbonyl groups is reported to yield higher power conversion efficiencies in photovoltaic cells relative to PDI acceptors linked at the 1,6,7,12 (bay) positions. While the photophysical properties of PDIs linked via the bay positions have been investigated extensively, those linked at the headland positions have received far less attention. We showed previously that symmetry-breaking charge separation (SB-CS) in PDIs hold promise as a strategy for increasing photovoltaic efficiency. Here we use transient absorption and emission spectroscopies to investigate the competition between SB-CS, fluorescence, and internal conversion in three related PDI dimers linked at the headland positions with o-, m-, and p-phenylene moieties: o-PDI2, m-PDI2, and p-PDI2, respectively. It is found that o-PDI2 supports SB-CS yielding PDI•+-PDI•-, which is in equilibrium with the o-PDI2 first excited state in a polar solvent (CH2Cl2) while m-PDI2 and p-PDI2 exhibit accelerated internal conversion due to the motion of the linker along with subnanosecond intersystem crossing (ISC). Electronic coupling and structural dynamics are shown to play a significant role, with o-PDI2 being the only member of the series that exhibits significant through-bond interchromophore coupling. The pronounced o-PDI2 steric congestion prevents the free internal rotation that leads to rapid deactivation of the excited state in the other dimers.
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Affiliation(s)
- Joaquin M Alzola
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Nikolai A Tcyrulnikov
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Paige J Brown
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Tobin J Marks
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M Young
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
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32
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Sebastian E, Hariharan M. Null Exciton-Coupled Chromophoric Dimer Exhibits Symmetry-Breaking Charge Separation. J Am Chem Soc 2021; 143:13769-13781. [PMID: 34370481 DOI: 10.1021/jacs.1c05793] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A comprehensive understanding of the structure-property relationships in multichromophoric architectures has pushed the limits for developing robust photosynthetic mimics and molecular photovoltaics. The elusive phenomenon of null exciton splitting has gathered immense attention in recent years owing to the occurrence in unique chromophoric architectures and consequent emergent properties. Herein, we unveil the hitherto unobserved null exciton coupling assisted highly efficient photoinduced symmetry-breaking charge separation (SB-CS) in a Greek cross (+)-oriented spiro-conjugated perylenediimide dimer (Sp-PDI2). Quantum chemical calculations have rationalized the infrequent manifestation of null exciton coupling behavior in Sp-PDI2. Negligible contribution of long-range Coulombic and short-range charge-transfer mediated coupling renders a monomer-like spectroscopic signature for Sp-PDI2 in toluene. The Greek cross (+)-arranged Sp-PDI2 possesses a selective hole-transfer coupling, facilitating the ultrafast dissociation of null excitons and evolution of the charge-separated state in polar solvents. Radical cationic and anionic spectroscopic signatures were characterized by employing femtosecond transient absorption spectroscopy. The substantial hole transfer electronic coupling and lower activation energy barrier of Sp-PDI2 accelerated the charge separation rate. The rate of charge recombination (CR) markedly decelerated due to falling into the inverted region of the Marcus parabola, where the driving force of CR is larger than the total reorganization energy for CR. Hence, the ratio of the rates for SB-CS over CR of Sp-PDI2 exhibited an unprecedently high value of 2647 in acetonitrile. The current study provides impeccable evidence for the role of selective charge filtering in governing efficient SB-CS and thereby novel insights towards the design of biomimics and advanced functional materials.
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Affiliation(s)
- Ebin Sebastian
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram 695551, Kerala, India
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram 695551, Kerala, India
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33
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Kaul N, Lomoth R. The Carbene Cannibal: Photoinduced Symmetry-Breaking Charge Separation in an Fe(III) N-Heterocyclic Carbene. J Am Chem Soc 2021; 143:10816-10821. [PMID: 34264638 PMCID: PMC8397313 DOI: 10.1021/jacs.1c03770] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
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Photoinduced symmetry-breaking
charge separation (SB-CS) processes
offer the possibility of harvesting solar energy by electron transfer
between identical molecules. Here, we present the first case of direct
observation of bimolecular SB-CS in a transition metal complex, [FeIIIL2](PF6) (L = [phenyl(tris(3-methylimidazol-1-ylidene))borate]−). Photoexcitation of the complex in the visible region
results in the formation of a doublet ligand-to-metal charge transfer
(2LMCT) excited state (E0–0 = 2.13 eV), which readily reacts with the doublet ground state to
generate charge separated products, [FeIIL2]
and [FeIVL2]2+, with a measurable
cage escape yield. Known spectral signatures allow for unambiguous
identification of the products, whose formation and recombination
are monitored with transient absorption spectroscopy. The unusual
energetic landscape of [FeIIIL2]+, as reflected in its ground and excited state reduction potentials,
results in SB-CS being intrinsically exergonic (ΔGCS° ∼ −0.7 eV). This is in contrast
to most systems investigated in the literature, where ΔGCS° is close to zero, and the charge transfer
driven primarily by solvation effects. The study is therefore illustrative
for the utilization of the rich redox chemistry accessible in transition
metal complexes for the realization of SB-CS.
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Affiliation(s)
- Nidhi Kaul
- Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
| | - Reiner Lomoth
- Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-75120 Uppsala, Sweden
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Zhao X, O'Connor JP, Schultz JD, Bae YJ, Lin C, Young RM, Wasielewski MR. Temperature Tuning of Coherent Mixing between States Driving Singlet Fission in a Spiro-Fused Terrylenediimide Dimer. J Phys Chem B 2021; 125:6945-6954. [PMID: 34133180 DOI: 10.1021/acs.jpcb.1c02476] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The excited-state dynamics of a spiro-fused terrylene-3,4:11,12-bis(dicarboximide) (TDI) dimer (sTDI2) in toluene and 2-methyltetrahydrofuran (mTHF) were investigated as a function of temperature using femtosecond- and nanosecond-transient absorption spectroscopy, as well as two-dimensional electronic spectroscopy. The spiro conjugation and the corresponding geometry of this compound guarantee a short intermonomer distance along with a partial orbital overlap between the orthogonal TDI π-electron systems, providing electronic coupling between the TDIs. Photoexcitation of sTDI2 in toluene, a low dielectric solvent, at 295 K, results in the ultrafast formation of a state composed of a coherent mixture of singlet 1(S1S0), multiexciton 1(T1T1), and charge-transfer (CT) electronic characters. This mixed species decays to decorrelated triplet states on the nanosecond timescale, completing the process of intramolecular singlet fission (SF) in sTDI2. Upon decreasing the temperature from 295 to 200 K, the contribution of the 1(T1T1) state to the mixed species decreases concurrently with an increase in the CT state character. We attribute this behavior to the variation in the vibrational energy level alignment between the states comprising the mixture due to changes in the temperature and hence the local dielectric environment. In contrast, photoexcitation of sTDI2 in more polar mTHF at 295 K results in the formation of a mixed singlet and CT state before undergoing symmetry-breaking charge separation, owing to the increased stabilization of the CT state in the medium. However, in glassy mTHF at 85 K, photoexcited sTDI2 exhibits discernible multiexciton character, comparable to that observed in toluene at 200 K, which we rationalize by the similarity of the dielectric constants under these two sets of conditions. These observations of mixed states of varying diabatic contributions over the range of experimental conditions show that the temperature and the static dielectric constant can directly control the composition of the electronically mixed excited state of sTDI2 and thus the fate of the SF process.
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Affiliation(s)
- Xingang Zhao
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - James P O'Connor
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Jonathan D Schultz
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Youn Jue Bae
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Chenjian Lin
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M Young
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
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Bialas D, Kirchner E, Röhr MIS, Würthner F. Perspectives in Dye Chemistry: A Rational Approach toward Functional Materials by Understanding the Aggregate State. J Am Chem Soc 2021; 143:4500-4518. [DOI: 10.1021/jacs.0c13245] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- David Bialas
- Center for Nanosystems Chemistry, Universität Würzburg, Theodor-Boveri-Weg, 97074 Würzburg, Germany
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Eva Kirchner
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle I. S. Röhr
- Center for Nanosystems Chemistry, Universität Würzburg, Theodor-Boveri-Weg, 97074 Würzburg, Germany
| | - Frank Würthner
- Center for Nanosystems Chemistry, Universität Würzburg, Theodor-Boveri-Weg, 97074 Würzburg, Germany
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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