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Wang X, Gao S, Luo Y, Liu X, Tom R, Zhao K, Chang V, Marom N. Computational Discovery of Intermolecular Singlet Fission Materials Using Many-Body Perturbation Theory. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2024; 128:7841-7864. [PMID: 38774154 PMCID: PMC11103713 DOI: 10.1021/acs.jpcc.4c01340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/16/2024] [Accepted: 04/17/2024] [Indexed: 05/24/2024]
Abstract
Intermolecular singlet fission (SF) is the conversion of a photogenerated singlet exciton into two triplet excitons residing on different molecules. SF has the potential to enhance the conversion efficiency of solar cells by harvesting two charge carriers from one high-energy photon, whose surplus energy would otherwise be lost to heat. The development of commercial SF-augmented modules is hindered by the limited selection of molecular crystals that exhibit intermolecular SF in the solid state. Computational exploration may accelerate the discovery of new SF materials. The GW approximation and Bethe-Salpeter equation (GW+BSE) within the framework of many-body perturbation theory is the current state-of-the-art method for calculating the excited-state properties of molecular crystals with periodic boundary conditions. In this Review, we discuss the usage of GW+BSE to assess candidate SF materials as well as its combination with low-cost physical or machine learned models in materials discovery workflows. We demonstrate three successful strategies for the discovery of new SF materials: (i) functionalization of known materials to tune their properties, (ii) finding potential polymorphs with improved crystal packing, and (iii) exploring new classes of materials. In addition, three new candidate SF materials are proposed here, which have not been published previously.
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Affiliation(s)
- Xiaopeng Wang
- School
of Foundational Education, University of
Health and Rehabilitation Sciences, Qingdao 266113, China
- Qingdao
Institute for Theoretical and Computational Sciences, Institute of
Frontier and Interdisciplinary Science, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Siyu Gao
- Department
of Materials Science and Engineering, Carnegie
Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Yiqun Luo
- Department
of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Xingyu Liu
- Department
of Materials Science and Engineering, Carnegie
Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Rithwik Tom
- Department
of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Kaiji Zhao
- Department
of Materials Science and Engineering, Carnegie
Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Vincent Chang
- Department
of Materials Science and Engineering, Carnegie
Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Noa Marom
- Department
of Materials Science and Engineering, Carnegie
Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department
of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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2
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Jang YJ, Kim JH. Two-dimensional transition metal dichalcogenides as an emerging platform for singlet fission solar cells. Chem Asian J 2022; 17:e202200265. [PMID: 35644937 DOI: 10.1002/asia.202200265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/25/2022] [Indexed: 11/06/2022]
Abstract
Singlet fission, a rapid exciton doubling process via inverse Auger recombination, is recognized as one of the most practical and feasible means for overcoming the Shockley-Queisser limit. Singlet fission solar cells are generally developed by integrating photon downconversion organic semiconductors into conventional photovoltaic devices to break the maximum photovoltaic response of the host semiconductors by virtue of extra triplet excitons. In this regard, proper matching of two different semiconductors and heterointerface engineering are both crucial for highly efficient singlet fission solar cells. Therefore, the aim of this study is to review the prerequisite conditions for efficient triplet transfer at the heterointerfaces and thus highlight the robust spin and valley degrees of freedom of transition metal dichalcogenides with the ultimate goal of stimulating research into next-generation singlet fission solar cells.
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Affiliation(s)
- Yu Jin Jang
- Sungkyunkwan University, Convergence Research Center for Energy and Environmental Sciences, KOREA, REPUBLIC OF
| | - Ji-Hee Kim
- Sungkyunkwan University, Department of Energy Science, 2066 Seoburo, Jangangu, Suwon, KOREA, REPUBLIC OF
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3
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Triplet Energy Transfer between Inorganic Nanocrystals and Organic Molecules. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2022. [DOI: 10.1016/j.jpap.2022.100128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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4
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5
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Papadopoulos I, Gutiérrez-Moreno D, Bo Y, Casillas R, Greißel PM, Clark T, Fernández-Lázaro F, Guldi DM. Altering singlet fission pathways in perylene-dimers; perylene-diimide versus perylene-monoimide. NANOSCALE 2022; 14:5194-5203. [PMID: 35315470 DOI: 10.1039/d1nr08523a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We used a systematic approach to shed light on the inherent differences in perylenes, namely monoimides versus diimides, including coplanarity and dipole moment, and their impact on singlet fission (SF) by designing, synthesizing, and probing a full fledged series of phenylene- and naphthalene-linked dimers. Next to changing the functionality of the perylene core, we probed the effect of the spacers and their varying degrees of rotational freedom, molecular electrostatic potentials, and intramolecular interactions on the SF-mechanism and -efficiencies. An arsenal of spectroscopic techniques revealed that for perylene-monoimides, a strong charge-transfer mixing with the singlet and triplet excited states restricts SF and yields low triplet quantum yields. This is accompanied by an up-conversion channel that includes geminate triplet-triplet recombination. Using perylene-diimides alters the SF-mechanism by populating a charge-separated-state intermediate, which either favors or shuts-down SF. Napthylene-spacers bring about higher triplet quantum yields and overall better SF-performance for all perylene-monoimides and perylene-diimides. The key to better SF-performance is rotational freedom because it facilitates the overall excited-state polarization and amplifies intramolecular interactions between chromophores.
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Affiliation(s)
- Ilias Papadopoulos
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
| | - David Gutiérrez-Moreno
- Área de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Avda. de la Universidad s/n, 03203 Elche, Spain.
| | - Yifan Bo
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstr. 25, 91052 Erlangen, Germany
| | - Rubén Casillas
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstr. 25, 91052 Erlangen, Germany
| | - Phillip M Greißel
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
| | - Timothy Clark
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstr. 25, 91052 Erlangen, Germany
| | - Fernando Fernández-Lázaro
- Área de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Avda. de la Universidad s/n, 03203 Elche, Spain.
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
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6
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Zhang J, Sakai H, Suzuki K, Hasobe T, Tkachenko NV, Chang IY, Hyeon-Deuk K, Kaji H, Teranishi T, Sakamoto M. Near-Unity Singlet Fission on a Quantum Dot Initiated by Resonant Energy Transfer. J Am Chem Soc 2021; 143:17388-17394. [PMID: 34647732 DOI: 10.1021/jacs.1c04731] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The conversion of a high-energy photon into two excitons using singlet fission (SF) has stimulated a variety of studies in fields from fundamental physics to device applications. However, efficient SF has only been achieved in limited systems, such as solid crystals and covalent dimers. Here, we established a novel system by assembling 4-(6,13-bis(2-(triisopropylsilyl)ethynyl)pentacen-2-yl)benzoic acid (Pc) chromophores on nanosized CdTe quantum dots (QDs). A near-unity SF (198 ± 5.7%) initiated by interfacial resonant energy transfer from CdTe to surface Pc was obtained. The unique arrangement of Pc determined by the surface atomic configuration of QDs is the key factor realizing unity SF. The triplet-triplet annihilation was remarkably suppressed due to the rapid dissociation of triplet pairs, leading to long-lived free triplets. In addition, the low light-harvesting ability of Pc in the visible region was promoted by the efficient energy transfer (99 ± 5.8%) from the QDs to Pc. The synergistically enhanced light-harvesting ability, high triplet yield, and long-lived triplet lifetime of the SF system on nanointerfaces could pave the way for an unmatched advantage of SF.
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Affiliation(s)
- Jie Zhang
- Department of Chemistry, Graduate School of Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Katsuaki Suzuki
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, FI33720 Tampere, Finland
| | - I-Ya Chang
- Department of Chemistry, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - Kim Hyeon-Deuk
- Department of Chemistry, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - Hironori Kaji
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Toshiharu Teranishi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Masanori Sakamoto
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
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7
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Daiber B, van den Hoven K, Futscher MH, Ehrler B. Realistic Efficiency Limits for Singlet-Fission Silicon Solar Cells. ACS ENERGY LETTERS 2021; 6:2800-2808. [PMID: 34476299 PMCID: PMC8389984 DOI: 10.1021/acsenergylett.1c00972] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Singlet fission is a carrier multiplication mechanism that could make silicon solar cells much more efficient. The singlet-fission process splits one high-energy spin-singlet exciton into two lower-energy spin-triplet excitons. We calculated the efficiency potential of three technologically relevant singlet-fission silicon solar cell implementations. We assume realistic but optimistic parameters for the singlet-fission material and investigate the effect of singlet energy and entropic gain. If the transfer of triplet excitons occurs via charge transfer, the maximum efficiency is 34.6% at a surprisingly small singlet energy of 1.85 eV. For the Dexter-type triplet energy transfer, the maximum efficiency is 32.9% at a singlet energy of 2.15 eV. For Förster resonance energy transfer (FRET), the triplet excitons are first transferred into a quantum dot, from which they then undergo FRET into silicon. For this transfer mechanism, the maximum efficiency is 28.% at a singlet energy of 2.33 eV. We show that the efficiency gain from singlet fission is larger the more efficient the silicon base cell is, which stands in contrast to tandem perovskite-silicon solar cells.
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8
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Grassl F, Ullrich A, Mansour AE, Abdalbaqi SM, Koch N, Opitz A, Scheele M, Brütting W. Coupled Organic-Inorganic Nanostructures with Mixed Organic Linker Molecules. ACS APPLIED MATERIALS & INTERFACES 2021; 13:37483-37493. [PMID: 34328310 DOI: 10.1021/acsami.1c08614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The electronic properties of semiconducting inorganic lead sulfide (PbS) nanocrystals (NCs) and organic linker molecules are dependent on the size of NCs as well as the used ligands. Here, we demonstrate that a weakly binding ligand can be successfully attached to PbS NCs to form a coupled organic-inorganic nanostructure (COIN) by mixing with a strong binding partner. We use the weakly binding zinc β-tetraaminophthalocyanine (Zn4APc) in combination with the strongly binding 1,2-ethanedithiol (EDT) as a mixed ligand system and compare its structural, electronic, and (photo-)electrical properties with both single-ligand COINs. It is found that binding of Zn4APc is assisted by the presence of EDT leading to improved film homogeneity, lower trap density, and enhanced photocurrent of the derived devices. Thus, the mixing of ligands is a versatile tool to achieve COINs with improved performance.
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Affiliation(s)
- Florian Grassl
- Institut für Physik, Universität Augsburg, 86135 Augsburg, Germany
| | - Aladin Ullrich
- Institut für Physik, Universität Augsburg, 86135 Augsburg, Germany
| | - Ahmed E Mansour
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 12489 Berlin, Germany
| | | | - Norbert Koch
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 12489 Berlin, Germany
| | - Andreas Opitz
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Marcus Scheele
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, 72076 Tübingen, Germany
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9
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Manna B, Nandi A, Vats BG. Role of nanosize and defect trapping upon singlet fission yield and singlet fission dynamics of 1,6-Diphenyl-1,3,5-hexatriene nanoaggregates. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113262] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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10
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Manna B, Nandi A. Singlet fission in nanoaggregate of bis(phenylethynyl) derivative of benzene (BPEB): High energy triplet exciton generation with >100 % yield. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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11
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Kundu A, Dasgupta J. Photogeneration of Long-Lived Triplet States through Singlet Fission in Lycopene H-Aggregates. J Phys Chem Lett 2021; 12:1468-1474. [PMID: 33528257 DOI: 10.1021/acs.jpclett.0c03301] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Molecular triplet excitons produced through singlet fission (SF) usually have shorter triplet lifetimes due to exciton-exciton recombination and relaxation pathways, thereby resulting in complex device architectures for SF-boosted solar cells. Using broadband transient absorption spectroscopy, we here show that the photoexcitation of nanostructured lycopene H-aggregates at room temperature produces free triplets with an unprecedented 35-fold enhancement in the lifetime compared to those localized on the monomer backbone. The observed rise of a spectrally blue-shifted correlated T-T pair state in ∼19 ps with distinct vibronic features provides the basis for SF-induced triplet generation.
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Affiliation(s)
- Arup Kundu
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005, India
| | - Jyotishman Dasgupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005, India
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12
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Aguilar Suarez LE, de Graaf C, Faraji S. Influence of the crystal packing in singlet fission: one step beyond the gas phase approximation. Phys Chem Chem Phys 2021; 23:14164-14177. [PMID: 33988190 PMCID: PMC8284770 DOI: 10.1039/d1cp00298h] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Singlet fission (SF), a multiexciton generation process, has been proposed as an alternative to enhance the performance of solar cells. The gas phase dimer model has shown its utility to study this process, but it does not always cover all the physics and the effect of the surrounding atoms has to be included in such cases. In this contribution, we explore the influence of crystal packing on the electronic couplings, and on the so-called exciton descriptors and electron–hole correlation plots. We have studied three tetracene dimers extracted from the crystal structure, as well as several dimers and trimers of the α and β polymorphs of 1,3-diphenylisobenzofuran (DPBF). These polymorphs show different SF yields. Our results highlight that the character of the excited states of tetracene depends on both the mutual disposition of molecules and inclusion of the environment. The latter does however not change significantly the interpretation of the SF mechanism in the studied systems. For DPBF, we establish how the excited state analysis is able to pinpoint differences between the polymorphs. We observe strongly bound correlated excitons in the β polymorph which might hinder the formation of the 1TT state and, consequently, explain its low SF yield. Singlet fission (SF), a multiexciton generation process, has been proposed as an alternative to enhance the performance of solar cells.![]()
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Affiliation(s)
- Luis Enrique Aguilar Suarez
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
| | - Coen de Graaf
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands. and Department of Physical and Inorganic Chemistry, Universitat Rovira i Virgili, Campus Sescelades, C. Marcel lí Domingo 1, 43007 Tarragona, Spain and ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
| | - Shirin Faraji
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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Ribson RD, Choi G, Hadt RG, Agapie T. Controlling Singlet Fission with Coordination Chemistry-Induced Assembly of Dipyridyl Pyrrole Bipentacenes. ACS CENTRAL SCIENCE 2020; 6:2088-2096. [PMID: 33274285 PMCID: PMC7706079 DOI: 10.1021/acscentsci.0c01044] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Indexed: 05/28/2023]
Abstract
Singlet fission has the potential to surpass current efficiency limits in next-generation photovoltaics and to find use in quantum information science. Despite the demonstration of singlet fission in various materials, there is still a great need for fundamental design principles that allow for tuning of photophysical parameters, including the rate of fission and triplet lifetimes. Here, we describe the synthesis and photophysical characterization of a novel bipentacene dipyridyl pyrrole (HDPP-Pent) and its Li- and K-coordinated derivatives. HDPP-Pent undergoes singlet fission at roughly 50% efficiency (τSF = 730 ps), whereas coordination in the Li complex induces significant structural changes to generate a dimer, resulting in a 7-fold rate increase (τSF = 100 ps) and more efficient singlet fission with virtually no sacrifice in triplet lifetime. We thus illustrate novel design principles to produce favorable singlet fission properties, wherein through-space control can be achieved via coordination chemistry-induced multipentacene assembly.
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Affiliation(s)
- Ryan D. Ribson
- Division of Chemistry and
Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Gyeongshin Choi
- Division of Chemistry and
Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Ryan G. Hadt
- Division of Chemistry and
Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and
Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
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14
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Xue L, Song X, Feng Y, Cheng S, Lu G, Bu Y. General Dual-Switched Dynamic Singlet Fission Channels in Solvents Governed Jointly by Chromophore Structural Dynamics and Solvent Impact: Singlet Prefission Energetics Analyses. J Am Chem Soc 2020; 142:17469-17479. [DOI: 10.1021/jacs.0c06919] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lijuan Xue
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Xinyu Song
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Yiwei Feng
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Shibo Cheng
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Gang Lu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
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15
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Menon A, Papadopoulos I, Harreiß C, Mora-Fuentes JP, Cortizo-Lacalle D, Mateo-Alonso A, Spiecker E, Guldi DM. Collecting up to 115% of Singlet-Fission Products by Single-Walled Carbon Nanotubes. ACS NANO 2020; 14:8875-8886. [PMID: 32543172 DOI: 10.1021/acsnano.0c03668] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this contribution, we focused on integrating a phenylene-bridged dibenzodiazahexacene dimer (o-DAD), which is singlet fission (SF) active, onto single-walled carbon nanotubes (SWCNTs) as a low-energy sink for energetically low lying excited states that stem from SF. Spectroscopic and microscopic assays assisted in documenting that SWCNT/o-DAD feature high stability in THF as a result of electronic interactions between the individual constituents. For example, statistical Raman analysis underlined n-doping of SWCNTs in the presence of o-DAD. Fluorescence spectroscopy prompted an energy transfer between the individual constituents, a conclusion that was exclusively derived from the quenching of the o-DAD-centered fluorescence. Excitation spectroscopy with a focus on the SWCNT fluorescence confirmed independently this conclusion by showing o-DAD-centered features. Our work was rounded off by time-resolved transient absorption measurements with SWCNT/o-DAD, in which evidence was gathered for the sequential o-DAD-centered SF with an efficiency of 112% followed by a unidirectional energy transfer from o-DAD to SWCNT and a rapid deactivation. The energy transfer efficiency from SF products such as (S1S0)CT and 1(T1T1) exceeded the 100% threshold with values of 115%, which is conventionally found in energy transfer schemes.
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Affiliation(s)
- Arjun Menon
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-University Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen, Germany
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-University Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen, Germany
| | - Christina Harreiß
- Institute of Micro- and Nanostructure Research (IMN) & Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 3, 91058 Erlangen, Germany
| | - Juan P Mora-Fuentes
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain
| | - Diego Cortizo-Lacalle
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain
| | - Aurelio Mateo-Alonso
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 Donostia-San Sebastian, Spain
- Ikerbasque, Basque Foundation for Science, Maria Diaz de Haro 3, 6 Solairua, 48013 Bilbao, Spain
| | - Erdmann Spiecker
- Institute of Micro- and Nanostructure Research (IMN) & Center for Nanoanalysis and Electron Microscopy (CENEM) and Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 3, 91058 Erlangen, Germany
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-University Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen, Germany
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16
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Affiliation(s)
- Luis Enrique Aguilar Suarez
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
| | - Maximilian F. S. J. Menger
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
| | - Shirin Faraji
- Theoretical Chemistry Group, Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
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17
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Gray V, Allardice JR, Zhang Z, Dowland S, Xiao J, Petty AJ, Anthony JE, Greenham NC, Rao A. Direct vs Delayed Triplet Energy Transfer from Organic Semiconductors to Quantum Dots and Implications for Luminescent Harvesting of Triplet Excitons. ACS NANO 2020; 14:4224-4234. [PMID: 32181633 PMCID: PMC7199217 DOI: 10.1021/acsnano.9b09339] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/17/2020] [Indexed: 05/31/2023]
Abstract
Hybrid inorganic-organic materials such as quantum dots (QDs) coupled with organic semiconductors have a wide range of optoelectronic applications, taking advantage of the respective materials' strengths. A key area of investigation in such systems is the transfer of triplet exciton states to and from QDs, which has potential applications in the luminescent harvesting of triplet excitons generated by singlet fission, in photocatalysis and photochemical upconversion. While the transfer of energy from QDs to the triplet state of organic semiconductors has been intensely studied in recent years, the mechanism and materials parameters controlling the reverse process, triplet transfer to QDs, have not been well investigated. Here, through a combination of steady-state and time-resolved optical spectroscopy we study the mechanism and energetic dependence of triplet energy transfer from an organic ligand (TIPS-tetracene carboxylic acid) to PbS QDs. Over an energetic range spanning from exothermic (-0.3 eV) to endothermic (+0.1 eV) triplet energy transfer we find that the triplet energy transfer to the QD occurs through a single step process with a clear energy dependence that is consistent with an electron exchange mechanism as described by Marcus-Hush theory. In contrast, the reverse process, energy transfer from the QD to the triplet state of the ligand, does not show any energy dependence in the studied energy range; interestingly, a delayed formation of the triplet state occurs relative to the quantum dots' decay. Based on the energetic dependence of triplet energy transfer we also suggest design criteria for future materials systems where triplet excitons from organic semiconductors are harvested via QDs, for instance in light emitting structures or the harvesting of triplet excitons generated via singlet fission.
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Affiliation(s)
- Victor Gray
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
- Department
of Chemistry—Ångström Laboratory, Uppsala University, Box 523, 751 20 Uppsala, Sweden
| | - Jesse R. Allardice
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Zhilong Zhang
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Simon Dowland
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - James Xiao
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Anthony J. Petty
- Department
of Chemistry, University of Kentucky, 161 Jacobs Science Building, Lexington, Kentucky 40506-0174, United States
| | - John E. Anthony
- Department
of Chemistry, University of Kentucky, 161 Jacobs Science Building, Lexington, Kentucky 40506-0174, United States
| | - Neil C. Greenham
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Akshay Rao
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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18
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Duan R, Han G, Zeng Y, Peng Q, Yi Y. Suppressing triplet decay in quinoidal singlet fission materials: the role of molecular planarity and rigidity. Phys Chem Chem Phys 2020; 22:7546-7551. [PMID: 32219273 DOI: 10.1039/c9cp06987a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Singlet fission, in which one singlet exciton is split into two triplet excitons, provides the potential to exceed the Shockley-Queisser limit for the power conversion efficiencies of organic solar cells. However, the charge transfer from the triplet state is found to be slow in singlet fission materials, so suppression of the triplet decay is crucial for effective utilization of singlet fission. Here, we first investigated triplet decay for the singlet fission molecular materials of ThBF and TThBF, which are characteristic of twisted and flexible quinoidal backbones. It is found that these compounds show rapid nonradiative decay in the Franck-Condon region and through the T1/S0 crossing point. Interestingly, upon locking the backbone twist by methylene, the LThBF and LTThBF compounds exhibit much higher energy barriers from T1 to the T1/S0 crossing point, vanishing spin-orbit couplings, and decreased reorganization energies due to the planar and rigid structures. Consequently, both the triplet decay pathways are effectively suppressed. Our work reveals the importance of molecular planarity and rigidity in suppressing triplet decay and will be very helpful for full utilization of singlet fission in organic photovoltaics.
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Affiliation(s)
- Ruihong Duan
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
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19
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Daiber B, Pujari SP, Verboom S, Luxembourg SL, Tabernig SW, Futscher MH, Lee J, Zuilhof H, Ehrler B. A method to detect triplet exciton transfer from singlet fission materials into silicon solar cells: Comparing different surface treatments. J Chem Phys 2020; 152:114201. [PMID: 32199443 DOI: 10.1063/1.5139486] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Singlet fission is one of the most promising routes to overcome the single-junction efficiency limit for solar cells. Singlet fission-enhanced silicon solar cells are the most desirable implementation, but transfer of triplet excitons, the product of singlet fission, into silicon solar cells has proved to be very challenging. Here, we report on an all optical measurement technique for the detection of triplet exciton quenching at semiconductor interfaces, a necessary requirement for triplet exciton or charge transfer. The method relies on the growth of individual, single-crystal islands of the singlet fission material on the silicon surface. The islands have different heights, and we correlate these heights to the quenching efficiency of triplet excitons. The quenching efficiency is measured by spatially resolved delayed fluorescence and compared to a diffusion-quenching model. Using silicon capped with a blocking thermal oxide and aromatic monolayers, we demonstrate that this technique can quickly screen different silicon surface treatments for triplet exciton quenching.
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Affiliation(s)
- Benjamin Daiber
- AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Sidharam P Pujari
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Steven Verboom
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Stefan L Luxembourg
- TNO Energy Transition-Solar Energy, Westerduinweg 3, 1755 LE Petten, The Netherlands
| | - Stefan W Tabernig
- AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Moritz H Futscher
- AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Jumin Lee
- AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands
| | - Han Zuilhof
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Bruno Ehrler
- AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands
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20
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Robb AJ, Knorr ES, Watson N, Hanson K. Metal ion linked multilayers on mesoporous substrates: Energy/electron transfer, photon upconversion, and more. J Photochem Photobiol A Chem 2020. [DOI: 10.1016/j.jphotochem.2019.112291] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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21
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Kim VO, Broch K, Belova V, Chen YS, Gerlach A, Schreiber F, Tamura H, Della Valle RG, D'Avino G, Salzmann I, Beljonne D, Rao A, Friend R. Singlet exciton fission via an intermolecular charge transfer state in coevaporated pentacene-perfluoropentacene thin films. J Chem Phys 2019; 151:164706. [PMID: 31675857 DOI: 10.1063/1.5130400] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Singlet exciton fission is a spin-allowed process in organic semiconductors by which one absorbed photon generates two triplet excitons. Theory predicts that singlet fission is mediated by intermolecular charge-transfer states in solid-state materials with appropriate singlet-triplet energy spacing, but direct evidence for the involvement of such states in the process has not been provided yet. Here, we report on the observation of subpicosecond singlet fission in mixed films of pentacene and perfluoropentacene. By combining transient spectroscopy measurements to nonadiabatic quantum-dynamics simulations, we show that direct excitation in the charge-transfer absorption band of the mixed films leads to the formation of triplet excitons, unambiguously proving that they act as intermediate states in the fission process.
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Affiliation(s)
- Vincent O Kim
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Katharina Broch
- Fritz Haber Institute of the Max Planck Society, Department of Physical Chemistry, Faradayweg, 4-614195 Berlin, Germany
| | - Valentina Belova
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Y S Chen
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Alexander Gerlach
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Frank Schreiber
- Eberhard-Karls Universität Tübingen, Institut für Angewandte Physik, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Hiroyuki Tamura
- Department of Chemical System Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Raffaele Guido Della Valle
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna and INSTM-UdR Bologna, Viale Risorgimento 4, 40136 Bologna, Italy
| | - Gabriele D'Avino
- Institut Néel, CNRS and Grenoble Alpes University, F-38042 Grenoble, France
| | - Ingo Salzmann
- Department of Physics, Department of Chemistry and Biochemistry, Centre for Research in Molecular Modeling (CERMM), Centre for NanoScience Research (CeNSR), Concordia University, 7141 Sherbrooke St. West, Montreal, Quebec H4B 1R6, Canada
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, Department of Chemistry, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - Akshay Rao
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Richard Friend
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
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22
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Allardice JR, Thampi A, Dowland S, Xiao J, Gray V, Zhang Z, Budden P, Petty AJ, Davis NJLK, Greenham NC, Anthony JE, Rao A. Engineering Molecular Ligand Shells on Quantum Dots for Quantitative Harvesting of Triplet Excitons Generated by Singlet Fission. J Am Chem Soc 2019; 141:12907-12915. [PMID: 31336046 PMCID: PMC7007228 DOI: 10.1021/jacs.9b06584] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
Singlet
fission is an exciton multiplication process in organic
molecules in which a photogenerated spin-singlet exciton is rapidly
and efficiently converted to two spin-triplet excitons. This process
offers a mechanism to break the Shockley–Queisser limit by
overcoming the thermalization losses inherent to all single-junction
photovoltaics. One of the most promising methods to harness the singlet
fission process is via the efficient extraction of the dark triplet
excitons into quantum dots (QDs) where they can recombine radiatively,
thereby converting high-energy photons to pairs of low-energy photons,
which can then be captured in traditional inorganic PVs such as Si.
Such a singlet fission photon multiplication (SF-PM) process could
increase the efficiency of the best Si cells from 26.7% to 32.5%,
breaking the Shockley–Queisser limit. However, there has been
no demonstration of such a singlet fission photon multiplication (SF-PM)
process in a bulk system to date. Here, we demonstrate a solution-based
bulk SF-PM system based on the singlet fission material TIPS-Tc combined
with PbS QDs. Using a range of steady-state and time-resolved measurements
combined with analytical modeling we study the dynamics and mechanism
of the triplet harvesting process. We show that the system absorbs
>95% of incident photons within the singlet fission material to
form
singlet excitons, which then undergo efficient singlet fission in
the solution phase (135 ± 5%) before quantitative harvesting
of the triplet excitons (95 ± 5%) via a low concentration of
QD acceptors, followed by the emission of IR photons. We find that
in order to achieve efficient triplet harvesting it is critical to
engineer the surface of the QD with a triplet transfer ligand and
that bimolecular decay of triplets is potentially a major loss pathway
which can be controlled via tuning the concentration of QD acceptors.
We demonstrate that the photon multiplication efficiency is maintained
up to solar fluence. Our results establish the solution-based SF-PM
system as a simple and highly tunable platform to understand the dynamics
of a triplet energy transfer process between organic semiconductors
and QDs, one that can provide clear design rules for new materials.
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Affiliation(s)
- Jesse R Allardice
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Arya Thampi
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Simon Dowland
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - James Xiao
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Victor Gray
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom.,Department of Chemistry, Ångström Laboratory , Uppsala University , Box 532, Uppsala SE-751 20 , Sweden
| | - Zhilong Zhang
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Peter Budden
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - Anthony J Petty
- Center for Applied Energy Research , University of Kentucky , Research Park Drive , Lexington , Kentucky 40511 , United States
| | - Nathaniel J L K Davis
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom.,The MacDiarmid Institute for Advanced Materials and Nanotechnology, The Dodd-Walls Centre for Photonic and Quantum Technologies, School of Chemical and Physical Sciences , Victoria University of Wellington , Wellington 6140 , New Zealand
| | - Neil C Greenham
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
| | - John E Anthony
- Center for Applied Energy Research , University of Kentucky , Research Park Drive , Lexington , Kentucky 40511 , United States
| | - Akshay Rao
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge CB3 0HE , United Kingdom
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23
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Aggarwal N, Patnaik A. Dimeric conformation sensitive electronic excited states of tetracene congeners and their unconventional non-fluorescent behaviour. J CHEM SCI 2019. [DOI: 10.1007/s12039-019-1626-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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24
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Xie B, Fang W. Combined Quantum Trajectory Mean‐Field and Molecular Mechanical (QTMF/MM) Nonadiabatic Dynamics Simulations on the Photoinduced Ring‐Opening Reaction of 2(5H)‐Thiophenone. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900076] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Bin‐Bin Xie
- Hangzhou Institute of Advanced StudiesZhejiang Normal University 1108 Gengwen Road Hangzhou 311231, Zhejiang P. R. China
| | - Wei‐Hai Fang
- Hangzhou Institute of Advanced StudiesZhejiang Normal University 1108 Gengwen Road Hangzhou 311231, Zhejiang P. R. China
- Key Laboratory of Theoretical and Computational Photochemistry Ministry of Education College of ChemistryBeijing Normal University Beijing 100875 P. R. China
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25
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Nijjar P, Jankowska J, Prezhdo OV. Ehrenfest and classical path dynamics with decoherence and detailed balance. J Chem Phys 2019; 150:204124. [DOI: 10.1063/1.5095810] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Parmeet Nijjar
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Joanna Jankowska
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
- Faculty of Chemistry, University of Warsaw, Warsaw, 02-093, Poland
| | - Oleg V. Prezhdo
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
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26
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Willems RM, Meskers SCJ, Wienk MM, Janssen RAJ. Effect of Charge-Transfer State Energy on Charge Generation Efficiency via Singlet Fission in Pentacene-Fullerene Solar Cells. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2019; 123:10253-10261. [PMID: 31049121 PMCID: PMC6488139 DOI: 10.1021/acs.jpcc.9b00568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 03/24/2019] [Indexed: 06/01/2023]
Abstract
Singlet fission in pentacene creates two triplet excitons per absorbed photon. In a solar cell, each triplet can generate an electron-hole pair, and hence, external quantum efficiencies exceeding 100% have been reported for pentacene-fullerene solar cells. The energetics of this process are intriguing because the minimum photon energy loss, defined as the energy difference between the (triplet) exciton state and the open-circuit voltage, is less than 0.5 eV and distinctively smaller than that in most organic donor-acceptor solar cells. To investigate the energetics of this process, we analyze the effect of the energy of the lowest unoccupied molecular orbital (LUMO) for different fullerene derivatives. With the LUMO energy becoming less negative, the open-circuit voltage increases and charge generation decreases. For all but one of the fullerenes tested, the charge-transfer state energy is distinctively higher than the pentacene triplet energy, revealing that charge generation via singlet fission is actually endergonic. An elementary Marcus model for the rate of electron transfer provides a qualitative description of the experimental trends, in accordance with an endergonic charge transfer. Considering that charge generation from triplet states is endergonic, involvement of pentacene singlet states, either from direct photoexcitation or via triplet-triplet annihilation, cannot be excluded.
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Affiliation(s)
- Robin
E. M. Willems
- Molecular
Materials and Nanosystems and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Stefan C. J. Meskers
- Molecular
Materials and Nanosystems and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Martijn M. Wienk
- Molecular
Materials and Nanosystems and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - René A. J. Janssen
- Molecular
Materials and Nanosystems and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Dutch
Institute for Fundamental Energy Research, De Zaale 20, 5612
AJ Eindhoven, The Netherlands
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27
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Hu FQ, Zhao Q, Peng XB. Improved model on fluorescence decay in singlet fission materials. Phys Chem Chem Phys 2019; 21:2153-2165. [PMID: 30644475 DOI: 10.1039/c8cp06380j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Singlet fission (SF) materials are a kind of promising material for breaking the solar cell efficiency limit. Here we rebuild the four-electron spin Hamiltonian under our coordinate system and present an improved model described by the population evolution equations on fluorescence decay (FD) dynamics that contain several detailed physical processes. The improved model for total random molecular orientation gives a more consistent fitting on the experimental data [G. B. Piland et al., J. Phys. Chem. C, 2013, 117, 1224] about time-resolved FD of amorphous rubrene thin films in the presence of a strong magnetic field. The fitting can reflect the relative rates of the real physical processes. Further on, our results show two kinds of magnetic field effect for the variety of two molecular relative orientations with respect to each other and the magnetic field by investigating the singlet projection and FD dynamics of the system.
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Affiliation(s)
- Fang-Qi Hu
- Center for Quantum Technology Research, School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
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28
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Wang C, Kodaimati MS, Lian S, Weiss EA. Systematic control of the rate of singlet fission within 6,13-diphenylpentacene aggregates with PbS quantum dot templates. Faraday Discuss 2019; 216:162-173. [DOI: 10.1039/c8fd00157j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Perturbation of molecular packing and dielectric environment at a quantum dot surface can promote singlet fission in diphenylpentacene aggregates.
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Affiliation(s)
- Chen Wang
- Department of Chemistry and Biochemistry
- City University of New York
- Queens College
- Flushing
- USA
| | | | - Shichen Lian
- Department of Chemistry
- Northwestern University
- Evanston
- USA
| | - Emily A. Weiss
- Department of Chemistry
- Northwestern University
- Evanston
- USA
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29
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Reddy SR, Coto PB, Thoss M. Intramolecular Singlet Fission: Insights from Quantum Dynamical Simulations. J Phys Chem Lett 2018; 9:5979-5986. [PMID: 30257561 DOI: 10.1021/acs.jpclett.8b02674] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We investigate the dynamics of intramolecular singlet fission in a dimer consisting of two pentacene-based chromophores covalently bonded to a phenylene spacer using an approach that combines high-level ab initio multireference perturbation theory methods and quantum dynamical simulations. The results show that the population of the multiexcitonic state, corresponding to the first step of singlet fission, is facilitated by the existence of higher-lying doubly excited and charge transfer states that participate in a superexchange-like way. The important role played by high-frequency ring-breathing molecular vibrations in the process is also discussed.
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Affiliation(s)
- S Rajagopala Reddy
- Institute of Theoretical Physics and Interdisciplinary Center for Molecular Materials , Friedrich-Alexander University Erlangen-Nürnberg , 91058 Erlangen , Germany
| | - Pedro B Coto
- Institute of Theoretical Physics , Friedrich-Alexander-University Erlangen-Nürnberg , 91058 Erlangen , Germany
| | - Michael Thoss
- Institute of Physics , Albert-Ludwigs University Freiburg , 79104 Freiburg , Germany
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30
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Nagashima H, Kawaoka S, Akimoto S, Tachikawa T, Matsui Y, Ikeda H, Kobori Y. Singlet-Fission-Born Quintet State: Sublevel Selections and Trapping by Multiexciton Thermodynamics. J Phys Chem Lett 2018; 9:5855-5861. [PMID: 30227712 DOI: 10.1021/acs.jpclett.8b02396] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Singlet fission (SF) is expected to exceed the theoretical limit of the solar cell efficiency. Quintet (Q) state generation in triplet-triplet pair is essential for preventing the unwanted loss of SF-born multiexciton through singlet channels, although little is known on the primary multiexciton spin dynamics following the intermolecular SF. In this study, time-resolved EPR revealed the intermolecular multiexciton dynamics, energetics and geometries in aggregated 6,13-bis(triisopropylsilylethynyl)pentacene and 2-phenyl-6,11-bis(triisopropylsilylethynyl)tetracene in diluted frozen solution. We have demonstrated sublevel selective generations of excited quintet states (|Q0⟩, |Q-1⟩ and |Q-2⟩) by singlet-quintet (SQ) mixings during triplet-exciton diffusions within geminate multiexcitons. The present fundamental characteristics of the quintet generations shows strong impact of coexistence of molecularly ordered "hot spot" and disordered regions for exergonic SQ mixings driven by entropy, thereby paving a new avenue for rational designs of organic devices with controlled multiexciton dynamics by optimizing film morphologies.
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Affiliation(s)
- Hiroki Nagashima
- Molecular Photoscience Research Center , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
| | - Shuhei Kawaoka
- Department of Applied Chemistry, Graduate School of Engineering , Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku , Sakai , Osaka 599-8531 , Japan
| | - Seiji Akimoto
- Department of Chemistry, Graduate School of Science , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
| | - Takashi Tachikawa
- Molecular Photoscience Research Center , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
- Department of Chemistry, Graduate School of Science , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
| | - Yasunori Matsui
- Department of Applied Chemistry, Graduate School of Engineering , Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku , Sakai , Osaka 599-8531 , Japan
- The Research Institute for Molecular Electronic Devices , Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku , Sakai , Osaka 599-8531 , Japan
| | - Hiroshi Ikeda
- Department of Applied Chemistry, Graduate School of Engineering , Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku , Sakai , Osaka 599-8531 , Japan
- The Research Institute for Molecular Electronic Devices , Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku , Sakai , Osaka 599-8531 , Japan
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
- Department of Chemistry, Graduate School of Science , Kobe University , 1-1 Rokkodai-cho, Nada-ku , Kobe , Hyogo 657-8501 , Japan
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31
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Nagashima H, Kawaoka S, Matsui Y, Tachikawa T, Ikeda H, Kobori Y. Time-Resolved EPR Study on Singlet-Fission Induced Quintet Generation and Subsequent Triplet Dissociation in TIPS-Phenyl-Tetracene Aggregates. J PHOTOPOLYM SCI TEC 2018. [DOI: 10.2494/photopolymer.31.163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Hiroki Nagashima
- Laser Molecular Photoscience Laboratory, Molecular Photoscience Research Center, Kobe University
| | - Shuhei Kawaoka
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University
| | - Yasunori Matsui
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University
| | - Takashi Tachikawa
- Laser Molecular Photoscience Laboratory, Molecular Photoscience Research Center, Kobe University
- Department of Chemistry, Graduate School of Science, Kobe University
| | - Hiroshi Ikeda
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University
| | - Yasuhiro Kobori
- Laser Molecular Photoscience Laboratory, Molecular Photoscience Research Center, Kobe University
- Department of Chemistry, Graduate School of Science, Kobe University
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32
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Tempelaar R, Reichman DR. Vibronic exciton theory of singlet fission. I. Linear absorption and the anatomy of the correlated triplet pair state. J Chem Phys 2018; 146:174703. [PMID: 28477613 DOI: 10.1063/1.4982362] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Recent time-resolved spectroscopic experiments have indicated that vibronic coupling plays a vital role in facilitating the process of singlet fission. In this work, which forms the first article of a series, we set out to unravel the mechanisms underlying singlet fission through a vibronic exciton theory. We formulate a model in which both electronic and vibrational degrees of freedom are treated microscopically and non-perturbatively. Using pentacene as a prototypical material for singlet fission, we subject our theory to comparison with measurements on polarization-resolved absorption of single crystals, and employ our model to characterize the excited states underlying the absorption band. Special attention is given to the convergence of photophysical observables with respect to the basis size employed, through which we determine the optimal basis for more expensive calculations to be presented in subsequent work. We furthermore evaluate the energetic separation between the optically prepared singlet excited state and the correlated triplet pair state, as well as provide a real-space characterization of the latter, both of which are of key importance in the discussion of fission dynamics. We discuss our results in the context of recent experimental studies.
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Affiliation(s)
- Roel Tempelaar
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
| | - David R Reichman
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
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Abstract
Singlet fission is a photophysical reaction in which a singlet excited electronic state splits into two spin-triplet states. Singlet fission was discovered more than 50 years ago, but the interest in this process has gained a lot of momentum in the past decade due to its potential as a way to boost solar cell efficiencies. This review presents and discusses the most recent advances with respect to the theoretical and computational studies on the singlet fission phenomenon. The work revisits important aspects regarding electronic states involved in the process, the evaluation of fission rates and interstate couplings, the study of the excited state dynamics in singlet fission, and the advances in the design and characterization of singlet fission compounds and materials such as molecular dimers, polymers, or extended structures. Finally, the review tries to pinpoint some aspects that need further improvement and proposes future lines of research for theoretical and computational chemists and physicists in order to further push the understanding and applicability of singlet fission.
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Affiliation(s)
- David Casanova
- Kimika Fakultatea , Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC) , P.K. 1072, 20080 Donostia , Euskadi, Spain.,IKERBASQUE, Basque, Foundation for Science , 48013 Bilbao , Euskadi, Spain
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Pace NA, Arias DH, Granger DB, Christensen S, Anthony JE, Johnson JC. Dynamics of singlet fission and electron injection in self-assembled acene monolayers on titanium dioxide. Chem Sci 2018; 9:3004-3013. [PMID: 29732084 PMCID: PMC5915837 DOI: 10.1039/c7sc04688j] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/15/2018] [Indexed: 12/11/2022] Open
Abstract
We employ a combination of linear spectroscopy, electrochemistry, and transient absorption spectroscopy to characterize the interplay between electron transfer and singlet fission dynamics in polyacene-based dyes attached to nanostructured TiO2. For triisopropyl silylethynyl (TIPS)-pentacene, we find that the singlet fission time constant increases to 6.5 ps on a nanostructured TiO2 surface relative to a thin film time constant of 150 fs, and that triplets do not dissociate after they are formed. In contrast, TIPS-tetracene singlets quickly dissociate in 2 ps at the molecule/TiO2 interface, and this dissociation outcompetes the relatively slow singlet fission process. The addition of an alumina layer slows down electron injection, allowing the formation of triplets from singlet fission in 40 ps. However, the triplets do not inject electrons, which is likely due to a lack of sufficient driving force for triplet dissociation. These results point to the critical balance required between efficient singlet fission and appropriate energetics for interfacial charge transfer.
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Affiliation(s)
- Natalie A Pace
- National Renewable Energy Laboratory , Golden , CO 80401 , USA .
- Department of Chemistry and Biochemistry , University of Colorado , Boulder , CO 80309 , USA
| | - Dylan H Arias
- National Renewable Energy Laboratory , Golden , CO 80401 , USA .
| | - Devin B Granger
- Department of Chemistry , University of Kentucky , Lexington , KY 40506 , USA
| | | | - John E Anthony
- Department of Chemistry , University of Kentucky , Lexington , KY 40506 , USA
| | - Justin C Johnson
- National Renewable Energy Laboratory , Golden , CO 80401 , USA .
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35
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Davis NJLK, Allardice JR, Xiao J, Petty AJ, Greenham NC, Anthony JE, Rao A. Singlet Fission and Triplet Transfer to PbS Quantum Dots in TIPS-Tetracene Carboxylic Acid Ligands. J Phys Chem Lett 2018; 9:1454-1460. [PMID: 29506386 DOI: 10.1021/acs.jpclett.8b00099] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Singlet exciton fission allows for the generation of two triplet excitons for each photon absorbed within an organic semiconductor. Efficient harvesting of these triplets could allow for the Shockley-Queisser limit on the power conversion efficiency of single-junction photovoltaics to be broken. Here, we show that singlet fission molecules bound directly to PbS quantum dots as ligands can undergo singlet fission with near unity efficiency and can transfer triplets sequentially into the PbS with near unity efficiency. Within the PbS, the excitations recombine, giving rise of the emission of photons. This allows for the doubling of the quantum dot photoluminescence quantum efficiency when photons are absorbed by the singlet fission ligand, as compared to when directly absorbed in the quantum dot. Our approach demonstrates that it is possible to convert the exciton multiplication process of singlet fission into a photon multiplication process and provides a new path to harness singlet fission with photovoltaics.
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Affiliation(s)
- Nathaniel J L K Davis
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge , CB3 0HE , United Kingdom
| | - Jesse R Allardice
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge , CB3 0HE , United Kingdom
| | - James Xiao
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge , CB3 0HE , United Kingdom
| | - Anthony J Petty
- Department of Chemistry , University of Kentucky , 161 Jacobs Science Building , Lexington Kentucky 40506-0174 , United States
| | - Neil C Greenham
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge , CB3 0HE , United Kingdom
| | - John E Anthony
- Department of Chemistry , University of Kentucky , 161 Jacobs Science Building , Lexington Kentucky 40506-0174 , United States
| | - Akshay Rao
- Cavendish Laboratory , University of Cambridge , J. J. Thomson Avenue , Cambridge , CB3 0HE , United Kingdom
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36
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Ito S, Nagami T, Nakano M. Molecular design for efficient singlet fission. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2018. [DOI: 10.1016/j.jphotochemrev.2018.01.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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37
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Folie BD, Haber JB, Refaely-Abramson S, Neaton JB, Ginsberg NS. Long-Lived Correlated Triplet Pairs in a π-Stacked Crystalline Pentacene Derivative. J Am Chem Soc 2018; 140:2326-2335. [DOI: 10.1021/jacs.7b12662] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Jeffrey B. Neaton
- Kavli Energy NanoSciences Institute, Berkeley, California 94720, United States
| | - Naomi S. Ginsberg
- Kavli Energy NanoSciences Institute, Berkeley, California 94720, United States
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38
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Khatymova LZ, Kinzyabulatov RR, Khvostenko OG. Singlet and triplet transitions in UV absorption spectra of pentacene. HIGH ENERGY CHEMISTRY 2018. [DOI: 10.1134/s0018143918010058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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39
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Endothermic singlet fission is hindered by excimer formation. Nat Chem 2018; 10:305-310. [PMID: 29461531 DOI: 10.1038/nchem.2926] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 12/05/2017] [Indexed: 12/23/2022]
Abstract
Singlet fission is a process whereby two triplet excitons can be produced from one photon, potentially increasing the efficiency of photovoltaic devices. Endothermic singlet fission is desired for a maximum energy-conversion efficiency, and such systems have been considered to form an excimer-like state with multiexcitonic character prior to the appearance of triplets. However, the role of the excimer as an intermediate has, until now, been unclear. Here we show, using 5,12-bis((triisopropylsilyl)ethynyl)tetracene in solution as a prototypical example, that, rather than acting as an intermediate, the excimer serves to trap excited states to the detriment of singlet-fission yield. We clearly demonstrate that singlet fission and its conjugate process, triplet-triplet annihilation, occur at a longer intermolecular distance than an excimer intermediate would impute. These results establish that an endothermic singlet-fission material must be designed to avoid excimer formation, thus allowing singlet fission to reach its full potential in enhancing photovoltaic energy conversion.
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40
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Thampi A, Stern HL, Cheminal A, Tayebjee MJY, Petty AJ, Anthony JE, Rao A. Elucidation of Excitation Energy Dependent Correlated Triplet Pair Formation Pathways in an Endothermic Singlet Fission System. J Am Chem Soc 2018; 140:4613-4622. [PMID: 29275626 DOI: 10.1021/jacs.7b06274] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Singlet fission is the spin-allowed conversion of a photogenerated singlet exciton into two triplet excitons in organic semiconductors, which could enable single-junction photovoltaic cells to break the Shockley-Queisser limit. The conversion of singlets to free triplets is mediated by an intermediate correlated triplet pair (TT) state, but an understanding of how the formation and dissociation of these states depend on energetics and morphology is lacking. In this study, we probe the dynamics of TT states in a model endothermic fission system, TIPS-Tc nanoparticles, which show a mixture of crystalline and disordered regions. We observe the formation of different TT states, with varying yield and different rates of singlet decay, depending on the excitation energy. An emissive TT state is observed to grow in over 1 ns when excited at 480 nm, in contrast to excitation at lower energies where this emissive TT state is not observed. This suggests that the pathway for singlet fission in these nanoparticles is strongly influenced by the initial sub-100 fs relaxation of the photoexcited state away from the Franck-Condon point, with multiple possible TT states. On nanosecond time scales, the TT states are converted to free triplets, which suggests that TT states might diffuse into the disordered regions of the nanoparticles where their breakup to free triplets is favored. The free triplets then decay on μs time scales, despite the confined nature of the system. Our results provide important insights into the mechanism of endothermic singlet fission and the design of nanostructures to harness singlet fission.
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Affiliation(s)
- Arya Thampi
- Cavendish Laboratory , University of Cambridge , Cambridge CB3 0HE , U.K
| | - Hannah L Stern
- Cavendish Laboratory , University of Cambridge , Cambridge CB3 0HE , U.K
| | - Alexandre Cheminal
- Cavendish Laboratory , University of Cambridge , Cambridge CB3 0HE , U.K
| | - Murad J Y Tayebjee
- Cavendish Laboratory , University of Cambridge , Cambridge CB3 0HE , U.K
| | - Anthony J Petty
- University of Kentucky , Lexington , Kentucky 40506 , United States
| | - John E Anthony
- University of Kentucky , Lexington , Kentucky 40506 , United States
| | - Akshay Rao
- Cavendish Laboratory , University of Cambridge , Cambridge CB3 0HE , U.K
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41
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Abstract
A comprehensive overview of organic semiconductor crystals is provided, including the physicochemical features, the control of crystallization and the device physics.
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Affiliation(s)
- Chengliang Wang
- School of Optical and Electronic Information
- Huazhong University of Science and Technology
- Wuhan 430074
- China
- Wuhan National Laboratory for Optoelectronics (WNLO)
| | - Huanli Dong
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
| | - Lang Jiang
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Organic Solids
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
| | - Wenping Hu
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
- Department of Chemistry
- School of Science
- Tianjin University
- Tianjin 300072
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42
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Lukman S, Richter JM, Yang L, Hu P, Wu J, Greenham NC, Musser AJ. Efficient Singlet Fission and Triplet-Pair Emission in a Family of Zethrene Diradicaloids. J Am Chem Soc 2017; 139:18376-18385. [DOI: 10.1021/jacs.7b10762] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Steven Lukman
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Institute of Materials Research and Engineering, Agency for Science Technology and Research (A*STAR), 2 Fusionoplis Way, Singapore 138634, Singapore
| | - Johannes M. Richter
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Le Yang
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Institute of Materials Research and Engineering, Agency for Science Technology and Research (A*STAR), 2 Fusionoplis Way, Singapore 138634, Singapore
| | - Pan Hu
- Department
of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Jishan Wu
- Institute of Materials Research and Engineering, Agency for Science Technology and Research (A*STAR), 2 Fusionoplis Way, Singapore 138634, Singapore
- Department
of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Neil C. Greenham
- Cavendish
Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Andrew J. Musser
- Department of Physics & Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
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43
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Khatymov RV, Muftakhov MV, Shchukin PV. Negative ions, molecular electron affinity and orbital structure of cata-condensed polycyclic aromatic hydrocarbons. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:1729-1741. [PMID: 28753734 DOI: 10.1002/rcm.7945] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 07/13/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Polycyclic aromatic hydrocarbons are molecules of ecological, astrochemical significance that find practical applications in organic electronics, photonics and the chemical synthesis of novel materials. The utility of these molecules often implies the occurrence of their ionized forms. Studies in the gas phase of elementary processes of energy-controlled interaction of molecules with low-energy electrons shed light on the mechanisms of transient negative ion formation and evolution. METHODS Experiments with the individual compounds representing homologous and/or isomeric series of cata-condensed polyaromatic hydrocarbons were carried out by means of negative ion mass spectrometry in the resonant electron capture mode. Literature data obtained by complementary techniques and theoretical quantum chemical methods (ab initio and density functional theory (DFT)) were invoked to treat the experimental observations. RESULTS Most polycyclic aromatic hydrocarbon (PAH) molecules form long-lived molecular negative ions when exposed to free electrons of thermal or epi-thermal energy, and no fragmentation is observed up to ca 5 eV. The lifetimes of such ions with respect to the spontaneous loss of extra-electron vary from tens of microseconds for angular and branched PAH molecules to milliseconds for linear ones, and correlate with the adiabatic electron affinity (EA) of molecules. Detailed analysis of the electronic (orbital) structure of the molecules made it possible to rationalize the relatively low EAs of angular and branched PAH compared with those of linear ones. CONCLUSIONS The obtained results contribute to the field of electron-molecule interactions and may be of importance for the better comprehension of the functioning of organic electronics, for the synthesis of relevant novel materials, and the development of efficient analytical methods capable of discriminating structural isomers.
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Affiliation(s)
- Rustem V Khatymov
- Institute of Molecule and Crystal Physics, Ufa Research Center of Russian Academy of Sciences, IМСР URC RAS, Prospekt Oktyabrya 151, Ufa, 450075, Russia
| | - Mars V Muftakhov
- Institute of Molecule and Crystal Physics, Ufa Research Center of Russian Academy of Sciences, IМСР URC RAS, Prospekt Oktyabrya 151, Ufa, 450075, Russia
| | - Pavel V Shchukin
- Institute of Molecule and Crystal Physics, Ufa Research Center of Russian Academy of Sciences, IМСР URC RAS, Prospekt Oktyabrya 151, Ufa, 450075, Russia
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44
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Breen I, Tempelaar R, Bizimana LA, Kloss B, Reichman DR, Turner DB. Triplet Separation Drives Singlet Fission after Femtosecond Correlated Triplet Pair Production in Rubrene. J Am Chem Soc 2017; 139:11745-11751. [PMID: 28763611 DOI: 10.1021/jacs.7b02621] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Singlet fission, a multistep molecular process in which one photon generates two triplet excitons, holds great technological promise. Here, by applying a combination of transient transmittance and two-dimensional electronic spectroscopy with 5 fs laser pulses, we resolve the full set of fission steps before the onset of spin dephasing. In addition to its role as a viable singlet fission material, single-crystalline rubrene is selected because its energetics and transition dipole alignment uniquely allow for the unambiguous identification of the various fission steps through their contributions to distinct spectroscopic features. The measurements reveal that the neighboring correlated triplet pair achieves its maximum population within 20 fs. Subsequent growth of the triplet signal on picosecond time scales is attributable to spatial separation of the triplets, proceeding nonadiabatically through weakly coupled but near-resonant states. As such, we provide evidence in crystalline rubrene for a singlet fission step that, until now, has not been convincingly observed.
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Affiliation(s)
- Ilana Breen
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - Roel Tempelaar
- Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States
| | - Laurie A Bizimana
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - Benedikt Kloss
- Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States
| | - David R Reichman
- Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States
| | - Daniel B Turner
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
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45
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Zhu T, Wan Y, Huang L. Direct Imaging of Frenkel Exciton Transport by Ultrafast Microscopy. Acc Chem Res 2017; 50:1725-1733. [PMID: 28678469 DOI: 10.1021/acs.accounts.7b00155] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Long-range transport of Frenkel excitons is crucial for achieving efficient molecular-based solar energy harvesting. Understanding of exciton transport mechanisms is important for designing materials for solar energy applications. One major bottleneck in unraveling of exciton transport mechanisms is the lack of direct measurements to provide information in both spatial and temporal domains, imposed by the combination of fast energy transfer (typically ≤1 ps) and short exciton diffusion lengths (typically ≤100 nm). This challenge requires developing experimental tools to directly characterize excitation energy transport, and thus facilitate the elucidation of mechanisms. To address this challenge, we have employed ultrafast transient absorption microscopy (TAM) as a means to directly image exciton transport with ∼200 fs time resolution and ∼50 nm spatial precision. By mapping population in spatial and temporal domains, such approach has unraveled otherwise obscured information and provided important parameters for testing exciton transport models. In this Account, we discuss the recent progress in imaging Frenkel exciton migration in molecular crystals and aggregates by ultrafast microscopy. First, we establish the validity of the TAM methods by imaging singlet and triplet exciton transport in a series of polyacene single crystals that undergo singlet fission. A new singlet-mediated triplet transport pathway has been revealed by TAM, resulting from the equilibrium between triplet and singlet exciton populations. Such enhancement of triplet exciton transport enables triplet excitons to migrate as singlet excitons and leads to orders of magnitude faster apparent triplet exciton diffusion rate in the picosecond and nanosecond time scales, favorable for solar cell applications. Next we discuss how information obtained by ultrafast microscopy can evaluate coherent effects in exciton transport. We use tubular molecular aggregates that could support large exciton delocalization sizes as a model system. The initial experiments measure exciton diffusion constants of 3-6 cm2 s-1, 3-5 times higher than the incoherent limit predicted by theory, suggesting that coherent effects play a role. In summary, combining ultrafast spectroscopic methods with microscopic techniques provides a direct approach for obtaining important parameters to unravel the underlying exciton transport mechanisms in molecular solids. We discuss future directions to bridge the gap in understanding of fundamental energy transfer theories to include coherent and incoherent effects. We are still in the infancy of ultrafast microscopy, and the vast potential is not limited to the systems discussed in this Account.
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Affiliation(s)
- Tong Zhu
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yan Wan
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Libai Huang
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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46
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Xia J, Sanders SN, Cheng W, Low JZ, Liu J, Campos LM, Sun T. Singlet Fission: Progress and Prospects in Solar Cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29. [PMID: 27973702 DOI: 10.1002/adma.201601652] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 08/07/2016] [Indexed: 05/12/2023]
Abstract
The third generation of photovoltaic technology aims to reduce the fabrication cost and improve the power conversion efficiency (PCE) of solar cells. Singlet fission (SF), an efficient multiple exciton generation (MEG) process in organic semiconductors, is one promising way to surpass the Shockley-Queisser limit of conventional single-junction solar cells. Traditionally, this MEG process has been observed as an intermolecular process in organic materials. The implementation of intermolecular SF in photovoltaic devices has achieved an external quantum efficiency of over 100% and demonstrated significant promise for boosting the PCE of third generation solar cells. More recently, efficient intramolecular SF has been reported. Intramolecular SF materials are modular and have the potential to overcome certain design constraints that intermolecular SF materials possess, which may allow for more facile integration into devices.
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Affiliation(s)
- Jianlong Xia
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
| | - Samuel N Sanders
- Department of Chemistry, Columbia University, New York, New York, 10027, United States
| | - Wei Cheng
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
| | - Jonathan Z Low
- Department of Chemistry, Columbia University, New York, New York, 10027, United States
| | - Jinping Liu
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, New York, 10027, United States
| | - Taolei Sun
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, China
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47
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Aggarwal N, Patnaik A. Unusual Nonemissive Behavior of Rubrene J-Aggregates: A Rare Violation. J Phys Chem B 2017; 121:3190-3201. [PMID: 28334526 DOI: 10.1021/acs.jpcb.7b02072] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Structure-property correlations in rubrene (RB) colloidal J-aggregates were unravelled by steady state and time-resolved spectroscopy in conjunction with excited state density functional calculations. The RB J-aggregate with a slippage angle θ = 30.4°, estimated from the monomeric transition dipole moment directions, exhibited a broad fwhm of 1073 cm-1 and a 5 nm red-shifted absorption band carrying a transition dipole moment (M⃗λagg = 1.80 D) almost equivalent to the monomeric dye (M⃗λmon = 1.89 D). A significantly low magnitude of exciton coupling energy, ΔEexc = -358 cm-1 for the rhombic-RB colloidal J-aggregates resulted owing to the weaker electronic communication between the largely separated RB subunits (r = 7.2 Å) and a restricted exciton delocalization over the RB J-dimer (N = 2). The RB J-dimer exhibited a perfect balance between the computed singlet (2.53 eV) and the triplet (1.29 eV) exciton energies for singlet fission (SF). Supporting this, the PL decay profile of the J-aggregates revealed a delayed fluorescence, substantiating triplet pair formation via SF. The experimental evidence for the long-lived triplet formation was furthermore confirmed by its transient absorption (T1 → TN) at 530 nm. Consequently, a high probability for SF and a low probability for triplet-triplet recombination, leading to a dramatic lowering in photoluminescence quantum yield from 0.172 down to 0.035 was noted. The electronic structure calculations for the RB J-dimer followed TD-DFT-M062X/6-31G+(d,p) level of theory following integral equation formalism polarizable continuum model (IEFPCM) in water. S1 excited state for RB J-dimer was carefully analyzed using integral overlap of electron and hole density distribution (ϕ) and the defined t-indexes along all three spatial directions, and was found to be of locally excited in character.
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Affiliation(s)
- Nikhil Aggarwal
- Colloid and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
| | - Archita Patnaik
- Colloid and Interface Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
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48
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Wang K, Murahari P, Yokoyama K, Lord JS, Pratt FL, He J, Schulz L, Willis M, Anthony JE, Morley NA, Nuccio L, Misquitta A, Dunstan DJ, Shimomura K, Watanabe I, Zhang S, Heathcote P, Drew AJ. Temporal mapping of photochemical reactions and molecular excited states with carbon specificity. NATURE MATERIALS 2017; 16:467-473. [PMID: 27941808 DOI: 10.1038/nmat4816] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 10/31/2016] [Indexed: 06/06/2023]
Abstract
Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump-probe spin spectroscopy (photo-μSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.
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Affiliation(s)
- K Wang
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
| | - P Murahari
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
| | - K Yokoyama
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
- ISIS Muon Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - J S Lord
- ISIS Muon Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - F L Pratt
- ISIS Muon Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - J He
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
| | - L Schulz
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
| | - M Willis
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
| | - J E Anthony
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, USA
| | - N A Morley
- Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK
| | - L Nuccio
- University of Fribourg, Department of Physics and Fribourg Centre for Nanomaterials, Chemin du Museé 3, CH-1700 Fribourg, Switzerland
| | - A Misquitta
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
| | - D J Dunstan
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
| | - K Shimomura
- Materials and Life Science Division, J-PARC Center, Tokai, Ibaraki 319-1195, Japan
| | - I Watanabe
- RIKEN-RAL, Nishina Centre, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - S Zhang
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
| | - P Heathcote
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End, London E1 4NS, UK
| | - A J Drew
- College of Physical Sciences and Technology, Sichuan University, Chengdu, Sichuan 610064, China
- School of Physics and Astronomy, Queen Mary University of London, Mile End, London E1 4NS, UK
- ISIS Muon Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
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49
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Lee S, Hwang D, Jung SI, Kim D. Electron Transfer from Triplet State of TIPS-Pentacene Generated by Singlet Fission Processes to CH 3NH 3PbI 3 Perovskite. J Phys Chem Lett 2017; 8:884-888. [PMID: 28169550 DOI: 10.1021/acs.jpclett.7b00072] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
To reveal the applicability of singlet fission processes in perovskite solar cell, we investigated electron transfer from TIPS-pentacene to CH3NH3PbI3 (MAPbI3) perovskite in film phase. Through the observation of the shorter fluorescence lifetime in TIPS-pentacene/MAPbI3 perovskite bilayer film (5 ns) compared with pristine MAPbI3 perovskite film (20 ns), we verified electron-transfer processes between TIPS-pentacene and MAPbI3 perovskite. Furthermore, the observation of singlet fission processes, a faster decay rate, TIPS-pentacene cations, and the analysis of kinetic profiles of the intensity ratio between 500 and 525 nm in the TA spectra of the TIPS-pentacene/MAPbI3 perovskite bilayer film indicate that electron transfer occurs from triplet state of TIPS-pentacene generated by singlet fission processes to MAPbI3 perovskite conduction band. We believe that our results can provide useful information on the design of solar cells sensitized by singlet fission processes and pave the way for new types of perovskite solar cells.
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Affiliation(s)
- Sangsu Lee
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University , Seoul 03722, Korea
| | - Daesub Hwang
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University , Seoul 03722, Korea
| | - Seok Il Jung
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University , Seoul 03722, Korea
| | - Dongho Kim
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University , Seoul 03722, Korea
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50
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Pazos-Outón LM, Lee JM, Futscher MH, Kirch A, Tabachnyk M, Friend RH, Ehrler B. A Silicon-Singlet Fission Tandem Solar Cell Exceeding 100% External Quantum Efficiency with High Spectral Stability. ACS ENERGY LETTERS 2017; 2:476-480. [PMID: 28261671 PMCID: PMC5330651 DOI: 10.1021/acsenergylett.6b00678] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/25/2017] [Indexed: 05/27/2023]
Abstract
After 60 years of research, silicon solar cell efficiency saturated close to the theoretical limit, and radically new approaches are needed to further improve the efficiency. The use of tandem systems raises this theoretical power conversion efficiency limit from 34% to 45%. We present the advantageous spectral stability of using voltage-matched tandem solar cells with respect to their traditional series-connected counterparts and experimentally demonstrate how singlet fission can be used to produce simple voltage-matched tandems. Our singlet fission silicon-pentacene tandem solar cell shows efficient photocurrent addition. This allows the tandem system to benefit from carrier multiplication and to produce an external quantum efficiency exceeding 100% at the main absorption peak of pentacene.
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Affiliation(s)
- Luis M. Pazos-Outón
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Ju Min Lee
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Moritz H. Futscher
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Anton Kirch
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Maxim Tabachnyk
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Richard H. Friend
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Bruno Ehrler
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
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