1
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Gust D, Scholz M, Schumacher V, Mulatier JC, Pitrat D, Guy L, Oum K, Lenzer T. Annealing temperature-dependent induced supramolecular chiroptical response of copolymer thin films studied by pump-modulated transient circular dichroism spectroscopy. Sci Rep 2024; 14:12694. [PMID: 38830981 PMCID: PMC11148131 DOI: 10.1038/s41598-024-63126-4] [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: 02/23/2024] [Accepted: 05/22/2024] [Indexed: 06/05/2024] Open
Abstract
Copolymer thin films showing induced supramolecular chirality are of considerable interest for optoelectronic applications such as organic light-emitting diodes. Here, we introduce a new helicene-like chiral additive with two octyloxy substituents which displays excellent chiral induction properties in an achiral polyfluorene copolymer, leading to a circular dichroism (CD) response of up to 10,000 mdeg. This chiral inducer also displays very good thermal stability, which enables us to perform an extended study on the induced chiroptical properties of the cholesteric copolymer thin films annealed at different temperatures in the range 140-260 °C. Starting from about 180 °C, a distinct change in the morphology of the CD-active film is observed by CD microscopy, from micrometre-size granular to extended CD-active regions, where the latter ones display skewed distributions of the dissymmetry parameter gabs. Broadband Müller matrix spectroscopy finds a pronounced CD and circular birefringence (CB) response and only weak linear dichroism (LD, LD') and linear birefringence (LB, LB'). Ultrafast transient CD spectroscopy with randomly polarised excitation reveals a clean mirror-image-type transient response, which shows a second-order decay of the S1 population due to singlet-singlet annihilation processes.
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Affiliation(s)
- Domenic Gust
- Faculty IV: School of Science and Technology, Department Chemistry and Biology, Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany
| | - Mirko Scholz
- Faculty IV: School of Science and Technology, Department Chemistry and Biology, Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany
| | - Vivien Schumacher
- Faculty IV: School of Science and Technology, Department Chemistry and Biology, Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany
| | - Jean-Christophe Mulatier
- Univ. Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Université Claude Bernard Lyon 1, 69342, Lyon, France
| | - Delphine Pitrat
- Univ. Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Université Claude Bernard Lyon 1, 69342, Lyon, France
| | - Laure Guy
- Univ. Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Université Claude Bernard Lyon 1, 69342, Lyon, France
| | - Kawon Oum
- Faculty IV: School of Science and Technology, Department Chemistry and Biology, Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany.
| | - Thomas Lenzer
- Faculty IV: School of Science and Technology, Department Chemistry and Biology, Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany.
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2
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Joseph JP, Malone T, Abraham SR, Dutta A, Gupta S, Kuzmin A, Baev A, Swihart MT, Hendrickson JR, Prasad PN. Plasticizer-Induced Enhancement of Mesoscale Dissymmetry in Thin Films of Chiral Polymers with Variable Chain Length. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2305684. [PMID: 37725635 DOI: 10.1002/adma.202305684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/13/2023] [Indexed: 09/21/2023]
Abstract
Conjugated polymers with chiral side chains are of interest in areas including chiral photonics, optoelectronics, and chemical and biological sensing. However, the low dissymmetry factors of most neat polymer thin films have limited their practical application. Here, a robust method to increase the absorption dissymmetry factor in a poly-fluorene-thiophene (PF8TS series) system is demonstrated by varying molecular weight and introducing an achiral plasticizer, polyethylene mono alcohol (PEM-OH). Extending chain length within the optimal range and adding this long-chain alcohol significantly enhance the chiroptical properties of spin-coated and annealed thin films. Mueller matrix spectroscopic ellipsometry (MMSE) analysis shows good agreement with the steady-state transmission measurements confirming a strong chiral response (circular dichroism (CD) and circular birefringence (CB)), ruling out linear dichroism, birefringence, and specific reflection effects. Solid-state NMR studies of annealed hybrid chiral polymer systems show enhancement of signals associated with aromatic π-stacked backbone and the ordered side-chain conformations. Further studies using Raman spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), atomic force microscopy (AFM), and polarized optical microscopy (POM) indicate that PEM-OH facilitates mesoscopic crystal domain ordering upon annealing. This provides new insights into routes for tuning optical activity in conjugated polymers.
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Affiliation(s)
- Jojo P Joseph
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Trent Malone
- Department of Electro-Optics and Photonics, University of Dayton, Dayton, OH, 45469, USA
- Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Dayton, OH, 45433, USA
| | - Shema R Abraham
- Department of Chemical and Biological Engineering, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Avisek Dutta
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Sonal Gupta
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Andrey Kuzmin
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Alexander Baev
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Mark T Swihart
- Department of Chemical and Biological Engineering, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
| | - Joshua R Hendrickson
- Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Dayton, OH, 45433, USA
| | - Paras N Prasad
- Department of Chemistry and The Institute for Lasers, Photonics, and Biophotonics, University at Buffalo, SUNY, Buffalo, NY, 14260, USA
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3
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Minion L, Wade J, Moreno‐Naranjo JM, Ryan S, Siligardi G, Fuchter MJ. Insights into the origins of inverted circular dichroism in thin films of a chiral side chain polyfluorene. Chirality 2023; 35:817-825. [PMID: 37349263 PMCID: PMC10946986 DOI: 10.1002/chir.23601] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/16/2023] [Accepted: 06/05/2023] [Indexed: 06/24/2023]
Abstract
We synthesized a fluorene-bithiophene co-polymer with chiral side chains (cPFT2) and investigated its chiroptical properties via synchotronradiation circular dichroism. We observed that thin films of the polymer display an intense circular dichroism (CD) upon annealing, which is of opposite handedness to the CD reported for similar polyfluorenes bearing the same enantiomeric chiral side chain. We then contrast the properties of this polymer with chiral side chain fluorene homopolymer (cPF) and observe large differences in their thin film morphology. Using photoluminescence spectroscopy, we uncover evidence of polymer chain bending in cPFT2, which is further supported by theoretical calculations, and propose an explanation for the observed inverted optical activity.
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Affiliation(s)
- Louis Minion
- Department of MaterialsImperial College LondonLondonUK
- Centre for Processable ElectronicsImperial College London, South Kensington CampusLondonUK
- B23 Beamline, Diamond Light Source Ltd, Harwell Science and Innovation CampusDidcotUK
| | - Jessica Wade
- Department of MaterialsImperial College LondonLondonUK
- Centre for Processable ElectronicsImperial College London, South Kensington CampusLondonUK
| | - Juan Manuel Moreno‐Naranjo
- Centre for Processable ElectronicsImperial College London, South Kensington CampusLondonUK
- Department of Chemistry and Molecular Sciences Research HubImperial College London, White City CampusLondonUK
| | - Seán Ryan
- Department of Chemistry and Molecular Sciences Research HubImperial College London, White City CampusLondonUK
| | - Giuliano Siligardi
- B23 Beamline, Diamond Light Source Ltd, Harwell Science and Innovation CampusDidcotUK
| | - Matthew J. Fuchter
- Centre for Processable ElectronicsImperial College London, South Kensington CampusLondonUK
- Department of Chemistry and Molecular Sciences Research HubImperial College London, White City CampusLondonUK
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4
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Morgenroth M, Scholz M, Guy L, Oum K, Lenzer T. Spatiotemporal Mapping of Efficient Chiral Induction by Helicene-Type Additives in Copolymer Thin Films. Angew Chem Int Ed Engl 2022; 61:e202203075. [PMID: 35577763 PMCID: PMC9401025 DOI: 10.1002/anie.202203075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Indexed: 11/21/2022]
Abstract
We observed efficient induction of chirality in polyfluorene copolymer thin films by mixing with helicene-type chiral additives based on the dibenzo[c,h]acridine motif. Images obtained from circular dichroism (CD) and circularly polarized luminescence (CPL) microscopy provide information about the chiral arrangements in the thin films with diffraction-limited resolution. The CD signal shows a characteristic dependence on the film thickness, which supports a supramolecular origin of the strong chiral response of the copolymer. In particular, we demonstrate the discrimination between films of opposite chirality based on their ultrafast transient chiral response through the use of femtosecond broadband CD spectroscopy and a newly developed setup for transient CPL spectroscopy with 28 ps time resolution. A systematic variation of the enantiomeric excess of the chiral additive shows that the "Sergeants and Soldiers" concept and "Majority Rules" are not obeyed.
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Affiliation(s)
- Marius Morgenroth
- University of SiegenFaculty IV: School of Science and TechnologyDepartment Chemistry and BiologyPhysical Chemistry 2Adolf-Reichwein-Str. 257076SiegenGermany
| | - Mirko Scholz
- University of SiegenFaculty IV: School of Science and TechnologyDepartment Chemistry and BiologyPhysical Chemistry 2Adolf-Reichwein-Str. 257076SiegenGermany
| | - Laure Guy
- Univ. LyonENS de LyonCNRS UMR 5182Université Claude Bernard Lyon 1, Laboratoire de Chimie69342LyonFrance
| | - Kawon Oum
- University of SiegenFaculty IV: School of Science and TechnologyDepartment Chemistry and BiologyPhysical Chemistry 2Adolf-Reichwein-Str. 257076SiegenGermany
| | - Thomas Lenzer
- University of SiegenFaculty IV: School of Science and TechnologyDepartment Chemistry and BiologyPhysical Chemistry 2Adolf-Reichwein-Str. 257076SiegenGermany
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5
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Morgenroth M, Scholz M, Guy L, Oum K, Lenzer T. Räumliche und zeitliche Kartierung effizienter chiraler Induktion durch helikale Additive in dünnen Copolymerfilmen. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Marius Morgenroth
- Universität Siegen Fakultät IV: Naturwissenschaftlich-Technische Fakultät Department Chemie und Biologie, Physikalische Chemie 2 Adolf-Reichwein-Str. 2 57076 Siegen Deutschland
| | - Mirko Scholz
- Universität Siegen Fakultät IV: Naturwissenschaftlich-Technische Fakultät Department Chemie und Biologie, Physikalische Chemie 2 Adolf-Reichwein-Str. 2 57076 Siegen Deutschland
| | - Laure Guy
- Univ. Lyon ENS de Lyon CNRS UMR 5182 Université Claude Bernard Lyon 1, Laboratoire de Chimie 69342 Lyon Frankreich
| | - Kawon Oum
- Universität Siegen Fakultät IV: Naturwissenschaftlich-Technische Fakultät Department Chemie und Biologie, Physikalische Chemie 2 Adolf-Reichwein-Str. 2 57076 Siegen Deutschland
| | - Thomas Lenzer
- Universität Siegen Fakultät IV: Naturwissenschaftlich-Technische Fakultät Department Chemie und Biologie, Physikalische Chemie 2 Adolf-Reichwein-Str. 2 57076 Siegen Deutschland
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6
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Morgenroth M, Scholz M, Cho MJ, Choi DH, Oum K, Lenzer T. Mapping the broadband circular dichroism of copolymer films with supramolecular chirality in time and space. Nat Commun 2022; 13:210. [PMID: 35017508 PMCID: PMC8752614 DOI: 10.1038/s41467-021-27886-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 12/17/2021] [Indexed: 01/30/2023] Open
Abstract
Measurements of the electronic circular dichroism (CD) are highly sensitive to the absolute configuration and conformation of chiral molecules and supramolecular assemblies and have therefore found widespread application in the chemical and biological sciences. Here, we demonstrate an approach to simultaneously follow changes in the CD and absorption response of photoexcited systems over the ultraviolet-visible spectral range with 100 fs time resolution. We apply the concept to chiral polyfluorene copolymer thin films and track their electronic relaxation in detail. The transient CD signal stems from the supramolecular response of the system and provides information regarding the recovery of the electronic ground state. This allows for a quantification of singlet-singlet annihilation and charge-pair formation processes. Spatial mapping of chiral domains on femtosecond time scales with a resolution of 50 μm and diffraction-limited steady-state imaging of the circular dichroism and the circularly polarised luminescence (CPL) of the films is demonstrated.
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Affiliation(s)
- Marius Morgenroth
- Department Chemistry and Biology, Physical Chemistry 2, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany
| | - Mirko Scholz
- Department Chemistry and Biology, Physical Chemistry 2, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany
| | - Min Ju Cho
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Dong Hoon Choi
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Kawon Oum
- Department Chemistry and Biology, Physical Chemistry 2, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany.
| | - Thomas Lenzer
- Department Chemistry and Biology, Physical Chemistry 2, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57068, Siegen, Germany.
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7
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Albano G, Pescitelli G, Di Bari L. Chiroptical Properties in Thin Films of π-Conjugated Systems. Chem Rev 2020; 120:10145-10243. [PMID: 32892619 DOI: 10.1021/acs.chemrev.0c00195] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chiral π-conjugated molecules provide new materials with outstanding features for current and perspective applications, especially in the field of optoelectronic devices. In thin films, processes such as charge conduction, light absorption, and emission are governed not only by the structure of the individual molecules but also by their supramolecular structures and intermolecular interactions to a large extent. Electronic circular dichroism, ECD, and its emission counterpart, circularly polarized luminescence, CPL, provide tools for studying aggregated states and the key properties to be sought for designing innovative devices. In this review, we shall present a comprehensive coverage of chiroptical properties measured on thin films of organic π-conjugated molecules. In the first part, we shall discuss some general concepts of ECD, CPL, and other chiroptical spectroscopies, with a focus on their applications to thin film samples. In the following, we will overview the existing literature on chiral π-conjugated systems whose thin films have been characterized by ECD and/or CPL, as well other chiroptical spectroscopies. Special emphasis will be put on systems with large dissymmetry factors (gabs and glum) and on the application of ECD and CPL to derive structural information on aggregated states.
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Affiliation(s)
- Gianluigi Albano
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Di Bari
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Giuseppe Moruzzi 13, 56124 Pisa, Italy
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8
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Scholz M, Morgenroth M, Cho MJ, Choi DH, Lenzer T, Oum K. Coherent acoustic phonon dynamics in chiral copolymers. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2019; 6:064502. [PMID: 31893213 PMCID: PMC6927817 DOI: 10.1063/1.5124438] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
Coherent phonon oscillations in the UV-Vis transient absorption and circular dichroism response of two chiral polyfluorene-based copolymer thin films are investigated. A slow oscillation in the hundred picosecond regime indicates the propagation of a longitudinal acoustic phonon with a frequency in the gigahertz range through cholesteric films of PFPh and PFBT, which allow for the optical determination of the longitudinal sound velocity in these polymers, with values of (2550 ± 140) and (2490 ± 150) m s-1, respectively. The oscillation is induced by a strain wave, resulting in a pressure-induced periodic shift of the electronic absorption bands, as extracted from a Fourier analysis of the transient spectra. The acoustic phonon oscillation is also clearly detected in the transient circular dichroism (TrCD) response of PFPh, indicating a transient pressure-induced shift of the CD spectrum and possibly also phonon-induced chirality changes via pitch length modulation of the cholesteric helical polymer stack.
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Affiliation(s)
- Mirko Scholz
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Marius Morgenroth
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Min Ju Cho
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 5 Anam-dong, Sungbuk-gu, Seoul 136-701, South Korea
| | - Dong Hoon Choi
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 5 Anam-dong, Sungbuk-gu, Seoul 136-701, South Korea
| | - Thomas Lenzer
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Kawon Oum
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
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9
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Scholz M, Morgenroth M, Cho MJ, Choi DH, Oum K, Lenzer T. Ultrafast Broadband Transient Absorption and Circular Dichroism Reveal Relaxation of a Chiral Copolymer. J Phys Chem Lett 2019; 10:5160-5166. [PMID: 31436421 DOI: 10.1021/acs.jpclett.9b02061] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We present a study of the photoinduced dynamics of the chiral polyfluorene-phenylene copolymer PFPh in THF and in cholesteric thin films. After photoexcitation at 370 nm in THF, ultraviolet-visible-near-infrared (UV-vis-NIR) transient absorption spectra show fast subpicosecond to picosecond intrachain migration of singlet excitons, solvation dynamics, and an exciton lifetime of 410 ps. The PFPh thin film features also interchain singlet exciton migration and exhibits shorter (2.1 and 240 ps) and longer lifetime components (2800 ps, interchain recombination). Furthermore, a setup for ultrafast UV-vis broadband transient circular dichroism (TrCD) spectroscopy has been developed. Fast supramolecular relaxation processes are observed, which are linked to changes in the anisotropic polarizability and pitch length of the cholesteric film. Such combined ultrafast transient CD and absorption experiments hold promise to reveal not only details of relaxation processes in supramolecular arrangements but also structural rearrangements of chiral molecular systems featuring CD signals in the UV-vis region.
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Affiliation(s)
- Mirko Scholz
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Marius Morgenroth
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Min Ju Cho
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 5 Anam-dong, Sungbuk-gu, Seoul 136-701, Korea
| | - Dong Hoon Choi
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, 5 Anam-dong, Sungbuk-gu, Seoul 136-701, Korea
| | - Kawon Oum
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
| | - Thomas Lenzer
- Physical Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany
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10
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Kulkarni C, Meskers SCJ, Palmans ARA, Meijer EW. Amplifying Chiroptical Properties of Conjugated Polymer Thin-Film Using an Achiral Additive. Macromolecules 2018; 51:5883-5890. [PMID: 30135611 PMCID: PMC6096448 DOI: 10.1021/acs.macromol.8b01077] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/16/2018] [Indexed: 01/05/2023]
Abstract
Chiral conjugated polymers bearing enantiopure side chains offer the possibility to harness the effect of chirality in organic electronic devices. However, its use is hampered by the low degree of circular polarization in absorption (gabs) in most of the conjugated polymer thin-films studied. Here we demonstrate a versatile method to significantly increase the gabs by using a few weight percentages of a commercially available achiral long-chain alcohol as an additive. This additive enhances the chiroptical properties in both absorption and emission by ca. 5-10 times in the thin-films. We envisage that the alcohol additive acts as a plasticizer which enhances the long-range chiral liquid crystalline ordering of the polymer chains, thereby amplifying the chiroptical properties in the thin-film. The application of this methodology to various conjugated polymers has been demonstrated.
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Affiliation(s)
- Chidambar Kulkarni
- Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600 MB, The Netherlands
| | - Stefan C J Meskers
- Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600 MB, The Netherlands
| | - Anja R A Palmans
- Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600 MB, The Netherlands
| | - E W Meijer
- Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600 MB, The Netherlands
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11
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Ma J, Wang Y, Li X, Yang L, Quan Y, Cheng Y. Aggregation-induced CPL response from chiral binaphthyl-based AIE-active polymers via supramolecular self-assembled helical nanowires. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.04.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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12
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Kulkarni C, Di Nuzzo D, Meijer EW, Meskers SCJ. Pitch and Handedness of the Cholesteric Order in Films of a Chiral Alternating Fluorene Copolymer. J Phys Chem B 2017; 121:11520-11527. [PMID: 29200297 PMCID: PMC6150679 DOI: 10.1021/acs.jpcb.7b10236] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
![]()
The
molecular organization in thermally annealed films of poly(9,9-bis((S)-3,7-dimethyloctyl)-2,7-fluorene-alt-benzothiadiazole)
is investigated using polarized light. Measurement of linear polarization
in transmission and reflection as a function of layer thickness and
orientation directly show a left handed cholesteric organization with
a pitch length of 600 nm. Results are corroborated by measurements
of circularly polarized reflection and generalized ellipsometry and
are compared to calculations of the optical properties based on the
Maugin–Oseen–DeVries model. For wavelengths near the
lowest allowed optical transition, light with the same handedness
as the cholesteric arrangement (left) is found to be reflected and
transmitted with a probability higher than right circularly polarized
light. The high transmission for left polarized light is interpreted
as an optical manifestation of the Borrmann effect.
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Affiliation(s)
- Chidambar Kulkarni
- Department of Chemical Engineering and Chemistry and Institute of Complex Molecular Systems, Eindhoven University of Technology , 5612 AZ Eindhoven, The Netherlands
| | - Daniele Di Nuzzo
- Department of Physics, University of Cambridge , Cambridge CB2 1 TN, United Kingdom
| | - E W Meijer
- Department of Chemical Engineering and Chemistry and Institute of Complex Molecular Systems, Eindhoven University of Technology , 5612 AZ Eindhoven, The Netherlands
| | - Stefan C J Meskers
- Department of Chemical Engineering and Chemistry and Institute of Complex Molecular Systems, Eindhoven University of Technology , 5612 AZ Eindhoven, The Netherlands
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13
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Pang X, Tan X, Wang J, Liu L, You Q, Sun Q, Wang Y, Tan F, Li N. Hollow Au-Cu Nanocomposite for Real-Time Tracing Photothermal/Antiangiogenic Therapy. Adv Healthc Mater 2017; 6. [PMID: 28464525 DOI: 10.1002/adhm.201700099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/01/2017] [Indexed: 11/08/2022]
Abstract
High absorption in the near-infrared (NIR) region is essential for a photoabsorbing agents to realize efficient photothermal therapy (PTT) for cancer. Here, a novel hollow Au-Cu nanocomposite (HGCNs) is developed, which displays a significantly enhanced NIR surface plasmon resonance absorption and photothermal transduction efficiency. Besides, fluorescent polymer dots poly(9,9-dioctylfluorene-2,7-diyl-co-benzothiadiazole) (PFBT) and chemotherapeutic mammalian target of rapamycin (mTOR) inhibitor agent rapamycin (RAPA) are attached onto the HGCNs (RAPA/PFBT-HGCNs) for real-time NIR fluorescence tracing and combined PTT/antiangiogenesis therapy. In particular, due to the fluorescence resonance energy transfer effect, RAPA/PFBT-HGCNs can act as NIR-activatable on/off probe system for real-time tracing of tumor tissues. A standard in vitro cellular uptake study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, dual-staining study, and flow cytometry assay reveal that the RAPA/PFBT-HGCNs combined with NIR laser exhibit higher drug accumulation and cytotoxicity in both tumor cells and epithelial cells. Moreover, the margins of tumor and normal tissue can be accurately indicated by NIR-stimulated dequenched PFBT after 24 h intravenous administration. Further, tumor growth can be considerably hampered by the optimal formulation plus laser treatment with relatively lower side effects. Consequently, the work highlights the real-time tracing and enhanced PTT/antiangiogenesis therapy prospects of the established HGCNs with tremendous potential for treatment of cancer.
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Affiliation(s)
- Xiaojuan Pang
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Xiaoxiao Tan
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Jinping Wang
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Li Liu
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Qing You
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Qi Sun
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Yidan Wang
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Fengping Tan
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
| | - Nan Li
- Tianjin Key Laboratory of Drug Delivery & High-Efficiency; School of Pharmaceutical Science and Technology; Tianjin University; Tianjin 300072 P. R. China
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