51
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Paterson AF, Singh S, Fallon KJ, Hodsden T, Han Y, Schroeder BC, Bronstein H, Heeney M, McCulloch I, Anthopoulos TD. Recent Progress in High-Mobility Organic Transistors: A Reality Check. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1801079. [PMID: 30022536 DOI: 10.1002/adma.201801079] [Citation(s) in RCA: 218] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 04/10/2018] [Indexed: 05/27/2023]
Abstract
Over the past three decades, significant research efforts have focused on improving the charge carrier mobility of organic thin-film transistors (OTFTs). In recent years, a commonly observed nonlinearity in OTFT current-voltage characteristics, known as the "kink" or "double slope," has led to widespread mobility overestimations, contaminating the relevant literature. Here, published data from the past 30 years is reviewed to uncover the extent of the field-effect mobility hype and identify the progress that has actually been achieved in the field of OTFTs. Present carrier-mobility-related challenges are identified, finding that reliable hole and electron mobility values of 20 and 10 cm2 V-1 s-1 , respectively, have yet to be achieved. Based on the analysis, the literature is then reviewed to summarize the concepts behind the success of high-performance p-type polymers, along with the latest understanding of the design criteria that will enable further mobility enhancement in n-type polymers and small molecules, and the reasons why high carrier mobility values have been consistently produced from small molecule/polymer blend semiconductors. Overall, this review brings together important information that aids reliable OTFT data analysis, while providing guidelines for the development of next-generation organic semiconductors.
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Affiliation(s)
- Alexandra F Paterson
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Saumya Singh
- Department of Chemistry, University College London, London, WC1H 0AJ, UK
| | - Kealan J Fallon
- Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Thomas Hodsden
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Yang Han
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Bob C Schroeder
- Department of Chemistry, University College London, London, WC1H 0AJ, UK
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Martin Heeney
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Iain McCulloch
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Thomas D Anthopoulos
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
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52
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Matsuda W, Sakurai T, Ghosh G, Ghosh S, Seki S. Transient Optical-Microwave Spectroscopy for Electron Mobility Assessment in Solids and Gels: A Comprehensive Approach. J PHOTOPOLYM SCI TEC 2018. [DOI: 10.2494/photopolymer.31.91] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Wakana Matsuda
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
| | - Tsuneaki Sakurai
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
| | - Goutam Ghosh
- Polymer Science Unit, Indian Association for the Cultivation of Science
| | - Suhrit Ghosh
- Polymer Science Unit, Indian Association for the Cultivation of Science
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
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53
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Nishinaga S, Mori H, Nishihara Y. Synthesis and Transistor Application of Bis[1]benzothieno[6,7-d:6′,7′-d′]benzo[1,2-b:4,5-b′]dithiophenes. J Org Chem 2018; 83:5506-5515. [DOI: 10.1021/acs.joc.8b00483] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shuhei Nishinaga
- Division of Earth, Life, and Molecular Sciences, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Hiroki Mori
- Research Institute for Interdisciplinary Science, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Yasushi Nishihara
- Research Institute for Interdisciplinary Science, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
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54
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Jiang H, Hu P, Ye J, Chaturvedi A, Zhang KK, Li Y, Long Y, Fichou D, Kloc C, Hu W. From Linear to Angular Isomers: Achieving Tunable Charge Transport in Single-Crystal Indolocarbazoles Through Delicate Synergetic CH/NH⋅⋅⋅π Interactions. Angew Chem Int Ed Engl 2018; 57:8875-8880. [PMID: 29457325 DOI: 10.1002/anie.201713288] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/13/2018] [Indexed: 11/08/2022]
Abstract
Weak intermolecular interaction in organic semiconducting molecular crystals plays an important role in molecular packing and electronic properties. Here, four five-ring-fused isomers were rationally designed and synthesized to investigate the isomeric influence of linear and angular shapes in affecting their molecular packing and resultant electronic properties. Single-crystal field-effect transistors showed mobility order of 5,7-ICZ (3.61 cm2 V-1 s-1 ) >5,11-ICZ (0.55 cm2 V-1 s-1 ) >11,12-ICZ (ca. 10-5 cm2 V-1 s-1 ) and 5,12-ICZ (ca. 10-6 cm2 V-1 s-1 ). Theoretical calculations based on density functional theory (DFT) and polaron transport model revealed that 5,7-ICZ can reach higher mobilities than the others thanks to relatively higher hole transfer integral that links to stronger intermolecular interaction due to the presence of multiple NH⋅⋅⋅π and CH⋅⋅⋅π(py) interactions with energy close to common NH⋅⋅⋅N hydrogen bonds, as well as overall lower hole-vibrational coupling owing to the absence of coupling of holes to low frequency modes due to better π conjugation.
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Affiliation(s)
- Hui Jiang
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore.,School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore, Singapore
| | - Peng Hu
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Jun Ye
- Institute of High Performance Computing, Agency for Science, Technology and Research, 138632 Singapore, Singapore
| | - Apoorva Chaturvedi
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Keke K Zhang
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Yongxin Li
- School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore, Singapore
| | - Yi Long
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Denis Fichou
- School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore, Singapore.,Sorbonne Universités, UPMC Univ Paris 06, UMR 8232, Institut Parisien de Chimie Moléculaire, 75005, Paris, France.,CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Christian Kloc
- School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Wenping Hu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University and Collaborative Innovation Center of, Chemical Science and Engineering (Tianjin), Tianjin, 300072, China
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55
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Jiang H, Hu P, Ye J, Chaturvedi A, Zhang KK, Li Y, Long Y, Fichou D, Kloc C, Hu W. From Linear to Angular Isomers: Achieving Tunable Charge Transport in Single-Crystal Indolocarbazoles Through Delicate Synergetic CH/NH⋅⋅⋅π Interactions. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713288] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Hui Jiang
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
- School of Physical and Mathematical Sciences; Nanyang Technological University; 637371 Singapore Singapore
| | - Peng Hu
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
| | - Jun Ye
- Institute of High Performance Computing; Agency for Science; Technology and Research; 138632 Singapore Singapore
| | - Apoorva Chaturvedi
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
| | - Keke K. Zhang
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
| | - Yongxin Li
- School of Physical and Mathematical Sciences; Nanyang Technological University; 637371 Singapore Singapore
| | - Yi Long
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
| | - Denis Fichou
- School of Physical and Mathematical Sciences; Nanyang Technological University; 637371 Singapore Singapore
- Sorbonne Universités; UPMC Univ Paris 06; UMR 8232; Institut Parisien de Chimie Moléculaire; 75005 Paris France
- CNRS; UMR 8232; Institut Parisien de Chimie Moléculaire; 75005 Paris France
| | - Christian Kloc
- School of Materials Science and Engineering; Nanyang Technological University; 639798 Singapore Singapore
| | - Wenping Hu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences; Department of Chemistry; School of Science; Tianjin University and Collaborative Innovation Center of, Chemical Science and Engineering (Tianjin); Tianjin 300072 China
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56
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Yavuz I. Dichotomy between the band and hopping transport in organic crystals: insights from experiments. Phys Chem Chem Phys 2018; 19:25819-25828. [PMID: 28932847 DOI: 10.1039/c7cp05297a] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular understanding of charge-transport in organic crystals has often been tangled with identifying the true dynamical origin. While in two distinct cases where complete delocalization and localization of charge-carriers are associated with band-like and hopping-like transports, respectively, their possible coalescence poses some mystery. Moreover, the existing models are still controversial at ambient temperatures. Here, we review the issues in charge-transport theories of organic materials and then provide an overview of prominent transport models. We explored ∼60 organic crystals, the single-crystal hole/electron mobilities of which have been predicted by band-like and hopping-like transport models, separately. Our comparative results show that at room-temperature neither of the models are exclusively capable of accurately predicting mobilities in a very broad range. Hopping-like models well-predict experimental mobilities around μ ∼ 1 cm2 V-1 s-1 but systematically diverge at high mobilities. Similarly, band-like models are good at μ > ∼50 cm2 V-1 s-1 but systematically diverge at lower mobilities. These results suggest the development of a unique and robust room-temperature transport model incorporating a mixture of these two extreme cases, whose relative importance is associated with their predominant regions. We deduce that while band models are beneficial for rationally designing high mobility organic-semiconductors, hopping models are good to elucidate the charge-transport of most organic-semiconductors.
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Affiliation(s)
- I Yavuz
- Marmara University, Physics Dep., Ziverbey, 34722, Istanbul, Turkey.
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57
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Ji LF, Fan JX, Zhang SF, Ren AM. Theoretical study on the charge transport in single crystals of TCNQ, F 2-TCNQ and F 4-TCNQ. Phys Chem Chem Phys 2018; 20:3784-3794. [PMID: 29349447 DOI: 10.1039/c7cp07189b] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
2,5-Difluoro-7,7,8,8-tetracyanoquinodimethane (F2-TCNQ) was recently reported to display excellent electron transport properties in single crystal field-effect transistors (FETs). Its carrier mobility can reach 25 cm2 V-1 s-1 in devices. However, its counterparts TCNQ and F4-TCNQ (tetrafluoro-7,7,8,8-tetracyanoquinodimethane) do not exhibit the same highly efficient behavior. To better understand this significant difference in charge carrier mobility, a multiscale approach combining semiclassical Marcus hopping theory, a quantum nuclear enabled hopping model and molecular dynamics simulations was performed to assess the electron mobilities of the Fn-TCNQ (n = 0, 2, 4) systems in this work. The results indicated that the outstanding electron transport behavior of F2-TCNQ arises from its effective 3D charge carrier percolation network due to its special packing motif and the nuclear tunneling effect. Moreover, the poor transport properties of TCNQ and F4-TCNQ stem from their invalid packing and strong thermal disorder. It was found that Marcus theory underestimated the mobilities for all the systems, while the quantum model with the nuclear tunneling effect provided reasonable results compared to experiments. Moreover, the band-like transport behavior of F2-TCNQ was well described by the quantum nuclear enabled hopping model. In addition, quantum theory of atoms in molecules (QTAIM) analysis and symmetry-adapted perturbation theory (SAPT) were used to characterize the intermolecular interactions in TCNQ, F2-TCNQ and F4-TCNQ crystals. A primary understanding of various noncovalent interaction responses for crystal formation is crucial to understand the structure-property relationships in organic molecular materials.
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Affiliation(s)
- Li-Fei Ji
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, China.
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58
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Nakazato T, Kamatsuka T, Inoue J, Sakurai T, Seki S, Shinokubo H, Miyake Y. The reductive aromatization of naphthalene diimide: a versatile platform for 2,7-diazapyrenes. Chem Commun (Camb) 2018; 54:5177-5180. [DOI: 10.1039/c8cc01937a] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The reductive aromatization of naphthalene diimide provides tetrapivaloxy-2,7-diazapyrene, which serves as a versatile platform toward peripherally substituted 2,7-diazapyrenes.
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Affiliation(s)
- Takumi Nakazato
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya 464-8603
- Japan
| | - Takuto Kamatsuka
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya 464-8603
- Japan
| | - Junichi Inoue
- Department of Molecular Engineering, Graduate School of Engineering
- Kyoto University
- Nishikyo-ku
- Kyoto 615-8510
- Japan
| | - Tsuneaki Sakurai
- Department of Molecular Engineering, Graduate School of Engineering
- Kyoto University
- Nishikyo-ku
- Kyoto 615-8510
- Japan
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering
- Kyoto University
- Nishikyo-ku
- Kyoto 615-8510
- Japan
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya 464-8603
- Japan
| | - Yoshihiro Miyake
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya 464-8603
- Japan
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59
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Alkan M, Yavuz I. Intrinsic charge-mobility in benzothieno[3,2-b][1]benzothiophene (BTBT) organic semiconductors is enhanced with long alkyl side-chains. Phys Chem Chem Phys 2018; 20:15970-15979. [DOI: 10.1039/c8cp01640b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Longer alkyl side-chains in BTBTs regulate structural order, cause balanced transport and lead to enhanced intrinsic charge-carrier mobility.
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Affiliation(s)
- M. Alkan
- Physics Department
- Marmara University
- Ziverbey
- Turkey
| | - I. Yavuz
- Physics Department
- Marmara University
- Ziverbey
- Turkey
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60
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Lin Z, Yang X, Xu H, Sakurai T, Matsuda W, Seki S, Zhou Y, Sun J, Wu KY, Yan XY, Zhang R, Huang M, Mao J, Wesdemiotis C, Aida T, Zhang W, Cheng SZD. Topologically Directed Assemblies of Semiconducting Sphere–Rod Conjugates. J Am Chem Soc 2017; 139:18616-18622. [DOI: 10.1021/jacs.7b10193] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhiwei Lin
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Xing Yang
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Hui Xu
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Tsuneaki Sakurai
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Wakana Matsuda
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Shu Seki
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Yangbin Zhou
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Jian Sun
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Kuan-Yi Wu
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Xiao-Yun Yan
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Ruimeng Zhang
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Mingjun Huang
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Jialin Mao
- Department
of Chemistry, The University of Akron, Akron, Ohio 44325, United States
| | - Chrys Wesdemiotis
- Department
of Chemistry, The University of Akron, Akron, Ohio 44325, United States
| | - Takuzo Aida
- Department
of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Wei Zhang
- South
China Advanced Institute for Soft Matter Science and Technology, South China University of Technology, Guangzhou 510640, China
| | - Stephen Z. D. Cheng
- Department
of Polymer Science, College of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
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61
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Choi W, Tsutsui Y, Miyakai T, Sakurai T, Seki S. Quantitative evaluation of spatial scale of carrier trapping at grain boundary by GHz-microwave dielectric loss spectroscopy. ACTA ACUST UNITED AC 2017. [DOI: 10.1088/1742-6596/924/1/012002] [Citation(s) in RCA: 2] [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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62
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Sakurai T, Yoneda S, Sakaguchi S, Kato K, Takata M, Seki S. Donor/Acceptor Segregated π-Stacking Arrays by Use of Shish-Kebab-Type Polymeric Backbones: Highly Conductive Discotic Blends of Phthalocyaninatopolysiloxanes and Perylenediimides. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b02020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Tsuneaki Sakurai
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Satoru Yoneda
- Department
of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shugo Sakaguchi
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Kenichi Kato
- Materials
Visualization Photon Science Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Masaki Takata
- Materials
Visualization Photon Science Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Shu Seki
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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63
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Arend TR, Wimmer A, Schweicher G, Chattopadhyay B, Geerts YH, Kersting R. Band Transport and Trapping in Didodecyl[1]benzothieno[3,2-b][1]benzothiophene Probed by Terahertz Spectroscopy. J Phys Chem Lett 2017; 8:5444-5449. [PMID: 29058437 DOI: 10.1021/acs.jpclett.7b02304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Terahertz electromodulation spectroscopy provides insight into the material-inherent transport properties of charge carriers in organic semiconductors. Experiments on didodecyl[1]benzothieno[3,2-b][1]benzothiophene (C12-BTBT-C12) devices yield for holes an intraband mobility of 9 cm2 V-1 s-1. The short duration of the THz pulses advances the understanding of the hole transport on the molecular scale. The efficient screening of Coulomb potentials leads to a collective response of the hole gas to external fields, which can be well described by the Drude model. Bias stress of the devices generates deep traps that capture mobile holes. Although the resulting polarization across the device hinders the injection of mobile holes, the hole mobilities are not affected.
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Affiliation(s)
- Thomas R Arend
- Faculty of Physics and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Amalienstr. 54, 80799 München, Germany
| | - Andreas Wimmer
- Faculty of Physics and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Amalienstr. 54, 80799 München, Germany
| | - Guillaume Schweicher
- Laboratoire de chimie des polyméres, Faculté des Sciences, Université Libre de Bruxelles , ULB Boulevard du Triomphe, Brussels 1050, Belgium
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge , JJ Thomson Avenue, Cambridge CB3 0HE, United-Kingdom
| | - Basab Chattopadhyay
- Laboratoire de chimie des polyméres, Faculté des Sciences, Université Libre de Bruxelles , ULB Boulevard du Triomphe, Brussels 1050, Belgium
| | - Yves H Geerts
- Laboratoire de chimie des polyméres, Faculté des Sciences, Université Libre de Bruxelles , ULB Boulevard du Triomphe, Brussels 1050, Belgium
| | - Roland Kersting
- Faculty of Physics and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Amalienstr. 54, 80799 München, Germany
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64
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Méndez-Ardoy A, Markandeya N, Li X, Tsai YT, Pecastaings G, Buffeteau T, Maurizot V, Muccioli L, Castet F, Huc I, Bassani DM. Multi-dimensional charge transport in supramolecular helical foldamer assemblies. Chem Sci 2017; 8:7251-7257. [PMID: 29147547 PMCID: PMC5633016 DOI: 10.1039/c7sc03341a] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/04/2017] [Indexed: 11/21/2022] Open
Abstract
Aromatic foldamers are bioinspired architectures whose potential use in materials remains largely unexplored. Here we report our investigation of vertical and horizontal charge transport over long distances in helical oligo-quinolinecarboxamide foldamers organized as single monolayers on Au or SiO2. Conductive atomic force microscopy showed that vertical conductivity is efficient and that it displays a low attenuation with foldamer length (0.06 Å-1). In contrast, horizontal charge transport is found to be negligible, demonstrating the strong anisotropy of foldamer monolayers. Kinetic Monte Carlo calculations were used to probe the mechanism of charge transport in these helical molecules and revealed the presence of intramolecular through-space charge transfer integrals approaching those found in pentacene and rubrene crystals, in line with experimental results. Kinetic Monte Carlo simulations of charge hopping along the foldamer chain evidence the strong contribution of multiple 1D and 3D pathways in these architectures and their dependence on conformational order. These findings show that helical foldamer architectures may provide a route for achieving charge transport over long distance by combining multiple charge transport pathways.
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Affiliation(s)
- Alejandro Méndez-Ardoy
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
| | - Nagula Markandeya
- Univ. Bordeaux CNRS UMR 5248 CBMN , 2 rue Escarpit , 33600 Pessac , France .
| | - Xuesong Li
- Univ. Bordeaux CNRS UMR 5248 CBMN , 2 rue Escarpit , 33600 Pessac , France .
| | - Yu-Tang Tsai
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
| | - Gilles Pecastaings
- Inst. Polytechnique de Bordeaux CNRS UMR 5629 LCPO , 16, Av. Pey-Berland , 33600 Pessac , France
| | - Thierry Buffeteau
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
| | - Victor Maurizot
- Univ. Bordeaux CNRS UMR 5248 CBMN , 2 rue Escarpit , 33600 Pessac , France .
| | - Luca Muccioli
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
| | - Frédéric Castet
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
| | - Ivan Huc
- Univ. Bordeaux CNRS UMR 5248 CBMN , 2 rue Escarpit , 33600 Pessac , France .
| | - Dario M Bassani
- Univ. Bordeaux CNRS UMR 5255 ISM , 351, Cours de la Libération , 33405 Talence , France .
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65
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Sandoval-Torrientes R, Calbo J, Matsuda W, Choi W, Santos J, Seki S, Ortí E, Martín N. Efficient Benzodithiophene/Benzothiadiazole-Based n-Channel Charge Transporters. Chempluschem 2017; 82:1105-1111. [PMID: 31961602 DOI: 10.1002/cplu.201700047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 02/22/2017] [Indexed: 11/06/2022]
Abstract
A series of donor-acceptor (D-A) small molecules based on electron-deficient benzothiadiazole (BTD) and electron-rich benzodithiophene (BDT) featuring an A-D-A structure is presented. Exhaustive spectroscopic, electrochemical, and computational studies evidence their electroactive nature and their ability to form well-ordered thin films with broad visible absorptions and low band gaps (ca. 2 eV). Time-resolved microwave conductivity (TRMC) studies unveil unexpected n-type charge transport displaying high electron mobilities around 0.1 cm2 V-1 s-1 . Efficient electron transport properties are consistent with the low electron reorganization energies (0.11-0.17 eV) theoretically predicted.
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Affiliation(s)
| | - Joaquín Calbo
- Instituto de Ciencia Molecular, Universidad de Valencia, 46980, Paterna, Spain
| | - Wakana Matsuda
- Department of Molecular Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Wookjin Choi
- Department of Molecular Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - José Santos
- Instituto Madrileño de Estudios Avanzados (IMDEA)-Nanociencia, c/ Faraday, 9, 28049, Madrid, Spain
| | - Shu Seki
- Department of Molecular Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Enrique Ortí
- Instituto de Ciencia Molecular, Universidad de Valencia, 46980, Paterna, Spain
| | - Nazario Martín
- Instituto Madrileño de Estudios Avanzados (IMDEA)-Nanociencia, c/ Faraday, 9, 28049, Madrid, Spain.,Departamento de Química Orgánica, Facultad de C. Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain
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66
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Trasobares J, Rech J, Jonckheere T, Martin T, Aleveque O, Levillain E, Diez-Cabanes V, Olivier Y, Cornil J, Nys JP, Sivakumarasamy R, Smaali K, Leclere P, Fujiwara A, Théron D, Vuillaume D, Clément N. Estimation of π-π Electronic Couplings from Current Measurements. NANO LETTERS 2017; 17:3215-3224. [PMID: 28358215 DOI: 10.1021/acs.nanolett.7b00804] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The π-π interactions between organic molecules are among the most important parameters for optimizing the transport and optical properties of organic transistors, light-emitting diodes, and (bio-) molecular devices. Despite substantial theoretical progress, direct experimental measurement of the π-π electronic coupling energy parameter t has remained an old challenge due to molecular structural variability and the large number of parameters that affect the charge transport. Here, we propose a study of π-π interactions from electrochemical and current measurements on a large array of ferrocene-thiolated gold nanocrystals. We confirm the theoretical prediction that t can be assessed from a statistical analysis of current histograms. The extracted value of t ≈35 meV is in the expected range based on our density functional theory analysis. Furthermore, the t distribution is not necessarily Gaussian and could be used as an ultrasensitive technique to assess intermolecular distance fluctuation at the subangström level. The present work establishes a direct bridge between quantum chemistry, electrochemistry, organic electronics, and mesoscopic physics, all of which were used to discuss results and perspectives in a quantitative manner.
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Affiliation(s)
- J Trasobares
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - J Rech
- Aix Marseille University, Universite de Toulon, CNRS, CPT , 163 Avenue de Luminy, 13288 Marseille cedex 9, France
| | - T Jonckheere
- Aix Marseille University, Universite de Toulon, CNRS, CPT , 163 Avenue de Luminy, 13288 Marseille cedex 9, France
| | - T Martin
- Aix Marseille University, Universite de Toulon, CNRS, CPT , 163 Avenue de Luminy, 13288 Marseille cedex 9, France
| | - O Aleveque
- Université d'Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou , 2 bd Lavoisier, 49045 Angers cedex, France
| | - E Levillain
- Université d'Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou , 2 bd Lavoisier, 49045 Angers cedex, France
| | - V Diez-Cabanes
- Laboratory for Chemistry of Novel Materials, University of Mons , Place du Parc 20, B-7000 Mons, Belgium
| | - Y Olivier
- Laboratory for Chemistry of Novel Materials, University of Mons , Place du Parc 20, B-7000 Mons, Belgium
| | - J Cornil
- Laboratory for Chemistry of Novel Materials, University of Mons , Place du Parc 20, B-7000 Mons, Belgium
| | - J P Nys
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - R Sivakumarasamy
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - K Smaali
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - P Leclere
- Laboratory for Chemistry of Novel Materials, University of Mons , Place du Parc 20, B-7000 Mons, Belgium
| | - A Fujiwara
- NTT Basic Research Laboratories, 3-1, Morinosato Wakamiya, Atsugi-shi, kanagawa 243-0198, Japan
| | - D Théron
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - D Vuillaume
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
| | - N Clément
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS, University of Lille , Avenue Poincaré, BP60069, 59652, Villeneuve d'Ascq France
- NTT Basic Research Laboratories, 3-1, Morinosato Wakamiya, Atsugi-shi, kanagawa 243-0198, Japan
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67
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Charge carrier mobility in thin films of organic semiconductors by the gated van der Pauw method. Nat Commun 2017; 8:14975. [PMID: 28397852 PMCID: PMC5394272 DOI: 10.1038/ncomms14975] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/14/2017] [Indexed: 11/08/2022] Open
Abstract
Thin film transistors based on high-mobility organic semiconductors are prone to contact problems that complicate the interpretation of their electrical characteristics and the extraction of important material parameters such as the charge carrier mobility. Here we report on the gated van der Pauw method for the simple and accurate determination of the electrical characteristics of thin semiconducting films, independently from contact effects. We test our method on thin films of seven high-mobility organic semiconductors of both polarities: device fabrication is fully compatible with common transistor process flows and device measurements deliver consistent and precise values for the charge carrier mobility and threshold voltage in the high-charge carrier density regime that is representative of transistor operation. The gated van der Pauw method is broadly applicable to thin films of semiconductors and enables a simple and clean parameter extraction independent from contact effects.
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68
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Takahashi K, Shan B, Xu X, Yang S, Koganezawa T, Kuzuhara D, Aratani N, Suzuki M, Miao Q, Yamada H. Engineering Thin Films of a Tetrabenzoporphyrin toward Efficient Charge-Carrier Transport: Selective Formation of a Brickwork Motif. ACS APPLIED MATERIALS & INTERFACES 2017; 9:8211-8218. [PMID: 28186397 DOI: 10.1021/acsami.6b13988] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Tetrabenzoporphyrin (BP) is a p-type organic semiconductor characterized by the large, rigid π-framework, excellent stability, and good photoabsorption capability. These characteristics make BP and its derivatives prominent active-layer components in organic electronic and optoelectronic devices. However, the control of the solid-state arrangement of BP frameworks, especially in solution-processed thin films, has not been intensively explored, and charge-carrier mobilities observed in BP-based materials have stayed relatively low as compared to those in the best organic molecular semiconductors. This work concentrates on engineering the solid-state packing of a BP derivative, 5,15-bis(triisopropylsilyl)ethynyltetrabenzoporphyrin (TIPS-BP), toward achieving efficient charge-carrier transport in its solution-processed thin films. The effort leads to the selective formation of a brickwork packing that has two dimensionally extended π-staking. The maximum field-effect hole mobility in the resulting films reaches 1.1 cm2 V-1 s-1, which is approximately 14 times higher than the record value for pristine free-base BP (0.070 cm2 V-1 s-1). This achievement is enabled mainly through the optimization of three factors; namely, deposition process, cast solvent, and self-assembled monolayer that constitutes the dielectric surface. On the other hand, polarized-light microscopy and grazing-incident wide-angle X-ray diffraction analyses show that there remains some room for improvement in the in-plane homogeneity of molecular alignment, suggesting even higher charge-carrier mobilities can be obtained upon further optimization. These results will provide a useful basis for the polymorph engineering and morphology optimization in solution-processed organic molecular semiconductors.
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Affiliation(s)
- Kohtaro Takahashi
- Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Bowen Shan
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China
| | - Xiaomin Xu
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China
| | - Shuaijun Yang
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China
| | - Tomoyuki Koganezawa
- Japan Synchrotron Radiation Research Institute (JASRI) , SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Daiki Kuzuhara
- Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Naoki Aratani
- Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Mitsuharu Suzuki
- Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Qian Miao
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China
| | - Hiroko Yamada
- Graduate School of Materials Science, Nara Institute of Science and Technology , 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
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69
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Inoue J, Tsutsui Y, Choi W, Kubota K, Sakurai T, Seki S. Rapid Evaluation of Electron Mobilities at Semiconductor-Insulator Interfaces in an Ambient Atmosphere by a Contactless Microwave-Based Technique. ACS OMEGA 2017; 2:164-170. [PMID: 31457218 PMCID: PMC6640973 DOI: 10.1021/acsomega.6b00428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 01/05/2017] [Indexed: 05/31/2023]
Abstract
Intrinsic mobility of electrons at the interfaces between crystalline organic semiconductors and insulating dielectric polymer films was rapidly evaluated in an ambient atmosphere by TRMC@Interfaces, a noncontact and nondestructive method based on dielectric loss spectroscopy of microwaves. By just preparing simple metal-insulator-semiconductor devices, local-scale motions of charge carriers injected into the interface by pulses of gate bias voltage were monitored through reflected microwave changes, resulting in the evaluation of local-scale charge carrier mobilities together with the value of trap density at the interface. The evaluated high electron mobilities of 12 cm2 V-1 s-1 for N,N'-bis(cyclohexyl)naphthalene-1,4,5,8-bis(dicarboximide) (DCy-NDI) and 15 cm2 V-1 s-1 for N,N'-dioctylperylene-1,4,5,8-bis(dicarboximide) (DC 8 -PDI) are the benchmarks for organic semiconducting materials that are comparable with the highest ones reported from the field-effect transistor devices. The present TRMC@Interfaces was found to serve as a rapid screening technique to examine the intrinsic performance of organic semiconducting materials as well as a useful tool enabling the precise discussion on the relationship among their local-scale charge carrier mobility, thin-film morphology, and packing structure.
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Affiliation(s)
- Junichi Inoue
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Yusuke Tsutsui
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Wookjin Choi
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Kai Kubota
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
- Todaiji
High School, 1375 Misasagi-cho, Nara 631-0803, Japan
| | - Tsuneaki Sakurai
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Shu Seki
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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70
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Cretenoud J, Özen B, Schmaltz T, Görl D, Fabrizio A, Corminboeuf C, Fadaei Tirani F, Scopelliti R, Frauenrath H. Synthesis and characterization of semiaromatic polyamides comprising benzofurobenzofuran repeating units. Polym Chem 2017. [DOI: 10.1039/c7py00129k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Extended π-conjugated segments such as benzofurobenzofuran can be included into polyamides with high glass transition temperatures.
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Affiliation(s)
- Julien Cretenoud
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Materials
- Laboratory of Macromolecular and Organic Materials
- 1015 Lausanne
- Switzerland
| | - Bilal Özen
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Materials
- Laboratory of Macromolecular and Organic Materials
- 1015 Lausanne
- Switzerland
| | - Thomas Schmaltz
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Materials
- Laboratory of Macromolecular and Organic Materials
- 1015 Lausanne
- Switzerland
| | - Daniel Görl
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Materials
- Laboratory of Macromolecular and Organic Materials
- 1015 Lausanne
- Switzerland
| | - Alberto Fabrizio
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Chemical Science and Engineering
- Laboratory for Computational Molecular Design
- Switzerland
| | - Clémence Corminboeuf
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Chemical Science and Engineering
- Laboratory for Computational Molecular Design
- Switzerland
| | - Farzaneh Fadaei Tirani
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Chemical Science and Engineering
- Switzerland
| | - Rosario Scopelliti
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Chemical Science and Engineering
- Switzerland
| | - Holger Frauenrath
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- Institute of Materials
- Laboratory of Macromolecular and Organic Materials
- 1015 Lausanne
- Switzerland
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71
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Sosorev AY. Role of intermolecular charge delocalization and its dimensionality in efficient band-like electron transport in crystalline 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane (F2-TCNQ). Phys Chem Chem Phys 2017; 19:25478-25486. [DOI: 10.1039/c7cp04357k] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theoretical investigation unravels the importance of multidimensional intermolecular charge delocalization for efficient band-like charge transport in small-molecule organic semiconductors.
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Affiliation(s)
- Andrey Yu. Sosorev
- Faculty of Physics and International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow 119991
- Russia
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72
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Diemer PJ, Hayes J, Welchman E, Hallani R, Pookpanratana SJ, Hacker CA, Richter CA, Anthony JE, Thonhauser T, Jurchescu OD. The influence of isomer purity on trap states and performance of organic thin-film transistors. ADVANCED FUNCTIONAL MATERIALS 2017; 3:1600294. [PMID: 29230154 PMCID: PMC5721359 DOI: 10.1002/aelm.201600294] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Organic field-effect transistor (OFET) performance is dictated by its composition and geometry, as well as the quality of the organic semiconductor (OSC) film, which strongly depends on purity and microstructure. When present, impurities and defects give rise to trap states in the bandgap of the OSC, lowering device performance. Here, 2,8-difluoro-5,11-bis(triethylsilylethynyl)-anthradithiophene is used as a model system to study the mechanism responsible for performance degradation in OFETs due to isomer coexistence. The density of trapping states is evaluated through temperature dependent current-voltage measurements, and it is discovered that OFETs containing a mixture of syn- and anti-isomers exhibit a discrete trapping state detected as a peak located at ~ 0.4 eV above the valence-band edge, which is absent in the samples fabricated on single-isomer films. Ultraviolet photoelectron spectroscopy measurements and density functional theory calculations do not point to a significant difference in electronic band structure between individual isomers. Instead, it is proposed that the dipole moment of the syn-isomer present in the host crystal of the anti-isomer locally polarizes the neighboring molecules, inducing energetic disorder. The isomers can be separated by applying gentle mechanical vibrations during film crystallization, as confirmed by the suppression of the peak and improvement in device performance.
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Affiliation(s)
- Peter J Diemer
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Jacori Hayes
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Evan Welchman
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Rawad Hallani
- Department of Chemistry, University of Kentucky, Lexington, KY 40506, USA
| | - Sujitra J Pookpanratana
- Engineering Physics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Christina A Hacker
- Engineering Physics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Curt A Richter
- Engineering Physics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - John E Anthony
- Department of Chemistry, University of Kentucky, Lexington, KY 40506, USA
| | - Timo Thonhauser
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Oana D Jurchescu
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
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73
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Brédas JL, Sargent EH, Scholes GD. Photovoltaic concepts inspired by coherence effects in photosynthetic systems. NATURE MATERIALS 2016; 16:35-44. [PMID: 27994245 DOI: 10.1038/nmat4767] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 09/05/2016] [Indexed: 05/20/2023]
Abstract
The past decade has seen rapid advances in our understanding of how coherent and vibronic phenomena in biological photosynthetic systems aid in the efficient transport of energy from light-harvesting antennas to photosynthetic reaction centres. Such coherence effects suggest strategies to increase transport lengths even in the presence of structural disorder. Here we explore how these principles could be exploited in making improved solar cells. We investigate in depth the case of organic materials, systems in which energy and charge transport stand to be improved by overcoming challenges that arise from the effects of static and dynamic disorder - structural and energetic - and from inherently strong electron-vibration couplings. We discuss how solar-cell device architectures can evolve to use coherence-exploiting materials, and we speculate as to the prospects for a coherent energy conversion system. We conclude with a survey of the impacts of coherence and bioinspiration on diverse solar-energy harvesting solutions, including artificial photosynthetic systems.
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Affiliation(s)
- Jean-Luc Brédas
- Division of Physical Science and Engineering, Solar and Photovoltaics Engineering Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Edward H Sargent
- Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario M5S 3G4, Canada
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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