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Asandulesa M, Kostromin S, Aleksandrov A, Tameev A, Bronnikov S. The effect of PbS quantum dots on molecular dynamics and conductivity of PTB7:PC71BM bulk heterojunction as revealed by dielectric spectroscopy. Phys Chem Chem Phys 2022; 24:9589-9596. [PMID: 35403182 DOI: 10.1039/d2cp00770c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A ternary photovoltaic blend containing the PTB7 donor component, the PC71BM acceptor component, and colloidal quantum dots of lead sulfide (PbS QDs) was investigated using broadband dielectric spectroscopy. In the dielectric loss spectrum of PTB7:PC71BM:PbS QDs, γ- and β-relaxation processes in PTB7 were recognized and analyzed in terms of Arrhenius-type equations. To elucidate the effect of PbS QDs on molecular dynamics of PTB7, the activation energies of both processes were evaluated and compared with those obtained for the binary PTB7:PC71BM blend. Using the CELIV method, the charge carrier mobility was estimated. The PbS QD incorporation into the binary blend was shown to decrease both electron and hole mobility in the ternary PTB7:PC71BM:PbS QD blend. For evaluating the charge carrier lifetime in the ternary blend, the Cole-Cole diagrams derived from the dc conductivity data were plotted. The charge carrier lifetime was found to be much less than the hole extraction time, thus providing effective accumulation of charge carries at the electrodes in the ternary blend under investigation.
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Affiliation(s)
- Mihai Asandulesa
- Romanian Academy, Petru Poni Institute of Macromolecular Chemistry, Iaşi 700487, Romania
| | - Sergei Kostromin
- Russian Academy of Sciences, Institute of Macromolecular Compounds, St. Petersburg 199004, Russian Federation.
| | - Alexey Aleksandrov
- Russian Academy of Sciences, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Moscow 119071, Russian Federation
| | - Alexey Tameev
- Russian Academy of Sciences, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Moscow 119071, Russian Federation
| | - Sergei Bronnikov
- Russian Academy of Sciences, Institute of Macromolecular Compounds, St. Petersburg 199004, Russian Federation.
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Schwaiger DM, Lohstroh W, Müller-Buschbaum P. The Influence of the Blend Ratio, Solvent Additive, and Post-production Treatment on the Polymer Dynamics in PTB7:PCBM Blend Films. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dominik M. Schwaiger
- Physik-Department, Technische Universität München, Lehrstuhl für Funktionelle Materialien James-Franck-Straße 1, 85748 Garching, Germany
| | - Wiebke Lohstroh
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
| | - Peter Müller-Buschbaum
- Physik-Department, Technische Universität München, Lehrstuhl für Funktionelle Materialien James-Franck-Straße 1, 85748 Garching, Germany
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
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Cassella G, Stewart JR, Paternò GM, García Sakai V, Devonport M, Galsworthy PJ, Bewley RI, Voneshen DJ, Raspino D, Nilsen GJ. Polarization analysis on the LET cold neutron spectrometer using a 3He spin-filter: first results. ACTA ACUST UNITED AC 2019. [DOI: 10.1088/1742-6596/1316/1/012007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
We report on the design and construction of a neutron polarization analyzer based on a 3He spin filter for the LET spectrometer at the ISIS facility. Its commissioning completes the uniaxial polarized mode of the instrument. Besides the 3He spin filter cell, the analyzer consists of a set of electromagnetic coils to provide a uniform magnetic field, and a collimator to eliminate background from the sample environment and analyzer infrastructure. The 3He cell is separated from the LET main tank vacuum by means of a gas tank, which permits rapid cell changeovers and guarantees safe operation. In addition to the analyzer hardware, software has been written to reduce and correct polarized data. The successful operation of the polarized mode was realized for the separation of coherent and incoherent dynamics in an organic solar cell polymer blend.
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Cavaye H. Neutron Spectroscopy: An Under-Utilised Tool for Organic Electronics Research? Angew Chem Int Ed Engl 2019; 58:9338-9346. [PMID: 30561867 DOI: 10.1002/anie.201812950] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Indexed: 11/08/2022]
Abstract
Neutron scattering is a well-established technique that has proven to be an invaluable tool in myriad fields of chemical and physical research. Neutrons offer unique ways to study in situ or operando functional materials due to their highly penetrating nature and specific interactions with the nuclei of different isotopes. While some neutron scattering techniques, such as neutron diffraction (ND), neutron reflectometry (NR), and small-angle neutron scattering (SANS), have already been heavily adopted by the scientific community for use in the research of organic electronics, there are a number of techniques that are far less widely used: spectroscopic neutron scattering. This article aims to highlight these "under-utilised" techniques, to emphasise their potential use within the field of organic electronics, and to increase awareness of their utility among new research communities.
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Affiliation(s)
- Hamish Cavaye
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Science and Technology Facilities Council, Didcot, OX11 0QX, UK
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Cavaye H. Neutron Spectroscopy: An Under‐Utilised Tool for Organic Electronics Research? Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201812950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Hamish Cavaye
- ISIS Neutron and Muon SourceRutherford Appleton LaboratoryScience and Technology Facilities Council Didcot OX11 0QX UK
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Wolf CM, Kanekal KH, Yimer YY, Tyagi M, Omar-Diallo S, Pakhnyuk V, Luscombe CK, Pfaendtner J, Pozzo LD. Assessment of molecular dynamics simulations for amorphous poly(3-hexylthiophene) using neutron and X-ray scattering experiments. SOFT MATTER 2019; 15:5067-5083. [PMID: 31183486 DOI: 10.1039/c9sm00807a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The molecular morphology and dynamics of conjugated polymers in the bulk solid state play a significant role in determining macroscopic charge transport properties. To understand this relationship, molecular dynamics (MD) simulations and quantum mechanical calculations are used to evaluate local electronic properties. In this work, we investigate the importance of system and simulation parameters, such as force fields and equilibration methods, when simulating amorphous poly(3-hexylthiophene) (P3HT), a model semiconducting polymer. An assessment of MD simulations for five different published P3HT force fields is made by comparing results to experimental wide-angle X-ray scattering (WAXS) and to a broad range of quasi-elastic neutron scattering (QENS) data. Moreover, an in silico analysis of force field parameters reveals that atomic partial charges and torsion potentials along the backbone and side chains have the greatest impact on structure and dynamics related to charge transport mechanisms in P3HT.
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Affiliation(s)
- Caitlyn M Wolf
- Department of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195-1750, USA.
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Guilbert AAY, Zbiri M, Dunbar ADF, Nelson J. Quantitative Analysis of the Molecular Dynamics of P3HT:PCBM Bulk Heterojunction. J Phys Chem B 2017; 121:9073-9080. [PMID: 28834430 DOI: 10.1021/acs.jpcb.7b08312] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The optoelectronic properties of blends of conjugated polymers and small molecules are likely to be affected by the molecular dynamics of the active layer components. We study the dynamics of regioregular poly(3-hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester (PCBM) blends using molecular dynamics (MD) simulation on time scales up to 50 ns and in a temperature range of 250-360 K. First, we compare the MD results with quasi-elastic neutron-scattering (QENS) measurements. Experiment and simulation give evidence of the vitrification of P3HT upon blending and the plasticization of PCBM by P3HT. Second, we reconstruct the QENS signal based on the independent simulations of the three phases constituting the complex microstructure of such blends. Finally, we found that P3HT chains tend to wrap around PCBM molecules in the amorphous mixture of P3HT and PCBM; this molecular interaction between P3HT and PCBM is likely to be responsible for the observed frustration of P3HT, the plasticization of PCBM, and the partial miscibility of P3HT and PCBM.
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Affiliation(s)
- Anne A Y Guilbert
- Centre for Plastic Electronics and Department of Physics, Blackett Laboratory, Imperial College London , London SW7 2AZ, United Kingdom
| | - Mohamed Zbiri
- Institut Laue-Langevin , 71 avenue des Martyrs, Grenoble Cedex 9, 38042 France
| | - Alan D F Dunbar
- Department of Chemical and Biological Engineering, The University of Sheffield , Sheffield S1 3JD, United Kingdom
| | - Jenny Nelson
- Centre for Plastic Electronics and Department of Physics, Blackett Laboratory, Imperial College London , London SW7 2AZ, United Kingdom
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Guilbert AAY, Zbiri M, Jenart MVC, Nielsen CB, Nelson J. New Insights into the Molecular Dynamics of P3HT:PCBM Bulk Heterojunction: A Time-of-Flight Quasi-Elastic Neutron Scattering Study. J Phys Chem Lett 2016; 7:2252-2257. [PMID: 27192930 DOI: 10.1021/acs.jpclett.6b00537] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The molecular dynamics of organic semiconductor blend layers are likely to affect the optoelectronic properties and the performance of devices such as solar cells. We study the dynamics (5-50 ps) of the poly(3-hexylthiophene) (P3HT): phenyl-C61-butyric acid methyl ester (PCBM) blend by time-of-flight quasi-elastic neutron scattering, at temperatures in the range 250-360 K, thus spanning the glass transition temperature region of the polymer and the operation temperature of an OPV device. The behavior of the QENS signal provides evidence for the vitrification of P3HT upon blending, especially above the glass transition temperature, and the plasticization of PCBM by P3HT, both dynamics occurring on the picosecond time scale.
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Affiliation(s)
- Anne A Y Guilbert
- Centre for Plastic Electronics and Department of Physics, Blackett Laboratory, Imperial College London , London SW7 2AZ, United Kingdom
| | - Mohamed Zbiri
- Institut Laue-Langevin , 71 avenue des Martyrs, Grenoble Cedex 9, 38042, France
| | - Maud V C Jenart
- Centre for Plastic Electronics and Department of Chemistry, Imperial College London , London SW7 2AZ, United Kingdom
| | - Christian B Nielsen
- Centre for Plastic Electronics and Department of Chemistry, Imperial College London , London SW7 2AZ, United Kingdom
- Materials Research Institute and School of Biological and Chemical Sciences, Queen Mary University of London , Mile End Road, London E1 4NS, United Kingdom
| | - Jenny Nelson
- Centre for Plastic Electronics and Department of Physics, Blackett Laboratory, Imperial College London , London SW7 2AZ, United Kingdom
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