1
|
Pino-Rios R, Báez-Grez R, Szczepanik DW, Solá M. Designing potentially singlet fission materials with an anti-Kasha behaviour. Phys Chem Chem Phys 2024; 26:15386-15392. [PMID: 38747026 DOI: 10.1039/d4cp01284d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Singlet fission (SF) compounds offer a promising avenue for improving the performance of solar cells. Using TD-DFT methods, anti-Kasha azulene derivatives that could carry out SF have been designed. For this purpose, substituted azulenes with a donor (-OH) and/or an acceptor group (-CN) have been systematically studied using the S2 ≥ 2T1 formula. We have found that -CN (-OH) substituents on electrophilic (nucleophilic) carbons result in improved SF properties when compared to azulene.
Collapse
Affiliation(s)
- Ricardo Pino-Rios
- Centro de Investigación Medicina de Altura - CEIMA, Universidad Arturo Prat. Casilla 121, Iquique 1100000, Chile.
- Química y Farmacia, Facultad de Ciencias de la Salud, Universidad Arturo Prat, Casilla 121, Iquique 1100000, Chile
| | - Rodrigo Báez-Grez
- Facultad de Ciencias, Universidad Arturo Prat, Casilla 121, Iquique 1100000, Chile
| | - Dariusz W Szczepanik
- K. Guminski Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, Poland
| | - Miquel Solá
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| |
Collapse
|
2
|
de Clercq DM, Collins MI, Sloane NP, Feng J, McCamey DR, Tayebjee MJY, Nielsen MP, Schmidt TW. Singlet fission in TIPS-anthracene thin films. Chem Sci 2024; 15:6402-6409. [PMID: 38699250 PMCID: PMC11062091 DOI: 10.1039/d3sc06774b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 03/24/2024] [Indexed: 05/05/2024] Open
Abstract
Singlet fission is an exciton multiplication process that allows for the conversion of one singlet exciton into two triplet excitons. Organic semiconductors, such as acenes and their soluble bis(triisopropylsilylethynyl) (TIPS) substituted counterparts, have played a major role in elucidating the understanding of the underlying mechanisms of singlet fission. Despite this, one prominent member of the acene family that has received little experimental attention to date is TIPS-anthracene, even with computational studies suggesting potential high singlet fission yields in the solid state. Here, time-resolved spectroscopic and magneto-photoluminescence measurements were performed on spin-cast films of TIPS-anthracene, showing evidence for singlet fission. A singlet fission yield of 19% (out of 200%) is estimated from transient absorption spectroscopy. Kinetic modeling of the magnetic field effect on photoluminescence suggests that fast rates of triplet dissociation lead to a low magnetic photoluminescence effect and that non-radiative decay of both the S1 and 1(TT) states is the cause for the low triplet yield.
Collapse
Affiliation(s)
- Damon M de Clercq
- School of Chemistry, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| | - Miles I Collins
- School of Physics, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| | - Nicholas P Sloane
- School of Physics, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| | - Jiale Feng
- School of Chemistry, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| | - Dane R McCamey
- School of Physics, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| | - Murad J Y Tayebjee
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney NSW 2052 Australia
| | - Michael P Nielsen
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney NSW 2052 Australia
| | - Timothy W Schmidt
- School of Chemistry, ARC Centre of Excellence in Exciton Science, UNSW Sydney NSW 2052 Australia
| |
Collapse
|
3
|
Pompetti N, Smyser KE, Feingold B, Owens R, Lama B, Sharma S, Damrauer NH, Johnson JC. Tetracene Diacid Aggregates for Directing Energy Flow toward Triplet Pairs. J Am Chem Soc 2024; 146. [PMID: 38606884 PMCID: PMC11046478 DOI: 10.1021/jacs.4c02058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/13/2024]
Abstract
A comprehensive investigation of the solution-phase photophysics of tetracene bis-carboxylic acid [5,12-tetracenepropiolic acid (Tc-DA)] and its related methyl ester [5,12-tetracenepropynoate (Tc-DE)], a non-hydrogen-bonding counterpart, reveals the role of the carboxylic acid moiety in driving molecular aggregation and concomitant excited-state behavior. Low-concentration solutions of Tc-DA exhibit similar properties to the popular 5,12-bis((triisopropylsilyl)ethynl)tetracene, but as the concentration increases, evidence for aggregates that form excimers and a new mixed-state species with charge-transfer (CT) and correlated triplet pair (TT) character is revealed by transient absorption and fluorescence experiments. Aggregates of Tc-DA evolve further with concentration toward an additional phase that is dominated by the mixed CT/TT state which is the only state present in Tc-DE aggregates and can be modulated with the solvent polarity. Computational modeling finds that cofacial arrangement of Tc-DA and Tc-DE subunits is the most stable aggregate structure and this agrees with results from 1H NMR spectroscopy. The calculated spectra of these cofacial dimers replicate the observed broadening in ground-state absorption as well as accurately predict the formation of a near-UV transition associated with a CT between molecular subunits that is unique to the specific aggregate structure. Taken together, the results suggest that the hydrogen bonding between Tc-DA molecules and the associated disruption of hydrogen bonding with solvent produce a regime of dimer-like behavior, absent in Tc-DE, that favors excimers rather than CT/TT mixed states. The control of aggregate size and structure using distinct functional groups, solute concentration, and solvent in tetracene promises new avenues for its use in light-harvesting schemes.
Collapse
Affiliation(s)
- Nicholas
F. Pompetti
- National
Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, United States
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Kori E. Smyser
- University
of Colorado, Boulder, Colorado 80401, United States
| | | | - Raythe Owens
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Bimala Lama
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Sandeep Sharma
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Niels H. Damrauer
- University
of Colorado, Boulder, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, University
of Colorado Boulder, Boulder, Colorado 80401, United States
| | - Justin C. Johnson
- National
Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, University
of Colorado Boulder, Boulder, Colorado 80401, United States
| |
Collapse
|
4
|
Wang Z, Xie X, Ma H. Simultaneous Intra- and Intermolecular Singlet Fission in Bipentacene Macrocycle Aggregates. J Phys Chem Lett 2024; 15:3523-3530. [PMID: 38522085 DOI: 10.1021/acs.jpclett.4c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Singlet fission (SF) is a process where a singlet state splits into two triplet states, which is essential for enhancing optoelectronic devices. Macrocyclic structures allow for precise control of chromophore orientation and facilitate singlet fission in solutions. However, the behavior of these structures in thin films, crucial for solid-state device optimization, remains underexplored. This study examines the aggregation and singlet fission processes of bipentacene macrocycles (BPc) in thin films using molecular dynamics simulations and electronic structure calculations. Findings indicate that BPc aggregates more rapidly with less chloroform, aligning parallel to the substrate. Intramolecular singlet fission (iSF) rates are rarely changed during evaporation, but the efficiency of intermolecular singlet fission (xSF) improves due to the increase in packing domains, suggesting that orderly crystal domains are not necessary for device efficiency. This opens avenues for varied device designs and traditional solution-based methods for optimal device development.
Collapse
Affiliation(s)
- Zhangxia Wang
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Xiaoyu Xie
- Qingdao Institute for Theoretical and Computational Sciences, School of Chemistry and Chemical Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Haibo Ma
- Qingdao Institute for Theoretical and Computational Sciences, School of Chemistry and Chemical Engineering, Shandong University, Qingdao, Shandong 266237, China
| |
Collapse
|
5
|
Gazdag T, Meiszter E, Mayer PJ, Holczbauer T, Ottosson H, Maurer AB, Abrahamsson M, London G. An Exploration of Substituent Effects on the Photophysical Properties of Monobenzopentalenes. Chemphyschem 2024; 25:e202300737. [PMID: 38284145 DOI: 10.1002/cphc.202300737] [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: 10/09/2023] [Revised: 12/18/2023] [Accepted: 01/26/2024] [Indexed: 01/30/2024]
Abstract
Monobenzopentalenes have received moderate attention compared to dibenzopentalenes, yet their accessibility as stable, non-symmetric structures with diverse substituents could be interesting for materials applications, including molecular photonics. Recently, monobenzopentalene was considered computationally as a potential chromophore for singlet fission (SF) photovoltaics. To advance this compound class towards photonics applications, the excited state energetics must be characterized, computationally and experimentally. In this report we synthesized a series of stable substituted monobenzopentalenes and provided the first experimental exploration of their photophysical properties. Structural and opto-electronic characterization revealed that all derivatives showed 1H NMR shifts in the olefinic region, bond length alternation in the pentalene unit, low-intensity absorptions reflecting the ground-state antiaromatic character and in turn the symmetry forbidden HOMO-to-LUMO transitions of ~2 eV and redox amphotericity. This was also supported by computed aromaticity indices (NICS, ACID, HOMA). Accordingly, substituents did not affect the fulfilment of the energetic criterion of SF, as the computed excited-state energy levels satisfied the required E(S1)/E(T1)>2 relationship. Further spectroscopic measurements revealed a concentration dependent quenching of the excited state and population of the S2 state on the nanosecond timescale, providing initial evidence for unusual photophysics and an alternative entry point for singlet fission with monobenzopentalenes.
Collapse
Affiliation(s)
- Tamás Gazdag
- MTA TTK Lendület Functional Organic Materials Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, 1117, Budapest, Magyar tudósok krt. 2, Hungary
- Hevesy György PhD School of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/a, Budapest, 1117, Hungary
| | - Enikő Meiszter
- MTA TTK Lendület Functional Organic Materials Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, 1117, Budapest, Magyar tudósok krt. 2, Hungary
- Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary
| | - Péter J Mayer
- MTA TTK Lendület Functional Organic Materials Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, 1117, Budapest, Magyar tudósok krt. 2, Hungary
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, Uppsala, 751 20, Sweden
| | - Tamás Holczbauer
- Chemical Crystallography Research Laboratory and Stereochemistry Research Group, Institute for Organic Chemistry, HUN-REN Research Centre for Natural Sciences, 1117, Budapest, Magyar tudósok krt. 2, Hungary
| | - Henrik Ottosson
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, Uppsala, 751 20, Sweden
| | - Andrew B Maurer
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 41296, Sweden
| | - Maria Abrahamsson
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 41296, Sweden
| | - Gábor London
- MTA TTK Lendület Functional Organic Materials Research Group, Institute of Organic Chemistry, HUN-REN Research Centre for Natural Sciences, 1117, Budapest, Magyar tudósok krt. 2, Hungary
| |
Collapse
|
6
|
Stuart AN, Kee TW, Huang DM. Role of Singlet and Triplet Excited States in the Oxygen-Mediated Photophysics and Photodegradation of Polyacenes. J Am Chem Soc 2024; 146:2174-2186. [PMID: 38197858 DOI: 10.1021/jacs.3c12245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Polyacenes, such as tetracene and pentacene, are common model systems for the study of photophysical phenomena such as singlet fission (SF) and triplet fusion, processes which may lead to increased photovoltaic efficiencies. While they exhibit desirable photophysical properties, these materials are not photostable and convert to unwanted endoperoxides in the presence of oxygen and light, limiting their use in real-world applications. Not only does oxygen degrade polyacenes but also it can affect their photophysics, leading to both the sensitization and quenching of different excited states. In this study, we characterize the effect of oxygen on 5,12-bis(triisopropylsilylethynyl) tetracene (TIPS-Tn) and 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-Pn) using transient absorption spectroscopy, and show that oxygen can significantly influence the population of excited states, in particular enhancing the polyacene triplet population. We additionally combine the time-resolved excited-state dynamics with photodegradation studies to determine the predominant mechanism of photooxidation, which has previously been unclear. We find that both molecules photodegrade predominantly via singlet oxygen; however, for TIPS-Tn, this occurs through the triplet state, whereas for TIPS-Pn, degradation occurs through the excited singlet. The photodegradation of TIPS-Tn is thus enhanced by faster rates of SF, whereas SF in TIPS-Pn increases the molecule's photostability. This work has implications both for the design of new materials for next-generation photovoltaics that can avoid photooxidation and for the study of their photophysics in real-world environments.
Collapse
Affiliation(s)
- Alexandra N Stuart
- 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
| | - David M Huang
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia
| |
Collapse
|
7
|
Bahng HW, Ertl CD, Yuan J, Wolf MO. Light-Controlled Switching of Perylene Bisimide Assemblies. J Phys Chem Lett 2023; 14:10369-10377. [PMID: 37948746 DOI: 10.1021/acs.jpclett.3c02468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Light-driven changes in supramolecular interactions in perylene bisimides (PBIs) with pendant sulfur-containing functional groups at the bay position are demonstrated. In the ground state, a noncovalent S···X interaction between the σ-hole on sulfur and a heteroatom, X (X = O, N, S), of a neighboring molecule is the main driving force for intermolecular interactions, while in the excited state it is the π-π interaction between PBI scaffolds which drives assembly. The presence of heteroatoms in the solvent results in acceleration of the π-stacking process via the formation of a PBI-solvent complex. The excited-state dynamics involved in the assembly process were revealed via time-resolved fluorescence and transient absorption spectroscopies, while steady-state spectroscopy was used to evaluate the structure of the supramolecular assembly.
Collapse
Affiliation(s)
- Hee-Won Bahng
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Cathrin D Ertl
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Jennifer Yuan
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Michael O Wolf
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| |
Collapse
|
8
|
Purdy M, Budden P, Fallon K, Gannett CN, Abruña HD, Zeng W, Friend R, Musser AJ, Bronstein H. Re-Thinking Dimer Design Principles with Indolonaphthyridine Intramolecular Singlet Fission. Chemistry 2023; 29:e202301547. [PMID: 37377132 DOI: 10.1002/chem.202301547] [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: 05/16/2023] [Revised: 06/27/2023] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Singlet fission is a phenomenon that could significantly improve the efficiency of photovoltaic devices. Indolonaphthyridine thiophene (INDT) is a photostable singlet fission material that could potentially be utilised in singlet fission-based photovoltaic devices. This study investigates the intramolecular singlet fission (i-SF) mechanism of INDT dimers linked via para-phenyl, meta-phenyl and fluorene bridging groups. Using ultra-fast spectroscopy the highest rate of singlet fission is found in the para-phenyl linked dimer. Quantum calculations show the para-phenyl linker encourages enhanced monomer electronic coupling. Increased rates of singlet fission were also observed in the higher polarity o-dichlorobenzene, relative to toluene, indicating that charge-transfer states have a role in mediating the process. The mechanistic picture of polarisable singlet fission materials, such as INDT, extends beyond the traditional mechanistic landscape.
Collapse
Affiliation(s)
- Michael Purdy
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Peter Budden
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Kealan Fallon
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Cara N Gannett
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Héctor D Abruña
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Weixuan Zeng
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Richard Friend
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Andrew J Musser
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| |
Collapse
|
9
|
Ringström R, Schroeder ZW, Mencaroni L, Chabera P, Tykwinski RR, Albinsson B. Triplet Formation in a 9,10-Bis(phenylethynyl)anthracene Dimer and Trimer Occurs by Charge Recombination Rather than Singlet Fission. J Phys Chem Lett 2023; 14:7897-7902. [PMID: 37642563 PMCID: PMC10494225 DOI: 10.1021/acs.jpclett.3c02050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023]
Abstract
We present an experimental study investigating the solvent-dependent dynamics of a 9,10-bis(phenylethynyl)anthracene monomer, dimer, and trimer. Using transient absorption spectroscopy, we have discovered that triplet excited state formation in the dimer and trimer molecules in polar solvents is a consequence of charge recombination subsequent to symmetry-breaking charge separation rather than singlet fission. Total internal reflection emission measurements of the monomer demonstrate that excimer formation serves as the primary decay pathway at a high concentration. In the case of highly concentrated solutions of the trimer, we observe evidence of triplet formation without the prior formation of a charge-separated state. We postulate that this is attributed to the formation of small aggregates, suggesting that oligomers mimicking the larger chromophore counts in crystals could potentially facilitate singlet fission. Our experimental study sheds light on the intricate dynamics of the 9,10-bis(phenylethynyl)anthracene system, elucidating the role of solvent- and concentration-dependent factors for triplet formation and charge separation.
Collapse
Affiliation(s)
- Rasmus Ringström
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Kemivägen 10, 412 96 Gothenburg, Sweden
| | - Zachary W. Schroeder
- Department
of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Letizia Mencaroni
- Department
of Chemistry Biology and Biotechnology, University of Perugia, via elce di sotto n. 8, 06123 Perugia, Italy
| | - Pavel Chabera
- The
Division of Chemical Physics and NanoLund, Lund University, 22100 Lund, Sweden
| | - Rik R. Tykwinski
- Department
of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Bo Albinsson
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Kemivägen 10, 412 96 Gothenburg, Sweden
| |
Collapse
|
10
|
Yoneda Y, Kuramochi H. Rapid-Scan Resonant Two-Dimensional Impulsive Stimulated Raman Spectroscopy of Excited States. J Phys Chem A 2023. [PMID: 37289973 DOI: 10.1021/acs.jpca.3c02489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Photochemical reactions occur in the electronically excited state, which is effectively represented by a multidimensional potential energy surface (PES) with a vast degree of freedom of nuclear coordinates. The elucidation of the intricate shape of the PES constitutes an important topic in the field of photochemistry and has long been studied both experimentally and theoretically. Recently, fully time-domain resonant two-dimensional Raman spectroscopy has emerged as a potentially powerful tool to provide unique information about the coupling between vibrational manifolds in the excited state. However, the wide application of this technique has been significantly hampered by the technical difficulties associated with experimental implementation and remains challenging. Herein, we demonstrate time-domain resonant two-dimensional impulsive stimulated Raman spectroscopy (2D-ISRS) of excited states using sub-10 fs pulses based on the rapid scan of the time delay, which facilitates the efficient collection of time-domain vibrational signals with high sensitivity. As a proof-of-principle experiment, we performed 2D-ISRS of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) in solution. Through 2D Fourier transformation of the high-quality time-time oscillatory signal, we obtained a 2D frequency-frequency correlation map of excited-state TIPS-pentacene in the broad frequency window of 0-2000 cm-1. The data clearly resolve a number of cross peaks that signify the correlations among excited-state vibrational manifolds. The high capability of the rapid-scan-based 2D-ISRS spectrometer presented in this study enables the systematic investigation of various photochemical reaction systems, thereby further promoting the understanding and applications of this new multidimensional spectroscopy.
Collapse
Affiliation(s)
- Yusuke Yoneda
- Research Center of Integrative Molecular Systems (CIMoS), Institute for Molecular Science, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585, Japan
| | - Hikaru Kuramochi
- Research Center of Integrative Molecular Systems (CIMoS), Institute for Molecular Science, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585, Japan
| |
Collapse
|
11
|
Jung S, Wang L, Sugiyama H, Uekusa H, Katayama T, Kamada K, Hamura T, Tamai N. Intramolecular Singlet Fission in Pentacene Oligomers via an Intermediate State. J Phys Chem B 2023; 127:4554-4561. [PMID: 37191388 DOI: 10.1021/acs.jpcb.3c00516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Intramolecular singlet fission (iSF) is an efficient strategy of multiexciton generation via a singlet exciton splitting into a correlated triplet pair in one organic molecule with more than two chromophores. Propeller-shaped iptycene-linked triisopropylsilyl(TIPS)-ethynyl functionalized pentacene oligomers (pent-monomer, pent-dimer, and pent-trimer) were synthesized, and the iSF dynamics of pent-dimer and -trimer were monitored by a visible-near-IR transient absorption (TA) spectroscopy. Quantum yields of the triplet pair, ∼80%, of both estimated by near-IR TA spectral analysis are in good agreement with the results of global analysis and triplet sensitization experiments. The iSF rate of pent-trimer is slightly faster than that of pent-dimer even with one more chromophore site. The unexpectedly weak difference indicates the existence of an intermediate process to realize iSF. The intermediate process might be determined by through-bond electronic coupling of the homoconjugation bridge in the pentacene oligomers. Our results suggest the importance of the rigid bridge to the fast iSF rate and the elongated lifetime of the correlated triplet pair in pentacene oligomers.
Collapse
Affiliation(s)
- Sunna Jung
- Department of Applied Chemistry for Environment, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Li Wang
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Haruki Sugiyama
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Megro-ku, 152-8551 Tokyo, Japan
| | - Hidehiro Uekusa
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Megro-ku, 152-8551 Tokyo, Japan
| | - Tetsuro Katayama
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Kenji Kamada
- IFMRI, National Institute of Advanced Industrial Science and Technology (AIST), 563-8577 Osaka, Japan
| | - Toshiyuki Hamura
- Department of Applied Chemistry for Environment, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Naoto Tamai
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| |
Collapse
|
12
|
Wang JX, Yin J, Gutiérrez-Arzaluz L, Thomas S, Shao W, Alshareef HN, Eddaoudi M, Bakr OM, Mohammed OF. Singlet Fission-Based High-Resolution X-Ray Imaging Scintillation Screens. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023:e2300406. [PMID: 37083237 DOI: 10.1002/advs.202300406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/02/2023] [Indexed: 05/03/2023]
Abstract
X-ray imaging technology is critical to numerous different walks of daily life, ranging from medical radiography and security screening all the way to high-energy physics. Although several organic chromophores are fabricated and tested as X-ray imaging scintillators, they generally show poor scintillation performance due to their weak X-ray absorption cross-section and inefficient exciton utilization efficiency. Here, a singlet fission-based high-performance organic X-ray imaging scintillator with near unity exciton utilization efficiency is presented. Interestingly, it is found that the X-ray sensitivity and imaging resolution of the singlet fission-based scintillator are dramatically improved by an efficient energy transfer from a thermally activated delayed fluorescence (TADF) sensitizer, in which both singlet and triplet excitons can be efficiently harnessed. The fabricated singlet fission-based scintillator exhibits a high X-ray imaging resolution of 27.5 line pairs per millimeter (lp mm-1 ), which exceeds that of most commercial scintillators, demonstrating its high potential use in medical radiography and security inspection.
Collapse
Affiliation(s)
- Jian-Xin Wang
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Jun Yin
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, 999077, P. R. China
| | - Luis Gutiérrez-Arzaluz
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Simil Thomas
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
- Materials Science and Engineering, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Wenyi Shao
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Husam N Alshareef
- Materials Science and Engineering, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mohamed Eddaoudi
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Osman M Bakr
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Omar F Mohammed
- Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| |
Collapse
|
13
|
Forecast R, Campaioli F, Schmidt TW, Cole JH. Photochemical Upconversion in Solution: The Role of Oxygen and Magnetic Field Response. J Phys Chem A 2023; 127:1794-1800. [PMID: 36753357 PMCID: PMC9969966 DOI: 10.1021/acs.jpca.2c08883] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/27/2023] [Indexed: 02/09/2023]
Abstract
Upconversion processes effectively convert two or more low energy photons into one higher energy photon, and they have diverse prospective applications in photovoltaics and biomedicine. We focus on two specific mechanisms for photochemical upconversion in solution: triplet-triplet annihilation (TTA) and singlet oxygen mediated energy transfer (SOMET). TTA is spin-selective, whereas SOMET is not, so the interplay between these two upconversion mechanisms can be examined via their different magnetic field responses. A kinetic model is developed and applied to explain the different photoluminescence profiles of oxygenated versus deoxygenated systems. From the magnetic field response, the triplet-triplet annihilation rate constant is estimated. The conditions required to maximize upconversion photoluminescence intensity in oxygenated solution are determined, providing a set of design principles to guide molecule choices for robust and air-stable upconversion systems in the future.
Collapse
Affiliation(s)
- Roslyn Forecast
- ARC
Centre of Excellence in Exciton Science and Chemical and Quantum Physics,
School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Francesco Campaioli
- ARC
Centre of Excellence in Exciton Science and Chemical and Quantum Physics,
School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Timothy W. Schmidt
- ARC
Centre of Excellence in Exciton Science, School of Chemistry, The University of NSW, Sydney, NSW 2052, Australia
| | - Jared H. Cole
- ARC
Centre of Excellence in Exciton Science and Chemical and Quantum Physics,
School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| |
Collapse
|
14
|
Nakamura S, Sakai H, Fuki M, Ooie R, Ishiwari F, Saeki A, Tkachenko NV, Kobori Y, Hasobe T. Thermodynamic Control of Intramolecular Singlet Fission and Exciton Transport in Linear Tetracene Oligomers. Angew Chem Int Ed Engl 2023; 62:e202217704. [PMID: 36578175 DOI: 10.1002/anie.202217704] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/26/2022] [Accepted: 12/28/2022] [Indexed: 12/30/2022]
Abstract
We newly synthesized a series of homo- and hetero-tetracene (Tc) oligomers to propose a molecular design strategy for the efficient exciton transport in linear oligomers by promoting correlated triplet pair (TT) dissociation and controlling sequential exciton trapping process of individual doubled triplet excitons (T+T) by intramolecular singlet fission. First, entropic gain effects on the number of Tc units are examined by comparing Tc-homo-oligomers [(Tc)n : n=2, 4, 6]. Then, a comparison of (Tc)n and Tc-hetero-oligomer [TcF3 -(Tc)4 -TcF3 ] reveals the vibronic coupling effect for entropic gain. Observed entropic effects on the T+T formation indicated that the exciton migration is rationalized by number of possible TT states increased both by increasing the number of Tc units and by the vibronic levels at the terminal TcF3 units. Finally, we successfully observed high-yield exciton trapping process (trapped triplet yield: ΦTrT =176 %).
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
| | - Rikuto Ooie
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Fumitaka Ishiwari
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Akinori Saeki
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - 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
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| |
Collapse
|
15
|
Millington O, Montanaro S, Leventis A, Sharma A, Dowland SA, Sawhney N, Fallon KJ, Zeng W, Congrave DG, Musser AJ, Rao A, Bronstein H. Soluble Diphenylhexatriene Dimers for Intramolecular Singlet Fission with High Triplet Energy. J Am Chem Soc 2023; 145:2499-2510. [PMID: 36683341 PMCID: PMC9896565 DOI: 10.1021/jacs.2c12060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Intramolecular singlet fission (iSF) facilitates single-molecule exciton multiplication, converting an excited singlet state to a pair of triplet states within a single molecule. A critical parameter in determining the feasibility of SF-enhanced photovoltaic designs is the triplet energy; many existing iSF materials have triplet energies too low for efficient transfer to silicon via a photon multiplier scheme. In this work, a series of six novel dimers based upon the high-triplet-energy, SF-active chromophore, 1,6-diphenyl-1,3,5-hexatriene (DPH) [E(T1) ∼ 1.5 eV], were designed, synthesized, and characterized. Transient absorption spectroscopy and fluorescence lifetime studies reveal that five of the dimers display iSF activity, with time constants for singlet fission varying between 7 ± 2 ps and 2.2 ± 0.2 ns and a high triplet yield of 163 ± 63% in the best-performing dimer. A strong dependence of the rate of fission on the coupling geometry is demonstrated. For optimized iSF behavior, close spatial proximity and minimal through-bond communication are found to be crucial for balancing the rate of SF against the reverse recombination process.
Collapse
Affiliation(s)
- Oliver Millington
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.,Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.
| | | | - Anastasia Leventis
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.
| | - Ashish Sharma
- Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.
| | - Simon A. Dowland
- Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.
| | - Nipun Sawhney
- Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.
| | - Kealan J. Fallon
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.,Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.
| | - Weixuan Zeng
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.
| | - Daniel G. Congrave
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.
| | - Andrew J. Musser
- Department
of Chemistry and Chemical Biology, Cornell
University, Baker Laboratory, Ithaca, New York14853, United States
| | - Akshay Rao
- Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.,
| | - Hugo Bronstein
- Department
of Chemistry, University of Cambridge, CambridgeCB2 1EW, U.K.,Cavendish
Laboratory, University of Cambridge, CambridgeCB3 0HE, U.K.,
| |
Collapse
|
16
|
Stuart AN, Tapping P, Kee T, Huang DM. Pitfalls of quantifying intersystem crossing rates in singlet-fission chromophore solutions. J Chem Phys 2022; 157:084312. [DOI: 10.1063/5.0100619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Singlet fission (SF), a process that produces two triplet excitons from one singlet exciton, has attracted recent interest for its potential to circumvent the detailed-balance efficiency limit of single-junction solar cells. For the potential of SF to be fully realized, accurate assignment and quantification of SF is necessary. Intersystem crossing (ISC) is another process of singlet to triplet conversion that is important to distinguish from SF to avoid either over- or under-estimation of SF triplet production. Here, we quantify an upper bound on the rate of ISC in two commonly studied SF chromophores, TIPS-pentacene and TIPS-tetracene, by using transient absorption spectroscopy of solutions of varying concentrations in toluene. We show that SF in solutions of these acenes has previously been misidentified as ISC, and vice versa. By determining a bimolecular SF rate constant in concentrated solutions in which SF dominates over ISC, we distinguish triplet formation due to SF from triplet formation due to ISC, and show that the characteristic time scale of ISC must be longer than 325 ns in TIPS-pentacene, while it must be longer than 118 ns in TIPS-tetracene. We additionally note that no excimer formation is observed in the relatively dilute (up to 8 mM) solutions studied here, indicating that previous excimer formation observed at much higher concentrations may be partially due to aggregate formation. This work highlights that an accurate quantification of ISC is crucial as it leads to accurate determination of SF rate constants and yields.
Collapse
Affiliation(s)
| | | | - Tak Kee
- Chemistry, The University of Adelaide Faculty of Sciences, Australia
| | | |
Collapse
|