1
|
Greißel PM, Thiel D, Gotfredsen H, Chen L, Krug M, Papadopoulos I, Miskolzie M, Torres T, Clark T, Brøndsted Nielsen M, Tykwinski RR, Guldi DM. Intramolecular Triplet Diffusion Facilitates Triplet Dissociation in a Pentacene Hexamer. Angew Chem Int Ed Engl 2024; 63:e202315064. [PMID: 38092707 DOI: 10.1002/anie.202315064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Indexed: 01/26/2024]
Abstract
Triplet dynamics in singlet fission depend strongly on the strength of the electronic coupling. Covalent systems in solution offer precise control over such couplings. Nonetheless, efficient free triplet generation remains elusive in most systems, as the intermediate triplet pair 1 (T1 T1 ) is prone to triplet-triplet annihilation due to its spatial confinement. In the solid state, entropically driven triplet diffusion assists in the spatial separation of triplets, resulting in higher yields of free triplets. Control over electronic coupling in the solid state is, however, challenging given its sensitivity to molecular packing. We have thus developed a hexameric system (HexPnc) to enable solid-state-like triplet diffusion at the molecular scale. This system is realized by covalently tethering three pentacene dimers to a central subphthalocyanine scaffold. Transient absorption spectroscopy, complemented by theoretical structural optimizations and steady-state spectroscopy, reveals that triplet diffusion is indeed facilitated due to intramolecular cluster formation. The yield of free triplets in HexPnc is increased by a factor of up to 14 compared to the corresponding dimeric reference (DiPnc). Thus, HexPnc establishes crucial design aspects for achieving efficient triplet dissociation in strongly coupled systems by providing avenues for diffusive separation of 1 (T1 T1 ), while, concomitantly, retaining strong interchromophore coupling which preserves rapid formation of 1 (T1 T1 ).
Collapse
Affiliation(s)
- Phillip M Greißel
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Dominik Thiel
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Henrik Gotfredsen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
- Current address: Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, UK
| | - Lan Chen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Marcel Krug
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Mark Miskolzie
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Tomás Torres
- Department of Organic Chemistry, Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049, Madrid, Spain
- IMDEA Nanociencia, C/Faraday 9, Cantoblanco, 28049, Madrid, Spain
| | - Timothy Clark
- Department of Chemistry and Pharmacy &, Computer-Chemie-Center (CCC), Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Mogens Brøndsted Nielsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
| | - Rik R Tykwinski
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| |
Collapse
|
2
|
He G, Churchill EM, Parenti KR, Zhang J, Narayanan P, Namata F, Malkoch M, Congreve DN, Cacciuto A, Sfeir MY, Campos LM. Promoting multiexciton interactions in singlet fission and triplet fusion upconversion dendrimers. Nat Commun 2023; 14:6080. [PMID: 37770472 PMCID: PMC10539328 DOI: 10.1038/s41467-023-41818-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 09/20/2023] [Indexed: 09/30/2023] Open
Abstract
Singlet fission and triplet-triplet annihilation upconversion are two multiexciton processes intimately related to the dynamic interaction between one high-lying energy singlet and two low-lying energy triplet excitons. Here, we introduce a series of dendritic macromolecules that serve as platform to study the effect of interchromophore interactions on the dynamics of multiexciton generation and decay as a function of dendrimer generation. The dendrimers (generations 1-4) consist of trimethylolpropane core and 2,2-bis(methylol)propionic acid (bis-MPA) dendrons that provide exponential growth of the branches, leading to a corona decorated with pentacenes for SF or anthracenes for TTA-UC. The findings reveal a trend where a few highly ordered sites emerge as the dendrimer generation grows, dominating the multiexciton dynamics, as deduced from optical spectra, and transient absorption spectroscopy. While the dendritic structures enhance TTA-UC at low annihilator concentrations in the largest dendrimers, the paired chromophore interactions induce a broadened and red-shifted excimer emission. In SF dendrimers of higher generations, the triplet dynamics become increasingly dominated by pairwise sites exhibiting strong coupling (Type II), which can be readily distinguished from sites with weaker coupling (Type I) by their spectral dynamics and decay kinetics.
Collapse
Affiliation(s)
- Guiying He
- Department of Physics, Graduate Center, City University of New York, New York, NY, 10016, USA
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA
| | - Emily M Churchill
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Kaia R Parenti
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Jocelyn Zhang
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Pournima Narayanan
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
- Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - Faridah Namata
- KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, SE-100 44, Stockholm, Sweden
| | - Michael Malkoch
- KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, SE-100 44, Stockholm, Sweden
| | - Daniel N Congreve
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Angelo Cacciuto
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Matthew Y Sfeir
- Department of Physics, Graduate Center, City University of New York, New York, NY, 10016, USA.
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA.
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, NY, 10027, USA.
| |
Collapse
|
3
|
García-Fernández A, Kammlander B, Riva S, Kühn D, Svanström S, Rensmo H, Cappel UB. Interface Energy Alignment between Lead Halide Perovskite Single Crystals and TIPS-Pentacene. Inorg Chem 2023; 62:15412-15420. [PMID: 37712395 PMCID: PMC10523438 DOI: 10.1021/acs.inorgchem.3c01482] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Indexed: 09/16/2023]
Abstract
At present, there is a huge development in optoelectronic applications using lead halide perovskites. Considering that device performance is largely governed by the transport of charges across interfaces and, therefore, the interfacial electronic structure, fundamental investigations of perovskite interfaces are highly necessary. In this study, we use high-resolution soft X-ray photoelectron spectroscopy based on synchrotron radiation to explore the interfacial energetics for the molecular layer of TIPS-pentacene and lead halide perovskite single crystals. We perform ultrahigh vacuum studies on multiple thicknesses of an in situ formed interface of TIPS-pentacene with four different in situ cleaved perovskite single crystals (MAPbI3, MAPbBr3, FAPbBr3, and CsxFA1-xPbBryI3-y). Our findings reveal a substantial shift of the TIPS-pentacene energy levels toward higher binding energies with increasing thickness, while the perovskite energy levels remain largely unaffected regardless of their composition. These shifts can be interpreted as band bending in the TIPS-pentacene, and such effects should be considered when assessing the energy alignment at perovskite/organic transport material interfaces. Furthermore, we were able to follow a reorganization on the MAPbI3 surface with the transformation of the surface C 1s into bulk C 1s.
Collapse
Affiliation(s)
- Alberto García-Fernández
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH − Royal Institute of Technology, Stockholm100 44, Sweden
| | - Birgit Kammlander
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH − Royal Institute of Technology, Stockholm100 44, Sweden
| | - Stefania Riva
- Division
of X-ray Photon Science, Department of Physics and Astronomy, Uppsala University, Box 516,Uppsala751 20, Sweden
| | - Danilo Kühn
- Institute
Methods and Instrumentation for Synchrotron Radiation Research PSISRR, Helmholtz-Zentrum Berlin für Materialien und
Energie, Albert-Einstein-Straße 15, Berlin 12489, Germany
| | - Sebastian Svanström
- Division
of X-ray Photon Science, Department of Physics and Astronomy, Uppsala University, Box 516,Uppsala751 20, Sweden
| | - Håkan Rensmo
- Division
of X-ray Photon Science, Department of Physics and Astronomy, Uppsala University, Box 516,Uppsala751 20, Sweden
| | - Ute B. Cappel
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH − Royal Institute of Technology, Stockholm100 44, Sweden
| |
Collapse
|
4
|
Kim J, Teo HT, Hong Y, Liau YC, Yim D, Han Y, Oh J, Kim H, Chi C, Kim D. Leveraging Charge-Transfer Interactions in Through-Space-Coupled Pentacene Dendritic Oligomer for Singlet Exciton Fission. J Am Chem Soc 2023; 145:19812-19823. [PMID: 37656929 DOI: 10.1021/jacs.3c05660] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Singlet exciton fission in organic chromophores has received much attention during the past decade. Inspired by numerous spectroscopic studies in the solid state, there have been vigorous efforts to study singlet exciton fission dynamics in covalently bonded oligomers, which aims to investigate underlying mechanisms of this intriguing process in simplified model systems. In terms of through-space orbital interactions, however, most of covalently bonded pentacene oligomers studied so far fall into weakly interacting systems since they manifest chain-like structures based on various (non)conjugated linkers. Therefore, it remains as a compelling question to answer how through-space interactions in the solid state intervene this photophysical process since it is hypersensitive to displacements and orientations between neighboring chromophores. Herein, as one of experimental studies to answer this question, we introduced a tight-packing dendritic structure whose mesityl-pentacene constituents are coupled via moderate through-space orbital interactions. Based on the comparison with a suitably controlled dendritic structure, which is in a weak coupling regime, important mechanistic viewpoints are tackled such as configurational mixings between singlet, charge-transfer, and triplet pair states and the role of chromophore multiplication. We underscore that our through-space-coupled dendritic oligomer in a quasi-intermediate coupling regime provides a hint on the interplay of multiconfigurational excited-states, which might have drawn complexity in singlet exciton fission kinetics throughout numerous solid-state morphologies.
Collapse
Affiliation(s)
- Juno Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hao Ting Teo
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Yongseok Hong
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Yuan Cheng Liau
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Daniel Yim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Yi Han
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Juwon Oh
- Department of ICT Environmental Health System and Department of Chemistry, Soonchunhyang University, Asan 31538, Korea
| | - Hyungjun Kim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Chunyan Chi
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| |
Collapse
|
5
|
Geng P, Chen D, Shivarudraiah SB, Chen X, Guo L, Halpert JE. Carrier Dynamics of Efficient Triplet Harvesting in AgBiS 2 /Pentacene Singlet Fission Solar Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300177. [PMID: 36938855 PMCID: PMC10161067 DOI: 10.1002/advs.202300177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/16/2023] [Indexed: 05/06/2023]
Abstract
Singlet fission is a process by which an organic semiconductor is able to generate two triplet excitons from a single photon. If charges from the triplets can be successfully harvested without heavy losses in energy, then this process can enable a single-junction solar cell to surpass the Shockley-Queisser limit. While singlet fission processes are commonly observed in several materials, harvesting the resulting triplets is difficult and has been demonstrated with only a few transport materials. Here, transient absorption spectroscopy is used to investigate singlet fission and carrier transfer processes at the AgBiS2 /pentacene (AgBiS2 /Pc) heterojunction. The successful transfer of triplets from pentacene to AgBiS2 and the transfer of holes from AgBiS2 to pentacene is observed. Further singlet fission in pentacene by modifying the crystallinity of the pentacene layer and have fabricated the first singlet fission AgBiS2 /Pc solar cell is enhanced. Singlet fission devices exhibit higher external quantum efficiency compared with the control devices, and thus demonstrating the significant contribution of charges from the singlet fission process.
Collapse
Affiliation(s)
- Pai Geng
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, Hong Kong SAR
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, P. R. China
- Key Laboratory of Energy Conversion and Storage Technologies (Southern University of Science and Technology), Ministry of Education, Shenzhen, 518055, P. R. China
| | - Dezhang Chen
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, Hong Kong SAR
| | - Sunil B Shivarudraiah
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, Hong Kong SAR
| | - Xihan Chen
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, P. R. China
- SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, 518055, P. R. China
| | - Liang Guo
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, P. R. China
- Key Laboratory of Energy Conversion and Storage Technologies (Southern University of Science and Technology), Ministry of Education, Shenzhen, 518055, P. R. China
| | - Jonathan E Halpert
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, Hong Kong SAR
- Energy Institute, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, China
- State Key Laboratory on Advanced Displays and Optoelectronics Technologies, Department of Electronics and Computer Engineering, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, 999077, China
| |
Collapse
|
6
|
Unger F, Moretti L, Hausch J, Bredehoeft J, Zeiser C, Haug S, Tempelaar R, Hestand NJ, Cerullo G, Broch K. Modulating Singlet Fission by Scanning through Vibronic Resonances in Pentacene-Based Blends. J Am Chem Soc 2022; 144:20610-20619. [DOI: 10.1021/jacs.2c07237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Frederik Unger
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| | - Luca Moretti
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milan 20133, Italy
| | - Julian Hausch
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| | - Jona Bredehoeft
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| | - Clemens Zeiser
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| | - Sara Haug
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| | - Roel Tempelaar
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Nicholas J. Hestand
- Department of Natural and Applied Sciences, Evangel University, 1111 North Glenstone Avenue, Springfield, Missouri 65802, United States
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milan 20133, Italy
| | - Katharina Broch
- Institute for Applied Physics, University of Tuebingen, Auf der Morgenstelle 10, Tuebingen, 72076, Germany
| |
Collapse
|
7
|
Silori Y, Yadav A, Chawla S, De AK. Effect of nanoscale confinement on ultrafast dynamics of singlet fission in TIPS-pentacene. Chemphyschem 2022; 23:e202200454. [PMID: 35830606 DOI: 10.1002/cphc.202200454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/12/2022] [Indexed: 11/06/2022]
Abstract
Singlet fission (SF) is a phenomenon for the generation of a pair of triplet excitons from a singlet excited molecule interacting with another adjacent molecule in its ground electronic state. By increasing the effective number of charge carriers and reducing thermal dissipation of excess energy, SF is promised to enhance light-harvesting efficiency for photovoltaic applications. While SF has been extensively studied in thin films and crystals, the same has not been explored much within a confined medium. Here, we report the ultrafast SF dynamics of triisopropylsilylethynyl pentacene (TIPS-Pn) in micellar nanocavity of varying sizes (prepared from TX-100, CTAB, and SDS surfactants). The nanoparticle with a smaller size contains weakly coupled chromophores and is shown to be more efficient for SF followed by triplet generation as compared to the nanoparticles of larger size which contain strongly coupled chromophores and are less efficient due to the presence of singlet exciton traps. Through these studies, we delineate how a subtle interplay between short-range and long-range interaction among chromophores confined within nanoparticles, fine-tuned by the curvature of the micellar interface but irrespective of the nature of the micelle (cationic or anionic or neutral), play a crucial role in SF through and generation of triplets.
Collapse
Affiliation(s)
- Yogita Silori
- IISER Mohali: Indian Institute of Science Education and Research Mohali, Chemical Sciences, INDIA
| | - Anita Yadav
- IISER Mohali: Indian Institute of Science Education and Research Mohali, Chemical Sciences, INDIA
| | - Sakshi Chawla
- IISER Mohali: Indian Institute of Science Education and Research Mohali, Chemical Sciences, INDIA
| | - Arijit Kumar De
- Indian Institute of Science Education and Research Mohali, Chemical Sciences, Knowledge City, Sector 81, 140306, SAS Nagar,, INDIA
| |
Collapse
|
8
|
Pensack RD, Purdum GE, Mazza SM, Grieco C, Asbury JB, Anthony JE, Loo YL, Scholes GD. Excited-State Dynamics of 5,14- vs 6,13-Bis(trialkylsilylethynyl)-Substituted Pentacenes: Implications for Singlet Fission. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:9784-9793. [PMID: 35756579 PMCID: PMC9210346 DOI: 10.1021/acs.jpcc.2c00897] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 05/20/2022] [Indexed: 05/16/2023]
Abstract
Singlet fission is a process in conjugated organic materials that has the potential to considerably improve the performance of devices in many applications, including solar energy conversion. In any application involving singlet fission, efficient triplet harvesting is essential. At present, not much is known about molecular packing arrangements detrimental to singlet fission. In this work, we report a molecular packing arrangement in crystalline films of 5,14-bis(triisopropylsilylethynyl)-substituted pentacene, specifically a local (pairwise) packing arrangement, responsible for complete quenching of triplet pairs generated via singlet fission. We first demonstrate that the energetic condition necessary for singlet fission is satisfied in amorphous films of the 5,14-substituted pentacene derivative. However, while triplet pairs form highly efficiently in the amorphous films, only a modest yield of independent triplets is observed. In crystalline films, triplet pairs also form highly efficiently, although independent triplets are not observed because triplet pairs decay rapidly and are quenched completely. We assign the quenching to a rapid nonadiabatic transition directly to the ground state. Detrimental quenching is observed in crystalline films of two additional 5,14-bis(trialkylsilylethynyl)-substituted pentacenes with either ethyl or isobutyl substituents. Developing a better understanding of the losses identified in this work, and associated molecular packing, may benefit overcoming losses in solids of other singlet fission materials.
Collapse
Affiliation(s)
- Ryan D. Pensack
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Geoffrey E. Purdum
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Samuel M. Mazza
- Department
of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Christopher Grieco
- Department
of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - John B. Asbury
- Department
of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - John E. Anthony
- Department
of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Yueh-Lin Loo
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
- Andlinger
Center for Energy and the Environment, Princeton
University, Princeton, New Jersey 08544, United States
| | - Gregory D. Scholes
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
9
|
He G, Yablon LM, Parenti KR, Fallon KJ, Campos LM, Sfeir MY. Quantifying Exciton Transport in Singlet Fission Diblock Copolymers. J Am Chem Soc 2022; 144:3269-3278. [PMID: 35166107 DOI: 10.1021/jacs.1c13456] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Singlet fission (SF) is a mechanism of exciton multiplication in organic chromophores, which has potential to drive highly efficient optoelectronic devices. Creating effective device architectures that operate by SF critically depends on electronic interactions across multiple length scales─from individual molecules to interchromophore interactions that facilitate multiexciton dephasing and exciton diffusion toward donor-acceptor interfaces. Therefore, it is imperative to understand the underpinnings of multiexciton transport and interfacial energy transfer in multichromophore systems. Interestingly, block copolymers (BCPs) can be designed to control multiscale interactions by tailoring the nature of the building blocks, yet SF dynamics are not well understood in these macromolecules. Here, we designed diblock copolymers comprising an inherent energy cleft at the interface between a block with pendent pentacene chromophores and an additional block with pendent tetracene chromophores. The singlet and triplet energy offset between the two blocks creates a driving force for exciton transport along the BCP chain in dilute solution. Using time-resolved optical spectroscopy, we have quantified the yields of key energy transfer steps, including both singlet and triplet energy transfer processes across the pentacene-tetracene interface. From this modular BCP architecture, we correlate the energy transfer time scales and relative yields with the length of each block. The ability to quantify these energy transfer processes provides valuable insights into exciton transport at critical length scales between bulk crystalline systems and small-molecule dimers─an area that has been underexplored.
Collapse
Affiliation(s)
- Guiying He
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, United States.,Photonics Initiative, Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| | - Lauren M Yablon
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Kaia R Parenti
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Kealan J Fallon
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Matthew Y Sfeir
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, United States.,Photonics Initiative, Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Nakamura S, Sakai H, Fuki M, Kobori Y, Tkachenko NV, Hasobe T. Enthalpy-Entropy Compensation Effect for Triplet Pair Dissociation of Intramolecular Singlet Fission in Phenylene Spacer-Bridged Hexacene Dimers. J Phys Chem Lett 2021; 12:6457-6463. [PMID: 34236876 DOI: 10.1021/acs.jpclett.1c01430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hexacene (Hc) is highly promising for singlet fission (SF). However, the number of SFs in Hc is extremely limited. As far as Hc dimers in solution are concerned, there is no report on the observation of the dissociation process from a correlated triplet pair (TT) to an individual one. The emphasis in this study is on the first observation of the quantitative TT generation together with the orientation-dependent photophysical discussions for TT dissociation using para- and meta-phenyl-bridged Hc dimers. Moreover, the activation enthalpies of Hc dimers in TT dissociation are smaller than those of pentacene (Pc) dimers, whereas the relative entropic contributions for Gibbs free energy of activation are much larger than the enthalpic ones in both Hc and Pc dimers. This implies that the vibrational motions are responsible for the intramolecular conformation changes associated with the TT dissociation. Consequently, "enthalpy-entropy compensation" has a large impact on the rate constants and quantum yields.
Collapse
Affiliation(s)
- Shunta Nakamura
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Masaaki Fuki
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Nikolai V Tkachenko
- Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, 33101 Tampere, Finland
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| |
Collapse
|
12
|
Kato K, Teki Y. Photogenerated carrier dynamics of TIPS-pentacene films as studied by photocurrent and electrically detected magnetic resonance. Phys Chem Chem Phys 2021; 23:6361-6369. [PMID: 33439177 DOI: 10.1039/d0cp05125j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The carrier generation process and spin dynamics through photoexcitation in the vacuum vapour deposition film of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-Pn) were investigated by temperature dependence measurements of photocurrent and electrically detected magnetic resonance (EDMR). The EDMR signal was constructed from two components and showed a maximum at approximately 200 K. The temperature dependence was analysed using quantum mechanical simulation, assuming the carrier dynamics of the weakly coupled electron-hole pair (e-h pair). In addition, the analytical formula of photocurrent generation and EDMR signal intensity were also derived based on classical rate equations and used to understand the carrier dynamics. Through phase-shift analysis in quadrature detection of the EDMR signals, one of the two components was well analysed by using a narrow Lorentzian shape, and the other was by using a broad Gaussian.
Collapse
Affiliation(s)
- Ken Kato
- Division of Molecular Materials Science, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
| | | |
Collapse
|
13
|
Karlsson JKG, Atahan A, Harriman A, Tkachenko NV, Ward AD, Schaberle FA, Serpa C, Arnaut LG. Singlet Exciton Fission and Associated Enthalpy Changes with a Covalently Linked Bichromophore Comprising TIPS-Pentacenes Held in an Open Conformation. J Phys Chem A 2021; 125:1184-1197. [DOI: 10.1021/acs.jpca.0c09961] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joshua K. G. Karlsson
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Alparslan Atahan
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Anthony Harriman
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Nikolai V. Tkachenko
- Faculty of Engineering and Natural Sciences, Tampere University, Koereakoulunkatu 7, FIN-33720 Tampere, Finland
| | - Andrew D. Ward
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Didcot OX11 0FA, U.K
| | - Fabio A. Schaberle
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Carlos Serpa
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Luis G. Arnaut
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| |
Collapse
|
14
|
Zhang T, Rai D, Holmes RJ. Device-Based Probe of Triplet Exciton Diffusion in Singlet Fission Materials. J Phys Chem Lett 2021; 12:966-972. [PMID: 33464089 DOI: 10.1021/acs.jpclett.0c02825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Probing triplet transport in singlet fission materials can be challenging due to the presence of multiple diffusing species. We present a device-based method to measure the intrinsic triplet diffusion length (LD) in organic semiconductor thin films exhibiting singlet fission. Triplet states are optically injected into the singlet fission material of interest via energy transfer from an adjacent thin film characterized by strong spin-orbit coupling. Injected triplets migrate through the full thickness of the material before undergoing dissociation at a donor-acceptor interface. By modeling the ratio of injector and acceptor photocurrent as a function of layer thickness, the triplet LD is extracted separate from processes of unknown efficiency including singlet fission and diffusion. In considering three archetypical fission systems, a wide range is found for the triplet LD, ranging from 3.3 ± 0.4 nm for 5,12-bis((triisopropylsilyl)ethynyl)tetracene to 17.1 ± 1.3 nm for pentacene and 32.1 ± 2.6 nm for tetracene.
Collapse
Affiliation(s)
- Tao Zhang
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Deepesh Rai
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Russell J Holmes
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
15
|
Yoshino K, Sakai H, Shoji Y, Kajitani T, Anetai H, Akutagawa T, Fukushima T, Tkachenko NV, Hasobe T. Room-Temperature Pentacene Fluids: Oligoethylene Glycol Substituent-Controlled Morphologies and Singlet Fission. J Phys Chem B 2020; 124:11910-11918. [PMID: 33336576 DOI: 10.1021/acs.jpcb.0c09754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report the first synthesis of solvent-free pentacene fluids at room temperature together with observation of singlet fission (SF). Three pentacenes with different number of ethylene glycol (EG) side chains (n) were employed (denoted as (EG)n-Pc-(EG)n: n = 2, 3, and 4). The morphologies of these pentacenes largely depend on the lengths of EG chains (n). (EG)3-Pc-(EG)3 and (EG)4-Pc-(EG)4 indicate fluid compounds at room temperature, whereas (EG)2-Pc-(EG)2 is a solid compound. Microscopic clustering with short-range interactions between pentacene chromophores was confirmed in X-ray diffraction profiles of solvent-free fluids. Such a structural trend is an important origin of SF and consistent with the steady-state spectroscopic results. To one's surprise, femtosecond transient absorption spectroscopy demonstrated that SF occurred in thin films prepared from solvent-free fluids of (EG)3-Pc-(EG)3 and (EG)4-Pc-(EG)4 in spite of such excessive EG chains.
Collapse
Affiliation(s)
- Keisuke Yoshino
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| | - Yoshiaki Shoji
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.,RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Takashi Kajitani
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.,Materials Analysis Division, Open Facility Center, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Hayato Anetai
- Graduate School of Engineering, Tohoku University, Aoba-ku, Sendai 980-8578, Japan
| | - Tomoyuki Akutagawa
- Graduate School of Engineering, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.,Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Takanori Fukushima
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, Tampere FI33720, Finland
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| |
Collapse
|
16
|
Pace NA, Rugg BK, Chang CH, Reid OG, Thorley KJ, Parkin S, Anthony JE, Johnson JC. Conversion between triplet pair states is controlled by molecular coupling in pentadithiophene thin films. Chem Sci 2020; 11:7226-7238. [PMID: 34123008 PMCID: PMC8159287 DOI: 10.1039/d0sc02497j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 06/21/2020] [Indexed: 11/21/2022] Open
Abstract
In singlet fission (SF) the initially formed correlated triplet pair state, 1(TT), may evolve toward independent triplet excitons or higher spin states of the (TT) species. The latter result is often considered undesirable from a light harvesting perspective but may be attractive for quantum information sciences (QIS) applications, as the final exciton pair can be spin-entangled and magnetically active with relatively long room temperature decoherence times. In this study we use ultrafast transient absorption (TA) and time-resolved electron paramagnetic resonance (TR-EPR) spectroscopy to monitor SF and triplet pair evolution in a series of alkyl silyl-functionalized pentadithiophene (PDT) thin films designed with systematically varying pairwise and long-range molecular interactions between PDT chromophores. The lifetime of the (TT) species varies from 40 ns to 1.5 μs, the latter of which is associated with extremely weak intermolecular coupling, sharp optical spectroscopic features, and complex TR-EPR spectra that are composed of a mixture of triplet and quintet-like features. On the other hand, more tightly coupled films produce broader transient optical spectra but simpler TR-EPR spectra consistent with significant population in 5(TT)0. These distinctions are rationalized through the role of exciton diffusion and predictions of TT state mixing with low exchange coupling J versus pure spin substate population with larger J. The connection between population evolution using electronic and spin spectroscopies enables assignments that provide a more detailed picture of triplet pair evolution than previously presented and provides critical guidance for designing molecular QIS systems based on light-induced spin coherence.
Collapse
Affiliation(s)
- Natalie A Pace
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Brandon K Rugg
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Christopher H Chang
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Obadiah G Reid
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
- Renewable and Sustainable Energy Institute, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Karl J Thorley
- Department of Chemistry, University of Kentucky Lexington KY 40506 USA
| | - Sean Parkin
- 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 15013 Denver West Parkway Golden Colorado 80401 USA
| |
Collapse
|
17
|
Kwang SY, Frontiera RR. Spatially Offset Femtosecond Stimulated Raman Spectroscopy: Observing Exciton Transport through a Vibrational Lens. J Phys Chem Lett 2020; 11:4337-4344. [PMID: 32427490 DOI: 10.1021/acs.jpclett.0c01114] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To design better molecular electronic devices, we need a strong understanding of how charges or excitons propagate, as many efficiency losses arise during transport. Exciton transport has been difficult to study because excitons tend to be short-lived, have short diffusion lengths, and can easily recombine. Here, we debut spatially offset femtosecond stimulated Raman spectroscopy (SO-FSRS), a three-pulse ultrafast microscopy technique. By offsetting the photoexcitation beam, we can monitor Raman spectral changes as a function of both time and position. We used SO-FSRS on 6,13-bis(triisopropylsilylethynyl) pentacene, a well-studied organic semiconductor used in photovoltaics and field-effect transistors. We demonstrated that the fast exciton and free charge carrier transport axes are identical and observed that exciton transport is less anisotropic by a factor of ∼3. SO-FSRS is the first technique that directly tracks molecular structural evolution during exciton transport, which can provide roadmaps for tailor-making molecules for specific electronic devices.
Collapse
Affiliation(s)
- Siu Yi Kwang
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Renee R Frontiera
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
18
|
The Photophysical Properties of Triisopropylsilyl-ethynylpentacene—A Molecule with an Unusually Large Singlet-Triplet Energy Gap—In Solution and Solid Phases. CHEMISTRY-SWITZERLAND 2020. [DOI: 10.3390/chemistry2020033] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The process of singlet-exciton fission (SEF) has attracted much attention of late. One of the most popular SEF compounds is TIPS-pentacene (TIPS-P, where TIPS = triisopropylsilylethynyl) but, despite its extensive use as both a reference and building block, its photophysical properties are not so well established. In particular, the triplet state excitation energy remains uncertain. Here, we report quantitative data and spectral characterization for excited-singlet and -triplet states in dilute solution. The triplet energy is determined to be 7940 ± 1200 cm−1 on the basis of sensitization studies using time-resolved photoacoustic calorimetry. The triplet quantum yield at the limit of low concentration and low laser intensity is only ca. 1%. Self-quenching occurs at high solute concentration where the fluorescence yield and lifetime decrease markedly relative to dilute solution but we were unable to detect excimer emission by steady-state spectroscopy. Short-lived fluorescence, free from excimer emission or phosphorescence, occurs for crystals of TIPS-P, most likely from amorphous domains.
Collapse
|
19
|
Zukun W, Wu R, Chen Z, Ye L, Li H, Zhu H. Ultrafast Electron Transfer Before Singlet Fission and Slow Triplet State Electron Transfer in Pentacene Single Crystal/C 60 Heterostructure. J Phys Chem A 2020; 124:4185-4192. [PMID: 32353232 DOI: 10.1021/acs.jpca.0c01791] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The singlet fission (SF) process converts one high-energy singlet exciton to two low-energy triplet excitons after absorbing one photon. Organic photovoltaic devices based on the SF process have shown great potential in solar energy conversion to exceed Shockley-Queisser limit. The key to SF photovoltaic devices requires efficient electron transfer (ET) from triplet exciton after SF, which is yet to be thoroughly investigated. Here, we performed thorough photophysical studies in 6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene)/C60 heterostructures using TIPS-pentacene microsize single crystal as a well-defined model system. We show the SF process in TIPS-pentacene single crystal occurs by a two-step process, with triplet pair intermediates forming in 75 fs and then dissociating to non-interacting triplets in 1.6 ps. The SF process in single crystal is comparable to that in polycrystalline film. Importantly, we observe a considerable fraction of singlet excitons is quenched by ultrafast (<75 fs) interfacial ET prior to fission and no ET from triplet excitons in 1.5 ns time window. We confirm that the absence of ET is not limited by exciton diffusion but due to very slow (≫1.5 ns) interfacial ET from triplet exciton. The observations contradict expected singlet and triplet ET behaviors based on a simple two-state Marcus ET model and suggest long-range interfacial ET from delocalized photoexcitation. The ultrafast ET from singlet exciton before SF and slow ET from triplet exciton call for reconsideration and careful design of efficient SF photovoltaic devices.
Collapse
Affiliation(s)
- Wang Zukun
- Centre for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Ruihan Wu
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, State Key Laboratory of Silicon Materials, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, P. R. China
| | - Zeng Chen
- Centre for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Lei Ye
- Centre for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Hanying Li
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization, State Key Laboratory of Silicon Materials, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, P. R. China
| | - Haiming Zhu
- Centre for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, China
| |
Collapse
|
20
|
Spatial separation of triplet excitons drives endothermic singlet fission. Nat Chem 2020; 12:391-398. [PMID: 32123340 DOI: 10.1038/s41557-020-0422-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/14/2020] [Indexed: 11/08/2022]
Abstract
Molecules that undergo singlet fission, converting singlet excitons into pairs of triplet excitons, have potential as photovoltaic materials. The possible advantages of endothermic singlet fission (enhanced use of photon energy and larger triplet energies for coupling with common absorbers) motivated us to assess the role of exciton delocalization in the activation of this process. Here we report the synthesis of a series of linear perylene oligomers that undergo endothermic singlet fission and have endothermicities in the range 5-10 kBT at room temperature in solution. We study these compounds using transient spectroscopy and modelling to unravel the singlet and triplet dynamics. We show that the minimal number of coupled chromophores needed to undergo endothermic singlet fission is three, which provides sufficient statistical space for triplet excitons to separate and avoid annihilation-and a subsequent fast return to the singlet state. Our data additionally suggest that torsional motion of chromophores about the molecular axis following triplet-pair separation contributes to the increase in entropy, thus lengthening the triplet lifetime in longer oligomers.
Collapse
|
21
|
Matsuda S, Oyama S, Kobori Y. Electron spin polarization generated by transport of singlet and quintet multiexcitons to spin-correlated triplet pairs during singlet fissions. Chem Sci 2020; 11:2934-2942. [PMID: 34122794 PMCID: PMC8157521 DOI: 10.1039/c9sc04949e] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Singlet fission (SF) is expected to exceed the Shockley–Queisser theoretical limit of efficiency of organic solar cells. Transport of spin-entanglement in the triplet–triplet pair state via one singlet exciton is a promising phenomenon for several energy conversion applications including quantum information science. However, direct observation of electron spin polarization by transport of entangled spin-states has not been presented. In this study, time-resolved electron paramagnetic resonance has been utilized to observe the transportation of singlet and quintet characters generating correlated triplet–triplet (T + T) exciton-pair states by probing the electron spin polarization (ESP) generated in thin films of 6,13-bis(triisopropylsilylethynyl)pentacene. We have clearly demonstrated that the ESP detected at the resonance field positions of individual triplet excitons is dependent on the morphology and on the detection delay time after laser flash to cause SF. ESP was clearly explained by quantum superposition of singlet–triplet–quintet wavefunctions via picosecond triplet-exciton dissociation as the electron spin polarization transfer from strongly exchange-coupled singlet and quintet TT states to weakly-coupled spin-correlated triplet pair states. Although the coherent superposition of spin eigenstates was not directly detected, the present interpretation of the spin correlation of the separated T + T exciton pair may pave new avenues not only for elucidating the vibronic role in the de-coupling between two excitons but also for scalable quantum information processing using quick T + T dissociation via one-photon excitation. Singlet fission (SF) is expected to exceed the Shockley–Queisser theoretical limit of efficiency of organic solar cells.![]()
Collapse
Affiliation(s)
- Saki Matsuda
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
| | - Shinya Oyama
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
| | - Yasuhiro Kobori
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan .,Molecular Photoscience Research Center, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
| |
Collapse
|
22
|
Han J, Xie Q, Luo J, Deng GH, Qian Y, Sun D, Harutyunyan AR, Chen G, Rao Y. Anisotropic Geminate and Non-Geminate Recombination of Triplet Excitons in Singlet Fission of Single Crystalline Hexacene. J Phys Chem Lett 2020; 11:1261-1267. [PMID: 31971388 DOI: 10.1021/acs.jpclett.9b03800] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Singlet fission is believed to improve the efficiency of solar energy conversion by breaking up the Shockley-Queisser thermodynamic limit. Understanding of triplet excitons generated by singlet fission is essential for solar energy exploitation. Here we employed transient absorption microscopy to examine dynamical behaviors of triplet excitons. We observed anisotropic recombination of triplet excitons in hexacene single crystals. The triplet exciton relaxations from singlet fission proceed in both geminate and non-geminate recombination. For the geminate recombination, the different rates were attributed to the significant difference in their related energy change based on the Redfield quantum dissipation theory. The process is mainly governed by the electron-phonon interaction in hexacene. On the other hand, the non-geminate recombination is of bimolecular origin through energy transfer. In the triplet-triplet bimolecular process, the rates along the two different optical axes in the a-b crystalline plane differ by a factor of 4. This anisotropy in the triplet-triplet recombination rates was attributed to the interference in the coupling probability of dipole-dipole interactions in the different geometric configurations of hexacene single crystals. Our experimental findings provide new insight into future design of singlet fission materials with desirable triplet exciton exploitations.
Collapse
Affiliation(s)
- Jian Han
- School of Chemical Engineering , Nanjing University of Science and Technology , Nanjing 210094 , China
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Qing Xie
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Jun Luo
- School of Chemical Engineering , Nanjing University of Science and Technology , Nanjing 210094 , China
| | - Gang-Hua Deng
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Yuqin Qian
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Dezheng Sun
- Department of Physics , Columbia University , New York , New York 10027 , United States
| | - Avetik R Harutyunyan
- Honda Research Institute, USA, Inc. , San Jose , California 95134 , United States
| | - Gugang Chen
- Honda Research Institute, USA, Inc. , San Jose , California 95134 , United States
| | - Yi Rao
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| |
Collapse
|
23
|
Nelson TR, White AJ, Bjorgaard JA, Sifain AE, Zhang Y, Nebgen B, Fernandez-Alberti S, Mozyrsky D, Roitberg AE, Tretiak S. Non-adiabatic Excited-State Molecular Dynamics: Theory and Applications for Modeling Photophysics in Extended Molecular Materials. Chem Rev 2020; 120:2215-2287. [PMID: 32040312 DOI: 10.1021/acs.chemrev.9b00447] [Citation(s) in RCA: 179] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Optically active molecular materials, such as organic conjugated polymers and biological systems, are characterized by strong coupling between electronic and vibrational degrees of freedom. Typically, simulations must go beyond the Born-Oppenheimer approximation to account for non-adiabatic coupling between excited states. Indeed, non-adiabatic dynamics is commonly associated with exciton dynamics and photophysics involving charge and energy transfer, as well as exciton dissociation and charge recombination. Understanding the photoinduced dynamics in such materials is vital to providing an accurate description of exciton formation, evolution, and decay. This interdisciplinary field has matured significantly over the past decades. Formulation of new theoretical frameworks, development of more efficient and accurate computational algorithms, and evolution of high-performance computer hardware has extended these simulations to very large molecular systems with hundreds of atoms, including numerous studies of organic semiconductors and biomolecules. In this Review, we will describe recent theoretical advances including treatment of electronic decoherence in surface-hopping methods, the role of solvent effects, trivial unavoided crossings, analysis of data based on transition densities, and efficient computational implementations of these numerical methods. We also emphasize newly developed semiclassical approaches, based on the Gaussian approximation, which retain phase and width information to account for significant decoherence and interference effects while maintaining the high efficiency of surface-hopping approaches. The above developments have been employed to successfully describe photophysics in a variety of molecular materials.
Collapse
Affiliation(s)
- Tammie R Nelson
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Alexander J White
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Josiah A Bjorgaard
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Andrew E Sifain
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States.,U.S. Army Research Laboratory , Aberdeen Proving Ground , Maryland 21005 , United States
| | - Yu Zhang
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Benjamin Nebgen
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | | | - Dmitry Mozyrsky
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Adrian E Roitberg
- Department of Chemistry , University of Florida , Gainesville , Florida 32611 , United States
| | - Sergei Tretiak
- Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| |
Collapse
|
24
|
Korovina NV, Pompetti NF, Johnson JC. Lessons from intramolecular singlet fission with covalently bound chromophores. J Chem Phys 2020; 152:040904. [PMID: 32007061 DOI: 10.1063/1.5135307] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Molecular dimers, oligomers, and polymers are versatile components in photophysical and optoelectronic architectures that could impact a variety of applications. We present a perspective on such systems in the field of singlet fission, which effectively multiplies excitons and produces a unique excited state species, the triplet pair. The choice of chromophore and the nature of the attachment between units, both geometrical and chemical, play a defining role in the dynamical scheme that evolves upon photoexcitation. Specific final outcomes (e.g., separated and uncorrelated triplet pairs) are being sought through rational design of covalently bound chromophore architectures built with guidance from recent fundamental studies that correlate structure with excited state population flow kinetics.
Collapse
Affiliation(s)
- Nadezhda V Korovina
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
| | - Nicholas F Pompetti
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
| | - Justin C Johnson
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
| |
Collapse
|
25
|
Hudson RJ, de la Perrelle JM, Pensack RD, Kudisch B, Scholes GD, Huang DM, Kee TW. Organizing Crystalline Functionalized Pentacene Using Periodicity of Poly(Vinyl Alcohol). J Phys Chem Lett 2020; 11:516-523. [PMID: 31884794 DOI: 10.1021/acs.jpclett.9b03373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Nanoparticles of acenes exhibit highly efficient intermolecular singlet fission (SF). Recent reports indicate that altering the morphology of 6,13-bis-(triisopropylsilylethynyl)pentacene (TIPS-Pn) nanoparticles has a profound influence on their SF dynamics. Here, we show that poly(vinyl alcohol) (PVA) induces a phase transition in preformed TIPS-Pn nanoparticles. These nanoparticles are amorphous when initially formed but crystalline after addition of PVA. Surface characterization indicates that a diffuse PVA layer surrounds the nanoparticles. We propose that a periodic interaction between the hydroxyl groups of PVA and TIPS groups of TIPS-Pn on the nanoparticle surface induces a large-scale structural rearrangement to yield crystalline TIPS-Pn. Such reorganization in preformed organic nanoparticles is unprecedented, and we believe that this is the first report of such an effect induced by polymer adsorption. Transient absorption spectroscopic results reveal that SF within these nanoparticles is accelerated by an order of magnitude upon structural rearrangement.
Collapse
Affiliation(s)
- Rohan J Hudson
- Department of Chemistry , The University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Jessica M de la Perrelle
- Department of Chemistry , The University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Ryan D Pensack
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Bryan Kudisch
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Gregory D Scholes
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - David M Huang
- Department of Chemistry , The University of Adelaide , Adelaide , South Australia 5005 , Australia
| | - Tak W Kee
- Department of Chemistry , The University of Adelaide , Adelaide , South Australia 5005 , Australia
| |
Collapse
|
26
|
Jones AC, Kearns NM, Ho JJ, Flach JT, Zanni MT. Impact of non-equilibrium molecular packings on singlet fission in microcrystals observed using 2D white-light microscopy. Nat Chem 2019; 12:40-47. [PMID: 31792384 DOI: 10.1038/s41557-019-0368-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 10/08/2019] [Indexed: 11/09/2022]
Abstract
Singlet fission, the process of splitting a singlet exciton into two triplet excitons, has been proposed as a mechanism for improving the efficiency of future photovoltaic devices. In organic semiconductors exhibiting singlet fission, the geometric relationship between molecules plays an important role by setting the intermolecular couplings that determine the system energetics. Here, we spatially image TIPS-pentacene microcrystals using ultrafast two-dimensional white-light microscopy and discover a low-energy singlet state sparsely distributed throughout the microcrystals, with higher concentrations at edges and morphological defects. The spectra of these singlet states are consistent with slip-stacked molecular geometries and increased charge-transfer couplings. The picosecond-timescale kinetics of these low-energy singlet states matches that of the correlated triplet-pair state, which we attribute to singlet/triplet-pair interconversion at these sites. Our observations support the conclusion that small populations of geometries with favourable energetics can play outsized roles in singlet fission processes.
Collapse
Affiliation(s)
- Andrew C Jones
- Department of Chemistry, University of Wisconsin, Madison, WI, USA
| | | | - Jia-Jung Ho
- Department of Chemistry, University of Wisconsin, Madison, WI, USA
| | - Jessica T Flach
- Department of Chemistry, University of Wisconsin, Madison, WI, USA
| | - Martin T Zanni
- Department of Chemistry, University of Wisconsin, Madison, WI, USA.
| |
Collapse
|
27
|
Felter K, Grozema FC. Singlet Fission in Crystalline Organic Materials: Recent Insights and Future Directions. J Phys Chem Lett 2019; 10:7208-7214. [PMID: 31689105 PMCID: PMC6875870 DOI: 10.1021/acs.jpclett.9b00754] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 11/05/2019] [Indexed: 05/20/2023]
Abstract
Singlet fission (SF) involves the conversion of one excited singlet state into two lower excited triplet states and has received considerable renewed attention over the past decade. This Perspective highlights recent developments and emerging concepts of SF in solid-state crystalline materials. Recent experiments showed the crucial role of vibrational modes in speeding up SF, and theoretical modeling has started to define an optimal energetic landscape and intermolecular orientation of chromophores for highly efficient singlet fission. A critical analysis of these developments leads to directions for future research to eventually find singlet fission chromophores with excellent optoelectronic properties.
Collapse
Affiliation(s)
- Kevin
M. Felter
- Optoelectronic Materials
Section, Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HS Delft, The Netherlands
| | - Ferdinand C. Grozema
- Optoelectronic Materials
Section, Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HS Delft, The Netherlands
| |
Collapse
|
28
|
Grieco C, Doucette GS, Munson KT, Swartzfager JR, Munro JM, Anthony JE, Dabo I, Asbury JB. Vibrational probe of the origin of singlet exciton fission in TIPS-pentacene solutions. J Chem Phys 2019; 151:154701. [DOI: 10.1063/1.5116586] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Christopher Grieco
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Grayson S. Doucette
- Intercollege Materials Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Kyle T. Munson
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John R. Swartzfager
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Jason M. Munro
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John E. Anthony
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, USA
| | - Ismaila Dabo
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John B. Asbury
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Intercollege Materials Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| |
Collapse
|
29
|
Huang H, He G, Xu K, Wu Q, Wu D, Sfeir MY, Xia J. Achieving Long-Lived Triplet States in Intramolecular SF Films through Molecular Engineering. Chem 2019. [DOI: 10.1016/j.chempr.2019.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
30
|
Sanders SN, Pun AB, Parenti KR, Kumarasamy E, Yablon LM, Sfeir MY, Campos LM. Understanding the Bound Triplet-Pair State in Singlet Fission. Chem 2019. [DOI: 10.1016/j.chempr.2019.05.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
31
|
Lee TS, Lin YL, Kim H, Rand BP, Scholes GD. Two temperature regimes of triplet transfer in the dissociation of the correlated triplet pair after singlet fission. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0421] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ability to undergo spin-allowed exciton multiplication makes singlet fission materials promising for photovoltaic applications. Here, we examine the separation of correlated triplet pairs, 1(T…T), in polycrystalline pentacene films via temperature-dependent transient absorption spectroscopy. Single wavelength analysis reveals a profound delay in 1(T…T) dynamics. Moreover, the dynamics of 1(T…T) exhibit temperature dependence, whereas other features show no discernable temperature dependence. Previous literatures have suggested that correlated triplet separation is mediated by a thermally activated hopping process. Surprisingly, we found that the time constants governing triplet pair separation display two distinct temperature-dependent regimes of triplet transport. The high temperature regime follows a thermally activated hopping mechanism. The experimentally derived reorganization energy and electronic coupling is verified by density matrix renormalization group quantum chemical calculations. In addition, we evaluated the low temperature regime and show that the trend can be modelled by a Miller–Abrahams-type model that incorporates the effects of energetic disorder. We conclude that the correlated triplet pair separation is mediated by thermally activated hopping or a disorder driven Miller–Abrahams-type mechanism at high and low temperature, respectively. We observe that crossover between two regimes occurs ∼226 K. We find the time constant for triplet–triplet energy transfer to be 1.8 ps at ambient temperature and 21 ps at 77 K.
Collapse
Affiliation(s)
- Tia S. Lee
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - YunHui L. Lin
- Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Hwon Kim
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Barry P. Rand
- Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA
| | | |
Collapse
|
32
|
Efficient triplet pair separation from intramolecular singlet fission in dibenzopentalene derivatives. Sci China Chem 2019. [DOI: 10.1007/s11426-019-9482-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
33
|
Wu Y, Yu P, Chen Y, Zhao J, Liu H, Li Y, Wang J. Intensified C≡C Stretching Vibrator and Its Potential Role in Monitoring Ultrafast Energy Transfer in 2D Carbon Material by Nonlinear Vibrational Spectroscopy. J Phys Chem Lett 2019; 10:1402-1410. [PMID: 30848918 DOI: 10.1021/acs.jpclett.9b00027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this work, an intensity-enhanced C≡C stretching infrared (IR) absorption is observed in hexakis[(trimethylsilyl)ethynyl]benzene (HTEB), whose IR transition dipole magnitude becomes comparable to that of a typical C═O stretch, and the enhancement is believed to be due to a joint effect of π-π conjugation and hyperconjugation associated with a terminal trimethylsilyl group. Using dynamical time-dependent two-dimensional infrared (2D IR) spectroscopy, a picosecond intramolecular energy redistribution process is observed between two nondegenerate C≡C stretching modes, whose symmetry breaking is attributed to a noncovalent halogen-bonding interaction between HTEB and solvent CH2Cl2. The rigid structure of HTEB and limited structural dynamics are also inferred from the insignificant initial spectral diffusion value extracted from the 2D IR spectra. This work provides the first nonlinear infrared investigation of the conventionally weak C≡C stretch. The methods outlined are particularly important for detailed understanding of the structure-related processes such as vibrational energy transfer in novel C≡C species containing materials such as graphdiyne.
Collapse
Affiliation(s)
- Yanzhou Wu
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Pengyun Yu
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Yanhuan Chen
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Juan Zhao
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Huibiao Liu
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Yuliang Li
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Jianping Wang
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| |
Collapse
|
34
|
Wang Y, Qiu S, Xie S, Zhou L, Hong Y, Chang J, Wu J, Zeng Z. Synthesis and Characterization of Oxygen-Embedded Quinoidal Pentacene and Nonacene. J Am Chem Soc 2019; 141:2169-2176. [DOI: 10.1021/jacs.8b13884] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yanpei Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P.R. China
| | - Shuhai Qiu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P.R. China
| | - Sheng Xie
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P.R. China
| | - Long Zhou
- State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, Shaanxi Joint Key Laboratory of Graphene, School of Microelectronics, Xidian University, 2 South Taibai Road, Xi’an 710071, China
| | - Youhua Hong
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P.R. China
| | - Jingjing Chang
- State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, Shaanxi Joint Key Laboratory of Graphene, School of Microelectronics, Xidian University, 2 South Taibai Road, Xi’an 710071, China
| | - Jishan Wu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 Singapore
| | - Zebing Zeng
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P.R. China
| |
Collapse
|
35
|
Abstract
Building efficient triplet-harvesting layers for photovoltaic applications requires a deep understanding of the microscopic properties of the components involved and their dynamics. Singlet fission is a particularly appealing mechanism as it generates two excitons from a single photon. However, the pathways of the coupled triplets into free species, and their dependence on the intermolecular geometry, has not been fully explored. In this work, we produce highly ordered dilute pentacene films with distinct parallel and herringbone dimers and aggregates. Using electron paramagnetic resonance spectroscopy, we provide compelling evidence for the formation of distinct quintet excitons in ambient conditions, with intrinsically distinctive electronic and kinetic properties. We find that the ability of quintets to separate into free triplets is promoted in the parallel dimers and this provides molecular design rules to control the triplets, favouring either enhanced photovoltaic efficiency (parallel) or strongly bound pairs that could be exploited for logic applications (herringbone). Singlet fission results in the formation of a pair of triplets, known as a quintet. Here, the authors identify long-lived quintets in dilute pentacene films at room temperature, with lifetimes influenced by intermolecular geometry having implications for the design of triplet-harvesting films.
Collapse
|
36
|
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.
Collapse
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
| |
Collapse
|
37
|
Pensack RD, Tilley AJ, Grieco C, Purdum GE, Ostroumov EE, Granger DB, Oblinsky DG, Dean JC, Doucette GS, Asbury JB, Loo YL, Seferos DS, Anthony JE, Scholes GD. Striking the right balance of intermolecular coupling for high-efficiency singlet fission. Chem Sci 2018; 9:6240-6259. [PMID: 30090312 PMCID: PMC6062843 DOI: 10.1039/c8sc00293b] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/31/2018] [Indexed: 12/02/2022] Open
Abstract
Singlet fission is a process that splits collective excitations, or excitons, into two with unity efficiency. This exciton splitting process, unique to molecular photophysics, has the potential to considerably improve the efficiency of optoelectronic devices through more efficient light harvesting. While the first step of singlet fission has been characterized in great detail, subsequent steps critical to achieving overall highly-efficient singlet-to-triplet conversion are only just beginning to become well understood. One of the most elementary suggestions, which has yet to be tested, is that an appropriately balanced coupling is necessary to ensure overall highly efficient singlet fission; that is, the coupling needs to be strong enough so that the first step is fast and efficient, yet weak enough to ensure the independent behavior of the resultant triplets. In this work, we show how high overall singlet-to-triplet conversion efficiencies can be achieved in singlet fission by ensuring that the triplets comprising the triplet pair behave as independently as possible. We show that side chain sterics govern local packing in amorphous pentacene derivative nanoparticles, and that this in turn controls both the rate at which triplet pairs form and the rate at which they decay. We show how compact side chains and stronger couplings promote a triplet pair that effectively couples to the ground state, whereas bulkier side chains promote a triplet pair that appears more like two independent and long-lived triplet excitations. Our results show that the triplet pair is not emissive, that its decay is best viewed as internal conversion rather than triplet-triplet annihilation, and perhaps most critically that, in contrast to a number of recent suggestions, the triplets comprising the initially formed triplet pair cannot be considered independently. This work represents a significant step toward better understanding intermediates in singlet fission, and how molecular packing and couplings govern overall triplet yields.
Collapse
Affiliation(s)
- Ryan D Pensack
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA .
| | - Andrew J Tilley
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S 3H6 , Canada
| | - Christopher Grieco
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , USA
| | - Geoffrey E Purdum
- Department of Chemical and Biological Engineering , Princeton University , Princeton , New Jersey 08544 , USA
| | - Evgeny E Ostroumov
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA .
| | - Devin B Granger
- Department of Chemistry , University of Kentucky , Lexington , Kentucky 40506 , USA .
| | - Daniel G Oblinsky
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA .
| | - Jacob C Dean
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA .
| | - Grayson S Doucette
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , USA
| | - John B Asbury
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , USA
| | - Yueh-Lin Loo
- Department of Chemical and Biological Engineering , Princeton University , Princeton , New Jersey 08544 , USA
- Andlinger Center for Energy and the Environment , Princeton University , Princeton , New Jersey 08544 , USA
| | - Dwight S Seferos
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S 3H6 , Canada
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , Toronto , Ontario M5S 3E5 , Canada
| | - John E Anthony
- Department of Chemistry , University of Kentucky , Lexington , Kentucky 40506 , USA .
| | - Gregory D Scholes
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA .
| |
Collapse
|
38
|
Lee TS, Lin YL, Kim H, Pensack RD, Rand BP, Scholes GD. Triplet Energy Transfer Governs the Dissociation of the Correlated Triplet Pair in Exothermic Singlet Fission. J Phys Chem Lett 2018; 9:4087-4095. [PMID: 29976063 DOI: 10.1021/acs.jpclett.8b01834] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Singlet fission is a spin-allowed process of exciton multiplication that has the potential to enhance the efficiency of photovoltaic devices. The majority of studies to date have emphasized understanding the first step of singlet fission, where the correlated triplet pair is produced. Here, we examine separation of correlated triplet pairs. We conducted temperature-dependent transient absorption on 6,3-bis(tri isopropylsilylethynyl)pentacene (TIPS-Pn) films, where singlet fission is exothermic. We evaluated time constants to show that their temperature dependence is inconsistent with an exclusively thermally activated process. Instead, we found that the trends can be modeled by a triplet-triplet energy transfer. The fitted reorganization energy and electronic coupling agree closely with values calculated using density matrix renormalization group quantum-chemical theory. We conclude that dissociation of the correlated triplet pair to separated (but spin-entangled) triplet excitons in TIPS-Pn occurs by triplet-triplet energy transfer with a hopping time constant of approximately 3.5 ps at room temperature.
Collapse
Affiliation(s)
- Tia S Lee
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - YunHui L Lin
- Department of Electrical Engineering , Princeton University , Princeton , New Jersey 08544 , United States
| | - Hwon Kim
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Ryan D Pensack
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Barry P Rand
- Department of Electrical Engineering , Princeton University , Princeton , New Jersey 08544 , United States
- Andlinger Center for Energy and the Environment , Princeton University , Princeton , New Jersey 08544 , United States
| | - Gregory D Scholes
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| |
Collapse
|
39
|
Sakai H, Inaya R, Nagashima H, Nakamura S, Kobori Y, Tkachenko NV, Hasobe T. Multiexciton Dynamics Depending on Intramolecular Orientations in Pentacene Dimers: Recombination and Dissociation of Correlated Triplet Pairs. J Phys Chem Lett 2018; 9:3354-3360. [PMID: 29847939 DOI: 10.1021/acs.jpclett.8b01184] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Pentacene dimers bridged by a phenylene at ortho and meta positions [denoted as o-(Pc)2 and m-(Pc)2] were synthesized to examine intramolecular orientation-dependent multiexciton dynamics, especially focusing on singlet fission (SF) and recombination from correlated triplet pairs [(TT)]. Absorption and electrochemical measurements indicated strong intramolecular couplings of o-(Pc)2 relative to m-(Pc)2. Femtosecond and nanosecond TA measurements successfully demonstrated efficient SF in both dimers. In contrast, the dissociation process from the (TT) to the individual triplets [(2 × T)] was clearly observed in m-(Pc)2, which is in sharp contrast to a major recombination process in o-(Pc)2. Time-resolved electron spin resonance (TR-ESR) measurements demonstrated that the recombination and dissociation proceed from the quintet state of 5(TT) in m-(Pc)2. The rate constant of the SF was 2 orders of magnitude greater in o-(Pc)2 than that in m-(Pc)2 and was rationalized by enhanced electronic coupling between adjacent HOMOs of the Pc units.
Collapse
Affiliation(s)
- Hayato Sakai
- Department of Chemistry , Faculty of Science and Technology, Keio University , Yokohama 223-8522 , Japan
| | - Ryutaro Inaya
- Department of Chemistry , Faculty of Science and Technology, Keio University , Yokohama 223-8522 , Japan
| | - Hiroki Nagashima
- Molecular Photoscience Research Center , Kobe University , 1-1 Rokkodai-cho , Nada-ku, Kobe 657-8501 , Japan
| | - Shunta Nakamura
- Department of Chemistry , Faculty of Science and Technology, Keio University , Yokohama 223-8522 , Japan
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center , Kobe University , 1-1 Rokkodai-cho , Nada-ku, Kobe 657-8501 , Japan
- Department of Chemistry , Graduate School of Science, Kobe University , Kobe 657-8501 , Japan
| | - Nikolai V Tkachenko
- Laboratory of Chemistry and Bioengineering , Tampere University of Technology , 33720 Tampere , Finland
| | - Taku Hasobe
- Department of Chemistry , Faculty of Science and Technology, Keio University , Yokohama 223-8522 , Japan
| |
Collapse
|
40
|
Bender JA, Raulerson EK, Li X, Goldzak T, Xia P, Van Voorhis T, Tang ML, Roberts ST. Surface States Mediate Triplet Energy Transfer in Nanocrystal-Acene Composite Systems. J Am Chem Soc 2018; 140:7543-7553. [PMID: 29846066 DOI: 10.1021/jacs.8b01966] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Hybrid organic:inorganic materials composed of semiconductor nanocrystals functionalized with acene ligands have recently emerged as a promising platform for photon upconversion. Infrared light absorbed by a nanocrystal excites charge carriers that can pass to surface-bound acenes, forming triplet excitons capable of fusing to produce visible radiation. To fully realize this scheme, energy transfer between nanocrystals and acenes must occur with high efficiency, yet the mechanism of this process remains poorly understood. To improve our knowledge of the fundamental steps involved in nanoparticle:acene energy transfer, we used ultrafast transient absorption to investigate excited electronic dynamics of PbS nanocrystals chemically functionalized with 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) ligands. We find photoexcitation of PbS does not lead to direct triplet energy transfer to surface-bound TIPS-pentacene molecules but rather to the formation of an intermediate state within 40 ps. This intermediate persists for ∼100 ns before evolving to produce TIPS-pentacene triplet excitons. Analysis of transient absorption lineshapes suggests this intermediate corresponds to charge carriers localized at the PbS nanocrystal surface. This hypothesis is supported by constrained DFT calculations that find a large number of spin-triplet states at PbS NC surfaces. Though some of these states can facilitate triplet transfer, others serve as traps that hinder it. Our results highlight that nanocrystal surfaces play an active role in mediating energy transfer to bound acene ligands and must be considered when optimizing composite NC-based materials for photon upconversion, photocatalysis, and other optoelectronic applications.
Collapse
Affiliation(s)
- Jon A Bender
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| | - Emily K Raulerson
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| | - Xin Li
- Department of Chemistry , University of California Riverside , Riverside , California 92521 , United States
| | - Tamar Goldzak
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Pan Xia
- Materials Science & Engineering Program , University of California Riverside , Riverside , California 92521 , United States
| | - Troy Van Voorhis
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Ming Lee Tang
- Department of Chemistry , University of California Riverside , Riverside , California 92521 , United States.,Materials Science & Engineering Program , University of California Riverside , Riverside , California 92521 , United States
| | - Sean T Roberts
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| |
Collapse
|
41
|
Purdum GE, Telesz NG, Jarolimek K, Ryno SM, Gessner T, Davy NC, Petty AJ, Zhen Y, Shu Y, Facchetti A, Collis GE, Hu W, Wu C, Anthony JE, Weitz RT, Risko C, Loo YL. Presence of Short Intermolecular Contacts Screens for Kinetic Stability in Packing Polymorphs. J Am Chem Soc 2018; 140:7519-7525. [DOI: 10.1021/jacs.8b01421] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Geoffrey E. Purdum
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Nicholas G. Telesz
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Karol Jarolimek
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Sean M. Ryno
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | | | - Nicholas C. Davy
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Anthony J. Petty
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Yonggang Zhen
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Ying Shu
- Commonwealth Scientific and Industrial Research Organisation, Clayton South Victoria 3169, Australia
| | | | - Gavin E. Collis
- Commonwealth Scientific and Industrial Research Organisation, Clayton South Victoria 3169, Australia
| | - Wenping Hu
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chao Wu
- BASF SE, 67056 Ludwigshafen, Germany
| | - John E. Anthony
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | | | - Chad Risko
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Yueh-Lin Loo
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
42
|
Hetzer C, Guldi DM, Tykwinski RR. Pentacene Dimers as a Critical Tool for the Investigation of Intramolecular Singlet Fission. Chemistry 2018; 24:8245-8257. [DOI: 10.1002/chem.201705355] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Constantin Hetzer
- Department of Chemistry and Pharmacy; Interdisciplinary Center for Molecular Materials (ICMM); Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU); Nikolaus-Fiebiger-Straße 10 91058 Erlangen Germany
| | - Dirk M. Guldi
- Department of Chemistry and Pharmacy; Interdisciplinary Center for Molecular Materials (ICMM); Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU); Egerlandstrasse 3 91058 Erlangen Germany
| | - Rik R. Tykwinski
- Department of Chemistry; University of Alberta; Edmonton Alberta T6G 2G2 Canada
| |
Collapse
|
43
|
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
| |
Collapse
|
44
|
Grieco C, Kennehan ER, Rimshaw A, Payne MM, Anthony JE, Asbury JB. Harnessing Molecular Vibrations to Probe Triplet Dynamics During Singlet Fission. J Phys Chem Lett 2017; 8:5700-5706. [PMID: 29112418 DOI: 10.1021/acs.jpclett.7b02434] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Ultrafast vibrational spectroscopy in the mid-infrared spectral range provides the opportunity to probe the dynamics of electronic states involved in all stages of the singlet fission reaction through their unique vibrational frequencies. This capability is demonstrated using a model singlet fission chromophore, 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-Pn). The alkyne groups of the TIPS side chains are coupled to the conjugated framework of the pentacene cores, enabling direct examination of the dynamics of triplet excitons that have successfully separated from correlated triplet pair states in crystalline films of TIPS-Pn. Relaxation processes during the separation of triplet excitons and triplet-triplet annihilation after their separation result in the formation of hot ground state molecules that also exhibit unique vibrational frequencies. Because all organic molecules possess native vibrational modes, ultrafast vibrational spectroscopy offers a new approach to examine the dynamics of electronic intermediates that may inform ongoing efforts to utilize singlet fission to overcome thermalization losses in photovoltaic applications.
Collapse
Affiliation(s)
- Christopher Grieco
- Department of Chemistry, The Pennsylvania State University , State College, Pennsylvania 16801, United States
| | - Eric R Kennehan
- Department of Chemistry, The Pennsylvania State University , State College, Pennsylvania 16801, United States
| | - Adam Rimshaw
- Department of Chemistry, The Pennsylvania State University , State College, Pennsylvania 16801, United States
| | - Marcia M Payne
- Department of Chemistry, University of Kentucky , Lexington, Kentucky 40506, United States
| | - John E Anthony
- Department of Chemistry, University of Kentucky , Lexington, Kentucky 40506, United States
| | - John B Asbury
- Department of Chemistry, The Pennsylvania State University , State College, Pennsylvania 16801, United States
| |
Collapse
|
45
|
Dron PI, Michl J, Johnson JC. Singlet Fission and Excimer Formation in Disordered Solids of Alkyl-Substituted 1,3-Diphenylisobenzofurans. J Phys Chem A 2017; 121:8596-8603. [DOI: 10.1021/acs.jpca.7b07362] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Paul I. Dron
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Josef Michl
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Justin C. Johnson
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, United States
| |
Collapse
|
46
|
Yang F, Wang X, Fan H, Tang Y, Yang J, Yu J. Effect of In Situ Annealing Treatment on the Mobility and Morphology of TIPS-Pentacene-Based Organic Field-Effect Transistors. NANOSCALE RESEARCH LETTERS 2017; 12:503. [PMID: 28836186 PMCID: PMC6890873 DOI: 10.1186/s11671-017-2238-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 07/16/2017] [Indexed: 06/07/2023]
Abstract
In this work, organic field-effect transistors (OFETs) with a bottom gate top contact structure were fabricated by using a spray-coating method, and the influence of in situ annealing treatment on the OFET performance was investigated. Compared to the conventional post-annealing method, the field-effect mobility of OFET with 60 °C in situ annealing treatment was enhanced nearly four times from 0.056 to 0.191 cm2/Vs. The surface morphologies and the crystallization of TIPS-pentacene films were characterized by optical microscope, atomic force microscope, and X-ray diffraction. We found that the increased mobility was mainly attributed to the improved crystallization and highly ordered TIPS-pentacene molecules.
Collapse
Affiliation(s)
- Fuqiang Yang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, 610054 People’s Republic of China
- State Key Laboratory of Electronic Thin Films and Integrated Devices Zhongshan Branch Office, College of Electronic and Information Engineering, University of Electronic and Technology of China, Zhongshan Institute, Zhongshan, 528402 China
| | - Xiaolin Wang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, 610054 People’s Republic of China
| | - Huidong Fan
- State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, 610054 People’s Republic of China
| | - Ying Tang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, 610054 People’s Republic of China
| | - Jianjun Yang
- State Key Laboratory of Electronic Thin Films and Integrated Devices Zhongshan Branch Office, College of Electronic and Information Engineering, University of Electronic and Technology of China, Zhongshan Institute, Zhongshan, 528402 China
| | - Junsheng Yu
- State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, 610054 People’s Republic of China
| |
Collapse
|