101
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Levine M, Song I, Andrew TL, Kooi SE, Swager TM. Photoluminescent energy transfer from poly(phenyleneethynylene)s to near-infrared emitting fluorophores. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pola.24123] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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102
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Meng K, Ding Q, Wang S, He Y, Li Y, Gong Q. Spatial conformation and charge recombination properties of polythiophene derivatives with thienylene-vinylene side chains investigated by static and femtosecond spectroscopy. J Phys Chem B 2010; 114:2602-6. [PMID: 20141109 DOI: 10.1021/jp909271e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report herein the photophysics of three two-dimensional polythiophene derivatives, with different lengths of thienylene-vinylene conjugated side chains, in comparison with regioregular poly(3-hexylthiophene) (P3HT). In solution, an evolution from stimulated emission to photoinduced absorption (PIA) at emission peak is discovered with increasing length of side chains, indicating larger steric hindrance by longer side chains. The exciton lifetime is reduced by a factor of five when the thienylene-vinylene side chain is prolonged to three units. In the film form, we investigate the dynamics of the two PIA bands, assigned to intrachain exciton and interchain polaron pairs, respectively. The analysis of the dynamics suggests that their intrachain exciton decays are similar to the one-dimensional P3HT. The recombination possibility of delocalized interchain polaron pairs occurring in 0.9 ps is reduced with longer thienylene-vinylene side chain samples. Compared with regioregular P3HT film, which self-organizes to form lamellae crystal morphology, the morphologies of these three two-dimensional polythiophenes are amorphous, attributed to the large steric hindrance caused by the existence of side chains. This design of polythiophene derivatives provides the reduction of recombination possibility for delocalized interchain polaron pairs generated in the polymer.
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Affiliation(s)
- Kang Meng
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing, China, 100871
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103
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Affiliation(s)
- Tracey M Clarke
- Centre for Plastic Electronics, Department of Chemistry, Imperial College London, London, SW7 2AZ, United Kingdom
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104
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Köse ME, Graf P, Kopidakis N, Shaheen SE, Kim K, Rumbles G. Exciton Migration in Conjugated Dendrimers: A Joint Experimental and Theoretical Study. Chemphyschem 2009; 10:3285-94. [DOI: 10.1002/cphc.200900386] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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105
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Yang JS, Yan JL, Lin CK, Chen CY, Xie ZY, Chen CH. Pentiptycene-Derived Oligo(p-phenyleneethynylene)s: Conformational Control, Chain-Length Effects, Localization of Excitation, and Intrachain Resonance Energy Transfer. Angew Chem Int Ed Engl 2009; 48:9936-9. [DOI: 10.1002/anie.200905405] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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106
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Lin H, Tian Y, Zapadka K, Persson G, Thomsson D, Mirzov O, Larsson PO, Widengren J, Scheblykin IG. Fate of excitations in conjugated polymers: single-molecule spectroscopy reveals nonemissive "dark" regions in MEH-PPV individual chains. NANO LETTERS 2009; 9:4456-4461. [PMID: 19860455 DOI: 10.1021/nl9027473] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Single chains of the conjugated polymer MEH-PPV (poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene)) were studied with wide-field fluorescence microscopy (dispersion in inert polymer matrices) and with fluorescence correlation spectroscopy (chloroform solution). The fluorescence yield of individual molecules in matrices was found to be 1-2 orders of magnitude lower than that in solution and it decreased substantially with increasing chain length. It suggests that isolation of MEH-PPV molecules in polymer matrices creates favorable conditions for photogeneration of nonemissive primary excited states.
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Affiliation(s)
- Hongzhen Lin
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
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107
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Yang JS, Yan JL, Lin CK, Chen CY, Xie ZY, Chen CH. Pentiptycene-Derived Oligo(p-phenyleneethynylene)s: Conformational Control, Chain-Length Effects, Localization of Excitation, and Intrachain Resonance Energy Transfer. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200905405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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108
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Osad'ko IS. Super-Poissonian statistics of on-off jumps in blinking fluorescence of single molecules. J Chem Phys 2009; 131:185101. [PMID: 19916627 DOI: 10.1063/1.3258272] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Blinking fluorescence of a single guest molecule embedded in a polymer matrix and excited by cw laser light is considered. Such fluorescence exhibits quantum jumps from bright on-intervals to dark off-intervals, i.e., so-called on-->off jumps. A system with one type of on-intervals and with two types of off-intervals is studied. A distribution function w(N)(T) for the number N of on-->off jumps in a time interval T is derived. The distribution function is expressed via a threefold integral of three Poissonian functions, each of which relates to the corresponding exponential process in the quantum dynamics of a fluorescent impurity center. Numerical calculations of the distribution function w(N)(T) for four time intervals T of various durations are carried out. The distribution function w(N)(T) is broader as compared with the Poissonian one and has two maxima, one of which relates to observed time intervals without on-->off jumps.
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Affiliation(s)
- I S Osad'ko
- Lebedev Physical Institute, RAS, Moscow 119991, Russia.
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109
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Guo J, Ohkita H, Benten H, Ito S. Near-IR Femtosecond Transient Absorption Spectroscopy of Ultrafast Polaron and Triplet Exciton Formation in Polythiophene Films with Different Regioregularities. J Am Chem Soc 2009; 131:16869-80. [DOI: 10.1021/ja906621a] [Citation(s) in RCA: 342] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jiamo Guo
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan
| | - Hideo Ohkita
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan
| | - Hiroaki Benten
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan
| | - Shinzaburo Ito
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan
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110
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Dias FB, Kamtekar KT, Cazati T, Williams G, Bryce MR, Monkman AP. Exciton Diffusion in Polyfluorene Copolymer Thin Films: Kinetics, Energy Disorder and Thermally Assisted Hopping. Chemphyschem 2009; 10:2096-104. [DOI: 10.1002/cphc.200900112] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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111
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Mirzov O, Bloem R, Hania PR, Thomsson D, Lin H, Scheblykin IG. Polarization portraits of single multichromophoric systems: visualizing conformation and energy transfer. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:1877-1888. [PMID: 19384881 DOI: 10.1002/smll.200801168] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A novel technique, two-dimensional (2D) polarization single-molecule imaging, is presented. It is based on measurements and analysis of fluorescence intensity as a function of excitation and emission polarization angles. The technique allows recording of full information on the steady-state polarization properties of fluorescent objects. It is particularly suitable for application to single multichromophoric systems (molecules or nanoparticles) with energy transfer (ET) between different chromophores (e.g., single fluorescent pi-conjugated polymer chains). The 2D polarization data simultaneously provide information on the conformation of the system and the efficiency of its internal excitation ET. The technique is used to characterize single chains and different kinds of chain aggregates of different conjugated polymers at different temperatures. The 2D polarization measurements reveal a dramatic difference in ET taking place in these systems. Clear temperature dependence of ET is observed for individual aggregates as well as for their statistical ensembles. Also, a dependence on solvent and aggregate size is shown. Additionally, extensive "traditional one-dimensional" polarization results on the polarization anisotropy of fluorescence excitation and emission are presented. These results and findings are discussed in relation to internal organization of the nano-objects under study.
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Affiliation(s)
- Oleg Mirzov
- Chemical Physics, Lund University, P.O. Box 124, 22100 Lund, Sweden
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112
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Siebert R, Akimov D, Schmitt M, Winter A, Schubert US, Dietzek B, Popp J. Spectroscopic investigation of the ultrafast photoinduced dynamics in pi-conjugated terpyridines. Chemphyschem 2009; 10:910-9. [PMID: 19301307 DOI: 10.1002/cphc.200800847] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ultrafast light-induced processes in a series of pi-conjugated mono-, bis-, tris- and tetrakis(terpyridine) derivatives are investigated by femtosecond time-resolved spectroscopy. Non-exponential excited-state dynamics involving singlet-triplet intersystem crossing are observed which span from picoseconds to nanoseconds (see figure). Time-resolved spectroscopy is applied to investigate the ultrafast relaxation dynamics of several pi-conjugated mono-, bis-, tris- and tetrakis(terpyridine) derivatives. This particular series of structurally closely related systems was prepared applying efficient synthetic strategies and resembles key building blocks for a wide range of photoactive complexes, dendrimers and metallo-polymers with resulting potential applications, for example, in photovoltaics or as organic light-emitting diodes. Aiming for applications of supramolecular assemblies based on these recently presented terpyridine ligands a detailed knowledge of the light-induced processes of the ligands themselves represents a prerequisite. By applying femtosecond time-resolved absorption spectroscopy in concert with time-resolved fluorescence and Raman measurements, we detail the photophysical properties.
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Affiliation(s)
- Ronald Siebert
- Institute for Physical Chemistry, Friedrich-Schiller-University Jena, Helmholtzweg 4, 07743 Jena, Germany
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113
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Huang J, Wu Y, Fu H, Zhan X, Yao J, Barlow S, Marder SR. Photoinduced Intramolecular Electron Transfer in Conjugated Perylene Bisimide-Dithienothiophene Systems: A Comparative Study of a Small Molecule and a Polymer. J Phys Chem A 2009; 113:5039-46. [DOI: 10.1021/jp8107655] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Jie Huang
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Yishi Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Hongbing Fu
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Xiaowei Zhan
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Jiannian Yao
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Stephen Barlow
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Seth R. Marder
- Beijing National Laboratory for Molecular Sciences (BNLMS) and Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China, and School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332
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114
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Osad'ko IS, Fedyanin VV. Manifestation of single macromolecule quantum dynamics in photon distribution function of blinking fluorescence. J Chem Phys 2009; 130:064904. [PMID: 19222295 DOI: 10.1063/1.3055287] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Distribution function w(N)(T) for photons created by three-level nanoparticle in time interval T under cw laser excitation is calculated for various methods of photon counting. It is found that each exponential process exp(-lambda(i)t) in quantum dynamics of three-level nanoparticle manifests itself via Poissonian function P(N)(lambda(i)t)=(lambda(i)t)(N) exp(-lambda(i)t)/N! in the photon distribution function w(N)(T). The distribution function w(N)(T) is expressed via two or three integrals of two or three Poissonian functions P(N)(lambda(i)t). The simple mathematical expression for w(N)(T) enables one to calculate photon distribution in blinking fluorescence with on and off intervals. A scaling between photon distribution function w(N)(T) and photoelectric pulse distribution function w(n)(T) is found. Comparison of the theoretical distribution w(n)(T) and the distribution measured in blinking fluorescence of single polymer molecule dPPV-PPyV and complex organic molecule 1,1(')-didodecyl-3,3,3('),3(')-tetramethylindocarbocyanine perchlorate (DiI) is carried out. The theoretical distributions are able to describe those found in an experiment.
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Affiliation(s)
- I S Osad'ko
- Lebedev Physical Institute, RAS, 119991 Moscow, Russia.
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115
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Pina J, Seixas de Melo J, Burrows HD, Maçanita AL, Galbrecht F, Bünnagel T, Scherf U. Alternating Binaphthyl−Thiophene Copolymers: Synthesis, Spectroscopy, and Photophysics and Their Relevance to the Question of Energy Migration versus Conformational Relaxation. Macromolecules 2009. [DOI: 10.1021/ma802395c] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. Pina
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - J. Seixas de Melo
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - H. D. Burrows
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - A. L. Maçanita
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - F. Galbrecht
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - T. Bünnagel
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
| | - U. Scherf
- Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal, Departamento de Engenharia Química e Biológica, Centro de Química Estrutural, Instituto Superior Técnico, Av. Rovisco Pais, s/n. Lisboa, Portugal, and Makromolekulare Chemie, Bergische Universität Wuppertal, Gaussstr. 20, 42097 Wuppertal, Germany
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116
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Carroll EC, Hill MP, Madsen D, Malley KR, Larsen DS. A single source femtosecond-millisecond broadband spectrometer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:026102. [PMID: 19256678 DOI: 10.1063/1.3070516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Time-resolved measurement of population dynamics extending over femtosecond to millisecond time scales typically requires a combination of transient absorption techniques involving different laser systems and detection schemes. The spectrometer design presented here facilitates transient absorption measurements over 12 decades with a single ultrafast laser system by picking pump and probe pulses independently from the laser oscillator pulse train. Unamplified pulses seed a photonic crystal fiber to a supercontinuum probe source for spectrally resolved measurements. The utility of the system is demonstrated by measuring triplet state dynamics following photoexcitation of vitamin B(6) in aqueous solution.
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Affiliation(s)
- E C Carroll
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, USA
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117
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De Leener C, Hennebicq E, Sancho-Garcia JC, Beljonne D. Modeling the Dynamics of Chromophores in Conjugated Polymers: The Case of Poly(2-methoxy-5-(2′-ethylhexyl)oxy 1,4-phenylene vinylene) (MEH-PPV). J Phys Chem B 2009; 113:1311-22. [DOI: 10.1021/jp8029902] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Caroline De Leener
- Laboratory for Chemistry of Novel Materials, University of Mons-Hainaut, 20 Place du Parc, B-7000 Mons, Belgium, and Departamento de Química Física, Universidad de Alicante, E-03080 Alicante, Spain
| | - Emmanuelle Hennebicq
- Laboratory for Chemistry of Novel Materials, University of Mons-Hainaut, 20 Place du Parc, B-7000 Mons, Belgium, and Departamento de Química Física, Universidad de Alicante, E-03080 Alicante, Spain
| | - Juan-Carlos Sancho-Garcia
- Laboratory for Chemistry of Novel Materials, University of Mons-Hainaut, 20 Place du Parc, B-7000 Mons, Belgium, and Departamento de Química Física, Universidad de Alicante, E-03080 Alicante, Spain
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons-Hainaut, 20 Place du Parc, B-7000 Mons, Belgium, and Departamento de Química Física, Universidad de Alicante, E-03080 Alicante, Spain
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118
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Law M, Beard MC, Choi S, Luther JM, Hanna MC, Nozik AJ. Determining the internal quantum efficiency of PbSe nanocrystal solar cells with the aid of an optical model. NANO LETTERS 2008; 8:3904-3910. [PMID: 18823149 DOI: 10.1021/nl802353x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We determine the internal quantum efficiency (IQE) of the active layer of PbSe nanocrystal (NC) back-contact Schottky solar cells by combining external quantum efficiency (EQE) and total reflectance measurements with an optical model of the device stack. The model is parametrized with the complex index of refraction of each layer in the stack as calculated from ellipsometry data. Good agreement between the experimental and modeled reflectance spectra permits a quantitative estimate of the fraction of incident light absorbed by the NC films at each wavelength, thereby yielding well-constrained QE spectra for photons absorbed only by the NCs. Using a series of devices fabricated from 5.1+/-0.4 nm diameter PbSe NCs, we show that thin NC cells achieve an EQE and an active layer IQE as high as 60+/-5% and 80+/-7%, respectively, while the QE of devices with NC layers thicker than about 150 nm falls, particularly in the blue, because of progressively greater light absorption in the field-free region of the films and enhanced recombination overall. Our results demonstrate that interference effects must be taken into account in order to calculate accurate optical generation profiles and IQE spectra for these thin film solar cells. The mixed modeling/experimental approach described here is a rigorous and powerful way to determine if multiple exciton generation (MEG) photocurrent is collected by devices with EQE<100%. On the basis of the magnitudes and shapes of the IQE spectra, we conclude that the 1,2-ethanedithiol treated NC devices studied here do not produce appreciable MEG photocurrent.
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Affiliation(s)
- Matt Law
- National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
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119
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Sancho-García JC, Pérez-Jiménez AJ. Accurate calculation of transport properties for organic molecular semiconductors with spin-component scaled MP2 and modern density functional theory methods. J Chem Phys 2008; 129:024103. [DOI: 10.1063/1.2951991] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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120
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Abstract
Herein, we focus on the principles of photoconduction in random semiconductors-the key processes being optical generation of charge carriers and their subsequent transport. This is not an overview of the current work in this area, but rather a highlight of elementary processes, their involvement in modern devices and a summary of recent developments and achievements. Experimental results and models are discussed briefly to visualize the mechanism of optical charge generation in pure and doped organic solids. We show current limits of models based on the Onsager theory of charge generation. After the introduction of experimental techniques to characterize charge transport, the hopping concept for transport in organic semiconductors is outlined. The peculiarities of the transport of excitons and charges in disorderd organic semiconductors are highlighted. Finally, a short discussion of ultrafast transport and single chain transport completes the review.
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Affiliation(s)
- Dirk Hertel
- Institute of Physical Chemistry, University of Cologne, Luxemburger Str. 116, 50939 Cologne, Germany.
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121
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Lin H, Tabaei SR, Thomsson D, Mirzov O, Larsson PO, Scheblykin IG. Fluorescence Blinking, Exciton Dynamics, and Energy Transfer Domains in Single Conjugated Polymer Chains. J Am Chem Soc 2008; 130:7042-51. [DOI: 10.1021/ja800153d] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hongzhen Lin
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Seyed R. Tabaei
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Daniel Thomsson
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Oleg Mirzov
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Per-Olof Larsson
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Ivan G. Scheblykin
- Chemical Physics and Pure and Applied Biochemistry, Lund University, Box 124, 22100 Lund, Sweden
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122
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Dias FB, King S, Monkman AP, Perepichka II, Kryuchkov MA, Perepichka IF, Bryce MR. Dipolar Stabilization of Emissive Singlet Charge Transfer Excited States in Polyfluorene Copolymers. J Phys Chem B 2008; 112:6557-66. [DOI: 10.1021/jp800068d] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fernando B. Dias
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Simon King
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Andrew P. Monkman
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Irene I. Perepichka
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Maxim A. Kryuchkov
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Igor F. Perepichka
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
| | - Martin R. Bryce
- OEM Research Group, Department of Physics, Durham University, Durham DH1 3LE, U.K., Department of Chemistry, Durham University, Durham DH1 3LE, U.K., and Centre for Materials Science, Faculty of Science and Technology, University of Central Lancashire, Preston PR1 2HE, U.K
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Becker K, Fritzsche M, Höger S, Lupton JM. Phenylene−Ethynylene Macrocycles as Model Systems of Interchromophoric Interactions in π-Conjugated Macromolecules. J Phys Chem B 2008; 112:4849-53. [DOI: 10.1021/jp800160h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- K. Becker
- Photonics and Optoelectronics Group, Physics Department and CeNS, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany
| | - M. Fritzsche
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - S. Höger
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - J. M. Lupton
- Department of Physics, University of Utah, Salt Lake City, Utah 84112
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Scholes GD. Insights into excitons confined to nanoscale systems: electron-hole interaction, binding energy, and photodissociation. ACS NANO 2008; 2:523-537. [PMID: 19206579 DOI: 10.1021/nn700179k] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The characteristics of nanoscale excitons--the primary excited states of nanoscale systems like conjugated polymers, molecular aggregates, carbon nanotubes, and nanocrystalline quantum dots--are examined through exploration of model systems. On the basis of a valence bond-type model, an intuition is developed for understanding and comparing nanoscale systems. In particular, electron-hole interactions are examined in detail, showing how and why they affect spectroscopy and properties such as binding energy. The relationship between the bound exciton states and the nanoscale analogue of free carriers (charge-transfer exciton states) is developed. It is shown why the electron and hole act as independent particles in this manifold of states. The outlook for the field is discussed on the basis of the picture developed in the paper, with an emphasis on exciton binding and photodissociation.
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Affiliation(s)
- Gregory D Scholes
- Department of Chemistry, 80 St. George Street, Institute for Optical Sciences, and Centre for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada.
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125
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Nakamura T, Araki Y, Ito O, Takimiya K, Otsubo T. Fluorescence Up-Conversion Study of Excitation Energy Transport Dynamics in Oligothiophene−Fullerene Linked Dyads. J Phys Chem A 2008; 112:1125-32. [DOI: 10.1021/jp710115z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Takumi Nakamura
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai, Miyagi 980-8577, Japan, and Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Yasuyuki Araki
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai, Miyagi 980-8577, Japan, and Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Osamu Ito
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai, Miyagi 980-8577, Japan, and Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Kazuo Takimiya
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai, Miyagi 980-8577, Japan, and Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Tetsuo Otsubo
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai, Miyagi 980-8577, Japan, and Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
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126
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Sun M, Ding Y, Xu H. Direct Visual Evidence for Quinoidal Charge Delocalization in Poly-p-phenylene Cation Radical. J Phys Chem B 2007; 111:13266-70. [DOI: 10.1021/jp076542l] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mengtao Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603-146, Beijing, 100080, P. R. China, Department of Physics, Liaoning University, Shenyang,110036, China, Department of Physics, Peking University, Beijing,100871, P. R. China, and Division of Solid State Physics, Lund University, Lund 22100, Sweden
| | - Yong Ding
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603-146, Beijing, 100080, P. R. China, Department of Physics, Liaoning University, Shenyang,110036, China, Department of Physics, Peking University, Beijing,100871, P. R. China, and Division of Solid State Physics, Lund University, Lund 22100, Sweden
| | - Hongxing Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603-146, Beijing, 100080, P. R. China, Department of Physics, Liaoning University, Shenyang,110036, China, Department of Physics, Peking University, Beijing,100871, P. R. China, and Division of Solid State Physics, Lund University, Lund 22100, Sweden
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Gulbinas V, Minevičiūtė I, Hertel D, Wellander R, Yartsev A, Sundström V. Exciton diffusion and relaxation in methyl-substituted polyparaphenylene polymer films. J Chem Phys 2007; 127:144907. [DOI: 10.1063/1.2790901] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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