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Xu Y, Yan J, Zhou W, Ouyang J. Development of High Performance Thermoelectric Polymers via Doping or Dedoping Engineering. Chem Asian J 2024; 19:e202400329. [PMID: 38736306 DOI: 10.1002/asia.202400329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/11/2024] [Accepted: 05/12/2024] [Indexed: 05/14/2024]
Abstract
It is of great significance to develop high-performance thermoelectric (TE) materials, because they can be used to harvest waste heat into electricity and there is abundant waste heat on earth. The conventional TE materials are inorganic semimetals or semiconductors like Bi2Te3 and its derivatives. However, they have problems of high cost, scarce/toxic elements, high thermal conductivity, and poor mechanical flexibility. Organic TE materials emerged as the next-generation TE materials because of their merits including solution processability, low cost, abundant element, low intrinsic thermal conductivity, and high mechanical flexibility. Organic TE materials are mainly conducting polymers because of their high conductivity. Both the conductivity and Seebeck coefficient depend on the doping level, and they are interdependent. Hence, the TE properties of polymers can be improved through doping/dedoping engineering. There are three types of doping forms, oxidative (or reductive) doping, protonic acid doping, and charge transfer doping. Accordingly, they can be dedoped by different approaches. In this article, we review the methods to dope and dedope p-type and n-type TE polymers and the combination of doping and dedoping to optimize their TE properties. Secondary doping is also covered, since it can significantly enhance the conductivity of some TE polymers.
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Affiliation(s)
- Yichen Xu
- National University of Singapore (Suzhou) Research Institute, No. 377 Linquan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117574, China
| | - Jin Yan
- National University of Singapore (Suzhou) Research Institute, No. 377 Linquan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China
| | - Wei Zhou
- National University of Singapore (Suzhou) Research Institute, No. 377 Linquan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China
| | - Jianyong Ouyang
- National University of Singapore (Suzhou) Research Institute, No. 377 Linquan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117574, China
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2
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Fan X, He S, Feng P, Xiao Y, Yin C, Du YA, Li M, Zhao L, Gao L. Realizing Ultrafast Response Speed for Self-Powered Photodetectors with a Molecular-Doped Lateral InSe Homojunction. J Phys Chem Lett 2024; 15:5923-5934. [PMID: 38809779 DOI: 10.1021/acs.jpclett.4c01158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
The implementation of energy-saving policies has stimulated intensive interest in exploring self-powered optoelectronic devices. The 2D p-n homojunction exhibits effective generation and separation of carriers excited by light, realizing lower power consumption and higher performance photodetectors. Here, a self-powered photodetector with high performance is fabricated based on an F4-TCNQ localized molecular-doped lateral InSe homojunction. Compared with the intrinsic InSe photodetector, the switching light ratio (Ilight/Idark) of the p-n homojunction device can be enhanced by 2.2 × 104, and the temporal response is also dramatically improved to 24/30 μs. Benefiting from the built-in electric field, due to the formation of an InSe p-n homojunction after partial doping of F4-TCNQ on InSe, the device possesses a high responsivity (R) of 93.21 mA/W, with a specific detectivity (D*) of 1.14 × 1011 Jones. These results suggest a promising approach to get a lateral InSe p-n homojunction and reveal the potential application of the device for next generation low-consumption photodetectors.
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Affiliation(s)
- Xiaofeng Fan
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Sixian He
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Pu Feng
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, School of Micro-Nano Electronics, Zhejiang University, Hangzhou 311215, China
| | - Yuke Xiao
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chengdong Yin
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yu-An Du
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ming Li
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liancheng Zhao
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liming Gao
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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3
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Craighero M, Guo J, Zokaei S, Griggs S, Tian J, Asatryan J, Kimpel J, Kroon R, Xu K, Reparaz JS, Martín J, McCulloch I, Campoy-Quiles M, Müller C. Impact of Oligoether Side-Chain Length on the Thermoelectric Properties of a Polar Polythiophene. ACS APPLIED ELECTRONIC MATERIALS 2024; 6:2909-2916. [PMID: 38828039 PMCID: PMC11137803 DOI: 10.1021/acsaelm.3c00936] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 08/31/2023] [Indexed: 06/05/2024]
Abstract
Conjugated polymers with oligoether side chains make up a promising class of thermoelectric materials. In this work, the impact of the side-chain length on the thermoelectric and mechanical properties of polythiophenes is investigated. Polymers with tri-, tetra-, or hexaethylene glycol side chains are compared, and the shortest length is found to result in thin films with the highest degree of order upon doping with the p-dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). As a result, a stiff material with an electrical conductivity of up to 830 ± 15 S cm-1 is obtained, resulting in a thermoelectric power factor of about 21 μW m-1 K-2 in the case of as-cast films. Aging at ambient conditions results in an initial decrease in thermoelectric properties but then yields a highly stable performance for at least 3 months, with values of about 200 S cm-1 and 5 μW m-1 K-2. Evidently, identification of the optimal side-chain length is an important criterion for the design of conjugated polymers for organic thermoelectrics.
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Affiliation(s)
- Mariavittoria Craighero
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Goteborg 41296, Sweden
| | - Jiali Guo
- Materials
Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Sepideh Zokaei
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Goteborg 41296, Sweden
| | - Sophie Griggs
- Department
of Chemistry, University of Oxford, Chemistry
Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Junfu Tian
- Department
of Chemistry, University of Oxford, Chemistry
Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Jesika Asatryan
- Universidade
da Coruña, Campus Industrial de Ferrol, CITENI, Esteiro, 15403 Ferrol, Spain
| | - Joost Kimpel
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Goteborg 41296, Sweden
| | - Renee Kroon
- Laboratory
of Organic Electronics, Linköping
University, 60174 Norrköping, Sweden
| | - Kai Xu
- Materials
Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Juan Sebastian Reparaz
- Materials
Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Jaime Martín
- Universidade
da Coruña, Campus Industrial de Ferrol, CITENI, Esteiro, 15403 Ferrol, Spain
- POLYMAT, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain
| | - Iain McCulloch
- Department
of Chemistry, University of Oxford, Chemistry
Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Mariano Campoy-Quiles
- Materials
Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Christian Müller
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Goteborg 41296, Sweden
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Le CV, Yoon H. Advances in the Use of Conducting Polymers for Healthcare Monitoring. Int J Mol Sci 2024; 25:1564. [PMID: 38338846 PMCID: PMC10855550 DOI: 10.3390/ijms25031564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/21/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
Conducting polymers (CPs) are an innovative class of materials recognized for their high flexibility and biocompatibility, making them an ideal choice for health monitoring applications that require flexibility. They are active in their design. Advances in fabrication technology allow the incorporation of CPs at various levels, by combining diverse CPs monomers with metal particles, 2D materials, carbon nanomaterials, and copolymers through the process of polymerization and mixing. This method produces materials with unique physicochemical properties and is highly customizable. In particular, the development of CPs with expanded surface area and high conductivity has significantly improved the performance of the sensors, providing high sensitivity and flexibility and expanding the range of available options. However, due to the morphological diversity of new materials and thus the variety of characteristics that can be synthesized by combining CPs and other types of functionalities, choosing the right combination for a sensor application is difficult but becomes important. This review focuses on classifying the role of CP and highlights recent advances in sensor design, especially in the field of healthcare monitoring. It also synthesizes the sensing mechanisms and evaluates the performance of CPs on electrochemical surfaces and in the sensor design. Furthermore, the applications that can be revolutionized by CPs will be discussed in detail.
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Affiliation(s)
- Cuong Van Le
- School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea;
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Hyeonseok Yoon
- School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea;
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
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5
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Nugraha MI, Indriyati I, Primadona I, Gedda M, Timuda GE, Iskandar F, Anthopoulos TD. Recent Progress in Colloidal Quantum Dot Thermoelectrics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2210683. [PMID: 36857683 DOI: 10.1002/adma.202210683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/12/2023] [Indexed: 06/18/2023]
Abstract
Semiconducting colloidal quantum dots (CQDs) represent an emerging class of thermoelectric materials for use in a wide range of future applications. CQDs combine solution processability at low temperatures with the potential for upscalable manufacturing via printing techniques. Moreover, due to their low dimensionality, CQDs exhibit quantum confinement and a high density of grain boundaries, which can be independently exploited to tune the Seebeck coefficient and thermal conductivity, respectively. This unique combination of attractive attributes makes CQDs very promising for application in emerging thermoelectric generator (TEG) technologies operating near room temperature. Herein, recent progress in CQDs for application in emerging thin-film thermoelectrics is reviewed. First, the fundamental concepts of thermoelectricity in nanostructured materials are outlined, followed by an overview of the popular synthetic methods used to produce CQDs with controllable sizes and shapes. Recent strides in CQD-based thermoelectrics are then discussed with emphasis on their application in thin-film TEGs. Finally, the current challenges and future perspectives for further enhancing the performance of CQD-based thermoelectric materials for future applications are discussed.
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Affiliation(s)
- Mohamad Insan Nugraha
- Physical Science and Engineering Division (PSE), KAUST Solar Center (KSC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), South Tangerang, Banten, 15314, Indonesia
| | - Indriyati Indriyati
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), South Tangerang, Banten, 15314, Indonesia
- Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia
| | - Indah Primadona
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), South Tangerang, Banten, 15314, Indonesia
- Collaboration Research Center for Advanced Energy Materials, National Research and Innovation Agency - Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40135, Indonesia
| | - Murali Gedda
- Physical Science and Engineering Division (PSE), KAUST Solar Center (KSC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Gerald Ensang Timuda
- Research Center for Advanced Materials, National Research and Innovation Agency (BRIN), South Tangerang, Banten, 15314, Indonesia
| | - Ferry Iskandar
- Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia
- Collaboration Research Center for Advanced Energy Materials, National Research and Innovation Agency - Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40135, Indonesia
| | - Thomas D Anthopoulos
- Physical Science and Engineering Division (PSE), KAUST Solar Center (KSC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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6
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Shen Z, Lu W, Wei P, Zhu Y, Jiang Y, Bu L, Lu G. Highly Conductive Ultrathin Layers of Conjugated Polymers for Metal-Free Coplanar Transistors with Single-Polymer Transport Layers. ACS APPLIED MATERIALS & INTERFACES 2023; 15:12099-12108. [PMID: 36808932 DOI: 10.1021/acsami.2c20298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Although metal or oxide conductive films are widely used as electrodes of electronic devices, organic electrodes would be more favorable for next-generation organic electronics. Here, using some model conjugated polymers as examples, we report a class of highly conductive and optically transparent polymer ultrathin layers. Vertical phase separation of semiconductor/insulator blends leads to a highly ordered two-dimensional (2D) ultrathin layer of conjugated-polymer chains on the insulator. Afterwards, the thermally evaporated dopants on the ultrathin layer lead to a conductivity of up to 103 S cm-1 and a sheet resistance 103 Ω/square for a model conjugated polymer poly(2,5-bis(3-hexadecylthiophen-2-yl)thieno[3,2-b]thiophenes) (PBTTT). The high conductivity is due to the high hole mobility (∼ 20 cm2 V-1 s-1), although doping-induced charge density is still in the moderate range of 1020 cm-3 with a 1 nm thick dopant. Metal-free monolithic coplanar field-effect transistors using the same conjugated-polymer ultrathin layer with alternatively doped regions as electrodes and a semiconductor layer are realized. The field-effect mobility of this monolithic transistor is over 2 cm2 V-1 s-1 for PBTTT, one order higher than that of the conventional PBTTT transistor using metal electrodes. The optical transparency of the single conjugated-polymer transport layer is over 90%, demonstrating a bright future for all-organic transparent electronics.
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Affiliation(s)
- Zichao Shen
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
| | - Wanlong Lu
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
| | - Peng Wei
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yuanwei Zhu
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yihang Jiang
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
| | - Laju Bu
- School of Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Guanghao Lu
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China
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7
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Mu X, Wang W, Sun C, Zhao D, Ma C, Zhu J, Knez M. Greatly increased electrical conductivity of PBTTT-C14 thin film via controllable single precursor vapor phase infiltration. NANOTECHNOLOGY 2022; 34:015709. [PMID: 36191569 DOI: 10.1088/1361-6528/ac96fa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Doping is an important strategy for effectively regulating the charge carrier concentration of semiconducting materials. In this study, the electronic properties of organic-inorganic hybrid semiconducting polymers, synthesized viain situcontrolled vapor phase infiltration (VPI) of poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT-C14) with the metal precursors molybdenum pentachloride (MoCl5) and titanium tetrachloride (TiCl4), were altered and characterized. The conductivities of the infiltration-doped PBTTT-C14 thin films were enhanced by up to 9 and 4 orders of magnitude, respectively. The significantly improved electrical properties may result from interactions between metal atoms in the metal precursors and sulfur of the thiophene rings, thus forming new chemical bonds. Importantly, VPI doping has little influence on the structure of the PBTTT-C14 thin films. Even if various dopant molecules infiltrate the polymer matrix, the interlayer spacing of the films will inevitably expand, but it has negligible effects on the overall morphology and structure of the film. Also, Lewis acid-doped PBTTT-C14 thin films exhibited excellent environmental stability. Therefore, the VPI-based doping process has great potential for use in processing high-quality conductive polymer films.
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Affiliation(s)
- Xueyang Mu
- School of Materials Science and Engineering, Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, Shaanxi University of Science & Technology Xi'an, Shaanxi 710021, People's Republic of China
| | - Weike Wang
- School of Materials Science and Engineering, Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, Shaanxi University of Science & Technology Xi'an, Shaanxi 710021, People's Republic of China
| | - Chongcai Sun
- School of Materials Science and Engineering, Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, Shaanxi University of Science & Technology Xi'an, Shaanxi 710021, People's Republic of China
| | - Dan Zhao
- School of Materials Science and Engineering, Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, Shaanxi University of Science & Technology Xi'an, Shaanxi 710021, People's Republic of China
| | - Chuang Ma
- School of Materials Science and Engineering, Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, Shaanxi University of Science & Technology Xi'an, Shaanxi 710021, People's Republic of China
| | - Jiankang Zhu
- Guangzhou Special Pressure Equipment Inspection and Research Institute, National Graphene Product Quality Supervision and Inspection Center, Guangzhou, Guangdong 510700, People's Republic of China
| | - Mato Knez
- CIC nanoGUNE, Tolosa Hiribidea, 76, Donostia-San Sebastián, E-20018, Spain
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8
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Influence of Solvent-Dependent Morphology on Molecular Doping and Charge Transport in Conductive Thiophene Polymer. MATERIALS 2022; 15:ma15093293. [PMID: 35591627 PMCID: PMC9105990 DOI: 10.3390/ma15093293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 04/22/2022] [Accepted: 05/01/2022] [Indexed: 02/01/2023]
Abstract
The utility of a solvent is one of the key factors that impacts resultant film morphology. However, the effect of solvent-dependent morphology on the doping process and electrical conductivity has not been adequately elucidated. In this work, we compared the morphology of chloroform- and chlorobenzene-processed thiophene polymer films and investigated how the choice of solvent influences film morphology, doping level, charge transport properties, and thus electrical conductivity. It was found that the film drop-casted from chloroform exhibits better crystallinity than that drop-casted from chlorobenzene. The crystallinity has negligible impact on the doping level but significant impact on charge transport properties. As a result, the chloroform-processed film shows a higher electrical conductivity of up to 408 S cm-1 due to a high carrier mobility related to the continuously crystalline domains in film. This finding indicates that the choice of solvent for preparation of film, which strongly correlated with molecular orientation, is a new strategy to optimize the electrical conductivity of doped polymers.
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9
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Scaccabarozzi AD, Basu A, Aniés F, Liu J, Zapata-Arteaga O, Warren R, Firdaus Y, Nugraha MI, Lin Y, Campoy-Quiles M, Koch N, Müller C, Tsetseris L, Heeney M, Anthopoulos TD. Doping Approaches for Organic Semiconductors. Chem Rev 2021; 122:4420-4492. [PMID: 34793134 DOI: 10.1021/acs.chemrev.1c00581] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Electronic doping in organic materials has remained an elusive concept for several decades. It drew considerable attention in the early days in the quest for organic materials with high electrical conductivity, paving the way for the pioneering work on pristine organic semiconductors (OSCs) and their eventual use in a plethora of applications. Despite this early trend, however, recent strides in the field of organic electronics have been made hand in hand with the development and use of dopants to the point that are now ubiquitous. Here, we give an overview of all important advances in the area of doping of organic semiconductors and their applications. We first review the relevant literature with particular focus on the physical processes involved, discussing established mechanisms but also newly proposed theories. We then continue with a comprehensive summary of the most widely studied dopants to date, placing particular emphasis on the chemical strategies toward the synthesis of molecules with improved functionality. The processing routes toward doped organic films and the important doping-processing-nanostructure relationships, are also discussed. We conclude the review by highlighting how doping can enhance the operating characteristics of various organic devices.
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Affiliation(s)
- Alberto D Scaccabarozzi
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia
| | - Aniruddha Basu
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia
| | - Filip Aniés
- Department of Chemistry and Centre for Processable Electronics, Imperial College London, London W12 0BZ, U.K
| | - Jian Liu
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg 412 96, Sweden
| | - Osnat Zapata-Arteaga
- Materials Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Ross Warren
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Yuliar Firdaus
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia.,Research Center for Electronics and Telecommunication, Indonesian Institute of Science, Jalan Sangkuriang Komplek LIPI Building 20 level 4, Bandung 40135, Indonesia
| | - Mohamad Insan Nugraha
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia
| | - Yuanbao Lin
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia
| | - Mariano Campoy-Quiles
- Materials Science Institute of Barcelona, ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Spain
| | - Norbert Koch
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Kekulé-Strasse 5, 12489 Berlin, Germany.,Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Christian Müller
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg 412 96, Sweden
| | - Leonidas Tsetseris
- Department of Physics, National Technical University of Athens, Athens GR-15780, Greece
| | - Martin Heeney
- Department of Chemistry and Centre for Processable Electronics, Imperial College London, London W12 0BZ, U.K
| | - Thomas D Anthopoulos
- King Abdullah University of Science and Technology (KAUST), KAUST Solar Center (KSC), Thuwal 23955, Saudi Arabia
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10
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Massetti M, Jiao F, Ferguson AJ, Zhao D, Wijeratne K, Würger A, Blackburn JL, Crispin X, Fabiano S. Unconventional Thermoelectric Materials for Energy Harvesting and Sensing Applications. Chem Rev 2021; 121:12465-12547. [PMID: 34702037 DOI: 10.1021/acs.chemrev.1c00218] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Heat is an abundant but often wasted source of energy. Thus, harvesting just a portion of this tremendous amount of energy holds significant promise for a more sustainable society. While traditional solid-state inorganic semiconductors have dominated the research stage on thermal-to-electrical energy conversion, carbon-based semiconductors have recently attracted a great deal of attention as potential thermoelectric materials for low-temperature energy harvesting, primarily driven by the high abundance of their atomic elements, ease of processing/manufacturing, and intrinsically low thermal conductivity. This quest for new materials has resulted in the discovery of several new kinds of thermoelectric materials and concepts capable of converting a heat flux into an electrical current by means of various types of particles transporting the electric charge: (i) electrons, (ii) ions, and (iii) redox molecules. This has contributed to expanding the applications envisaged for thermoelectric materials far beyond simple conversion of heat into electricity. This is the motivation behind this review. This work is divided in three sections. In the first section, we present the basic principle of the thermoelectric effects when the particles transporting the electric charge are electrons, ions, and redox molecules and describe the conceptual differences between the three thermodiffusion phenomena. In the second section, we review the efforts made on developing devices exploiting these three effects and give a thorough understanding of what limits their performance. In the third section, we review the state-of-the-art thermoelectric materials investigated so far and provide a comprehensive understanding of what limits charge and energy transport in each of these classes of materials.
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Affiliation(s)
- Matteo Massetti
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden
| | - Fei Jiao
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden.,Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Sciences, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Andrew J Ferguson
- National Renewable Energy Laboratory, Golden, Colorado, 80401 United States
| | - Dan Zhao
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden
| | - Kosala Wijeratne
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden
| | - Alois Würger
- Laboratoire Ondes et Matière d'Aquitaine, Université de Bordeaux, 351 cours de la Libération, F-33405 Talence Cedex, France
| | | | - Xavier Crispin
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden
| | - Simone Fabiano
- Department of Science and Technology, Linköping University, SE-60174 Norrköping, Sweden
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11
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Untilova V, Zeng H, Durand P, Herrmann L, Leclerc N, Brinkmann M. Intercalation and Ordering of F 6TCNNQ and F 4TCNQ Dopants in Regioregular Poly(3-hexylthiophene) Crystals: Impact on Anisotropic Thermoelectric Properties of Oriented Thin Films. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00554] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Huiyan Zeng
- Université de Strasbourg, CNRS, ICS UPR 22, F-67000 Strasbourg, France
| | - Pablo Durand
- Université de Strasbourg, CNRS, ICPEES UMR 7515, F-67087 Strasbourg, France
| | - Laurent Herrmann
- Université de Strasbourg, CNRS, ICS UPR 22, F-67000 Strasbourg, France
| | - Nicolas Leclerc
- Université de Strasbourg, CNRS, ICPEES UMR 7515, F-67087 Strasbourg, France
| | - Martin Brinkmann
- Université de Strasbourg, CNRS, ICS UPR 22, F-67000 Strasbourg, France
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12
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Mardi S, Yusupov K, Martinez PM, Zakhidov A, Vomiero A, Reale A. Enhanced Thermoelectric Properties of Poly(3-hexylthiophene) through the Incorporation of Aligned Carbon Nanotube Forest and Chemical Treatments. ACS OMEGA 2021; 6:1073-1082. [PMID: 33490766 PMCID: PMC7818073 DOI: 10.1021/acsomega.0c02663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 09/04/2020] [Indexed: 06/12/2023]
Abstract
Carbon nanotube/polymer composites have recently received considerable attention for thermoelectric (TE) applications. The TE power factor can be significantly improved by forming composites with carbon nanotubes. However, the formation of a uniform and well-ordered nanocomposite film is still challenging because of the creation of agglomerates and the uneven distribution of nanotubes. Here, we developed a facile, efficient, and easy-processable route to produce uniform and aligned nanocomposite films of P3HT and carbon nanotube forest (CNTF). The electrical conductivity of a pristine P3HT film was improved from ∼10-7 to 160 S/cm thanks to the presence of CNTF. Also, a further boost in TE performance was achieved using two additives, lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) and tert-butylpyridine. By adding the additives to P3HT, the degree of interchain order increased, which facilitated the charge transport through the composite. Under the optimal conditions, the incorporation of CNTF and additives led to values of the Seebeck coefficient, electrical conductivity, and power factor up to rising 92 μV/K, 130 S/cm, and 110 μW/m K2, respectively, at a temperature of 344.15 K. The excellent TE performance of the hybrid films originates from the dramatically increased electrical conductivity and the improved Seebeck coefficient by CNTF and additives, respectively.
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Affiliation(s)
- Saeed Mardi
- Department
of Electronic Engineering, CHOSE-Centre for Hybrid and Organic Solar
Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy
| | - Khabib Yusupov
- Division
of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, 97187 LuleÅ, Sweden
| | - Patricia M. Martinez
- NanoTech
Institute, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Anvar Zakhidov
- NanoTech
Institute, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Alberto Vomiero
- Division
of Materials Science, Department of Engineering Sciences and Mathematics, Luleå University of Technology, 97187 LuleÅ, Sweden
- Department
of Molecular Sciences and Nanosystems, Ca’
Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy
| | - Andrea Reale
- Department
of Electronic Engineering, CHOSE-Centre for Hybrid and Organic Solar
Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy
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13
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Voss MG, Challa JR, Scholes DT, Yee PY, Wu EC, Liu X, Park SJ, León Ruiz O, Subramaniyan S, Chen M, Jenekhe SA, Wang X, Tolbert SH, Schwartz BJ. Driving Force and Optical Signatures of Bipolaron Formation in Chemically Doped Conjugated Polymers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2000228. [PMID: 33296113 DOI: 10.1002/adma.202000228] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 10/11/2020] [Indexed: 06/12/2023]
Abstract
Molecular dopants are often added to semiconducting polymers to improve electrical conductivity. However, the use of such dopants does not always produce mobile charge carriers. In this work, ultrafast spectroscopy is used to explore the nature of the carriers created following doping of conjugated push-pull polymers with both F4 TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane) and FeCl3 . It is shown that for one particular push-pull material, the charge carriers created by doping are entirely non-conductive bipolarons and not single polarons, and that transient absorption spectroscopy following excitation in the infrared can readily distinguish the two types of charge carriers. Based on density functional theory calculations and experiments on multiple push-pull conjugated polymers, it is argued that the size of the donor push units determines the relative stabilities of polarons and bipolarons, with larger donor units stabilizing the bipolarons by providing more area for two charges to co-reside.
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Affiliation(s)
- Matthew G Voss
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - J Reddy Challa
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - D Tyler Scholes
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Patrick Y Yee
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Eric C Wu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Xiao Liu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Sanghyun J Park
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Omar León Ruiz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Selvam Subramaniyan
- Department of Chemical Engineering and Department of Chemistry, University of Washington, Seattle, WA, 98195-1750, USA
| | - Mengdan Chen
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Samson A Jenekhe
- Department of Chemical Engineering and Department of Chemistry, University of Washington, Seattle, WA, 98195-1750, USA
| | - Xiaolin Wang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Sarah H Tolbert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-8352, USA
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095-1595, USA
| | - Benjamin J Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-8352, USA
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14
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Watts KE, Neelamraju B, Moser M, McCulloch I, Ratcliff EL, Pemberton JE. Thermally Induced Formation of HF 4TCNQ - in F 4TCNQ-Doped Regioregular P3HT. J Phys Chem Lett 2020; 11:6586-6592. [PMID: 32701299 DOI: 10.1021/acs.jpclett.0c01673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The prototypical system for understanding doping in solution-processed organic electronics has been poly(3-hexylthiophene) (P3HT) p-doped with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). Multiple charge-transfer states, defined by the fraction of electron transfer to F4TCNQ, are known to coexist and are dependent on polymer molecular weight, crystallinity, and processing. Less well-understood is the loss of conductivity after thermal annealing of these materials. Specifically, in thermoelectrics, F4TCNQ-doped regioregular (rr) P3HT exhibits significant conductivity losses at temperatures lower than other thiophene-based polymers. Through detailed spectroscopic investigation of progressively heated P3HT films coprocessed with F4TCNQ, we demonstrate that this diminished conductivity is due to formation of the nonchromophoric, weak dopant HF4TCNQ-. This species is likely formed through hydrogen abstraction from the α aliphatic carbon of the hexyl chain at the 3-position of thiophene rings of rr-P3HT. This reaction is eliminated for polymers with ethylene glycol-containing side chains, which retain conductivity at higher operating temperatures. In total, these results provide a critical materials design guideline for organic electronics.
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Affiliation(s)
| | | | - Maximilian Moser
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, London, U.K
| | - Iain McCulloch
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, London, U.K
- KSC, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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15
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Untilova V, Hynynen J, Hofmann AI, Scheunemann D, Zhang Y, Barlow S, Kemerink M, Marder SR, Biniek L, Müller C, Brinkmann M. High Thermoelectric Power Factor of Poly(3-hexylthiophene) through In-Plane Alignment and Doping with a Molybdenum Dithiolene Complex. Macromolecules 2020; 53:6314-6321. [PMID: 32913375 PMCID: PMC7472519 DOI: 10.1021/acs.macromol.0c01223] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/22/2020] [Indexed: 12/27/2022]
Abstract
We report a record thermoelectric power factor of up to 160 μW m-1 K-2 for the conjugated polymer poly(3-hexylthiophene) (P3HT). This result is achieved through the combination of high-temperature rubbing of thin films together with the use of a large molybdenum dithiolene p-dopant with a high electron affinity. Comparison of the UV-vis-NIR spectra of the chemically doped samples to electrochemically oxidized material reveals an oxidation level of 10%, i.e., one polaron for every 10 repeat units. The high power factor arises due to an increase in the charge-carrier mobility and hence electrical conductivity along the rubbing direction. We conclude that P3HT, with its facile synthesis and outstanding processability, should not be ruled out as a potential thermoelectric material.
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Affiliation(s)
| | - Jonna Hynynen
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, 41296 Göteborg, Sweden
| | - Anna I. Hofmann
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, 41296 Göteborg, Sweden
| | - Dorothea Scheunemann
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, 41296 Göteborg, Sweden
| | - Yadong Zhang
- School
of Chemistry & Biochemistry and Center for Organic Photonics and
Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Stephen Barlow
- School
of Chemistry & Biochemistry and Center for Organic Photonics and
Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Martijn Kemerink
- Centre
for Advanced Materials, Heidelberg University, 69120 Heidelberg, Germany
| | - Seth R. Marder
- School
of Chemistry & Biochemistry and Center for Organic Photonics and
Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Laure Biniek
- CNRS,
ICS UPR 22, Université de Strasbourg, F-67000 Strasbourg, France
| | - Christian Müller
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, 41296 Göteborg, Sweden
| | - Martin Brinkmann
- CNRS,
ICS UPR 22, Université de Strasbourg, F-67000 Strasbourg, France
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16
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Untilova V, Biskup T, Biniek L, Vijayakumar V, Brinkmann M. Control of Chain Alignment and Crystallization Helps Enhance Charge Conductivities and Thermoelectric Power Factors in Sequentially Doped P3HT:F4TCNQ Films. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b02389] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
| | - Till Biskup
- Physikalische Chemie und Didaktik der Chemie, Universität des Saarlandes, Campus B2 2, 66123 Saarbrücken, Germany
| | - Laure Biniek
- Université de Strasbourg, CNRS, ICS UPR 22, F-67000 Strasbourg, France
| | | | - Martin Brinkmann
- Université de Strasbourg, CNRS, ICS UPR 22, F-67000 Strasbourg, France
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17
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Mardi S, Pea M, Notargiacomo A, Yaghoobi Nia N, Carlo AD, Reale A. The Molecular Weight Dependence of Thermoelectric Properties of Poly (3-Hexylthiophene). MATERIALS (BASEL, SWITZERLAND) 2020; 13:E1404. [PMID: 32204569 PMCID: PMC7142503 DOI: 10.3390/ma13061404] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 03/12/2020] [Accepted: 03/16/2020] [Indexed: 11/17/2022]
Abstract
Organic materials have been found to be promising candidates for low-temperature thermoelectric applications. In particular, poly (3-hexylthiophene) (P3HT) has been attracting great interest due to its desirable intrinsic properties, such as excellent solution processability, chemical and thermal stability, and high field-effect mobility. However, its poor electrical conductivity has limited its application as a thermoelectric material. It is therefore important to improve the electrical conductivity of P3HT layers. In this work, we studied how molecular weight (MW) influences the thermoelectric properties of P3HT films. The films were doped with lithium bis(trifluoromethane sulfonyl) imide salt (LiTFSI) and 4-tert butylpyridine (TBP). Various P3HT layers with different MWs ranging from 21 to 94 kDa were investigated. UV-Vis spectroscopy and atomic force microscopy (AFM) analysis were performed to investigate the morphology and structure features of thin films with different MWs. The electrical conductivity initially increased when the MW increased and then decreased at the highest MW, whereas the Seebeck coefficient had a trend of reducing as the MW grew. The maximum thermoelectric power factor (1.87 μW/mK2) was obtained for MW of 77 kDa at 333 K. At this temperature, the electrical conductivity and Seebeck coefficient of this MW were 65.5 S/m and 169 μV/K, respectively.
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Affiliation(s)
- Saeed Mardi
- Department of Electronic Engineering, CHOSE—Centre for Hybrid and Organic Solar Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy; (S.M.); (N.Y.N.); (A.D.C.)
| | - Marialilia Pea
- Institute for Photonics and Nanotechnologies, CNR, 00156 Rome, Italy; (M.P.); (A.N.)
| | - Andrea Notargiacomo
- Institute for Photonics and Nanotechnologies, CNR, 00156 Rome, Italy; (M.P.); (A.N.)
| | - Narges Yaghoobi Nia
- Department of Electronic Engineering, CHOSE—Centre for Hybrid and Organic Solar Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy; (S.M.); (N.Y.N.); (A.D.C.)
| | - Aldo Di Carlo
- Department of Electronic Engineering, CHOSE—Centre for Hybrid and Organic Solar Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy; (S.M.); (N.Y.N.); (A.D.C.)
| | - Andrea Reale
- Department of Electronic Engineering, CHOSE—Centre for Hybrid and Organic Solar Energy, University of Rome Tor Vergata, via del Politecnico 1, 00133 Rome, Italy; (S.M.); (N.Y.N.); (A.D.C.)
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18
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Yoon SE, Kang Y, Noh SY, Park J, Lee SY, Park J, Lee DW, Whang DR, Kim T, Kim GH, Seo H, Kim BG, Kim JH. High Efficiency Doping of Conjugated Polymer for Investigation of Intercorrelation of Thermoelectric Effects with Electrical and Morphological Properties. ACS APPLIED MATERIALS & INTERFACES 2020; 12:1151-1158. [PMID: 31808674 DOI: 10.1021/acsami.9b17825] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Intercorrelation of thermoelectric properties of a doped conjugated semiconducting polymer (PIDF-BT) with charge carrier density, conductive morphology, and crystallinity are systematically investigated. Upon being doped with F4-TCNQ by the sequential doping method, PIDF-BT exhibited a high electrical conductivity over 210 S cm-1. The significant enhancement of electrical conductivity resulted from a high charge carrier density, which is attributed to the effective charge-transfer-based integer doping between PIDF-BT and dopant molecules. Based on the systemic characterization on the optical, electrical, and structural properties of doped PIDF-BT annealed at different temperatures, we investigated the characteristic correlations between thermoelectric properties of PIDF-BT films and their four-probe electrical conductivity, charge carrier density, and charge carrier mobility obtained from AC Hall effect measurements. This study revealed that exercising fine control over the crystallinity and conductive migration of the conjugated polymer films can be a strategic approach to suppressing the degradation of the Seebeck coefficient at high charge carrier density and ultimately to maximizing the power factors of organic thermoelectric devices.
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Affiliation(s)
| | - Yeongkwon Kang
- Division of Chemical Engineering , Konkuk University , Seoul 05029 , Republic of Korea
| | - So Yeon Noh
- School of Mechanical, Aerospace and Nuclear Engineering , UNIST , Ulsan 44919 , Republic of Korea
| | - Jeongwoo Park
- Department of Physics , Hankuk University of Foreign Studies , Yongin 17035 , Republic of Korea
| | | | - Jaehong Park
- Division of Chemical Engineering , Konkuk University , Seoul 05029 , Republic of Korea
| | | | - Dong Ryeol Whang
- Linz Institute for Organic Solar Cells (LIOS)/Institute of Physical Chemistry , Johannes Kepler University Linz , 4040 Linz , Austria
| | - Taekyeong Kim
- Department of Physics , Hankuk University of Foreign Studies , Yongin 17035 , Republic of Korea
| | - Gun-Ho Kim
- School of Mechanical, Aerospace and Nuclear Engineering , UNIST , Ulsan 44919 , Republic of Korea
| | | | - Bong-Gi Kim
- Division of Chemical Engineering , Konkuk University , Seoul 05029 , Republic of Korea
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19
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Yee PY, Scholes DT, Schwartz BJ, Tolbert SH. Dopant-Induced Ordering of Amorphous Regions in Regiorandom P3HT. J Phys Chem Lett 2019; 10:4929-4934. [PMID: 31382748 DOI: 10.1021/acs.jpclett.9b02070] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Despite the fact that molecular doping of semiconducting polymers has emerged as a valuable strategy for improving the performance of organic electronic devices, the fundamental dopant-polymer interactions are not fully understood. Here we use 2-D grazing incidence wide-angle X-ray scattering (GIWAXS) to demonstrate that adding oxidizing small-molecule dopants, such as 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) and FeCl3, into the amorphous conjugated polymer, regiorandom poly(3-hexylthiophene-2,5-diyl) (RRa-P3HT), improves polymer ordering and induces a change in domain orientation from isotropic to mostly edge-on. Doping thus causes RRa-P3HT to behave similarly to the more ordered regioregular P3HT. By comparing the optical, electrical, and structural properties of RRa-P3HT films doped with F4TNCQ and FeCl3 and those infiltrated with 7,7,8,8-tetracyanoquinodimethane (TCNQ), which occupies a similar volume as F4TCNQ but does not dope RRa-P3HT, we show that the increased ordering results not from the ability of the dopant to fill space but instead from the need to delocalize charge on the polymer in more than one dimension.
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Affiliation(s)
- Patrick Y Yee
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - D Tyler Scholes
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Benjamin J Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
| | - Sarah H Tolbert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1569, United States
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, California 90095-1595, United States
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20
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Goel M, Heinrich CD, Krauss G, Thelakkat M. Principles of Structural Design of Conjugated Polymers Showing Excellent Charge Transport toward Thermoelectrics and Bioelectronics Applications. Macromol Rapid Commun 2019; 40:e1800915. [DOI: 10.1002/marc.201800915] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 02/21/2019] [Indexed: 01/01/2023]
Affiliation(s)
- Mahima Goel
- Applied Functional PolymersMacromolecular Chemistry IUniversity of Bayreuth Universitätsstr. 30 Bayreuth 95440 Germany
| | - C. David Heinrich
- Applied Functional PolymersMacromolecular Chemistry IUniversity of Bayreuth Universitätsstr. 30 Bayreuth 95440 Germany
| | - Gert Krauss
- Applied Functional PolymersMacromolecular Chemistry IUniversity of Bayreuth Universitätsstr. 30 Bayreuth 95440 Germany
| | - Mukundan Thelakkat
- Applied Functional PolymersMacromolecular Chemistry IUniversity of Bayreuth Universitätsstr. 30 Bayreuth 95440 Germany
- Bavarian Polymer Institute (BPI)University of Bayreuth Universitätsstr. 30 Bayreuth 95440 Germany
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21
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Aubry TJ, Axtell JC, Basile VM, Winchell KJ, Lindemuth JR, Porter TM, Liu JY, Alexandrova AN, Kubiak CP, Tolbert SH, Spokoyny AM, Schwartz BJ. Dodecaborane-Based Dopants Designed to Shield Anion Electrostatics Lead to Increased Carrier Mobility in a Doped Conjugated Polymer. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805647. [PMID: 30672037 DOI: 10.1002/adma.201805647] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/07/2018] [Indexed: 06/09/2023]
Abstract
One of the most effective ways to tune the electronic properties of conjugated polymers is to dope them with small-molecule oxidizing agents, creating holes on the polymer and molecular anions. Undesirably, strong electrostatic attraction from the anions of most dopants localizes the holes created on the polymer, reducing their mobility. Here, a new strategy utilizing a substituted boron cluster as a molecular dopant for conjugated polymers is employed. By designing the cluster to have a high redox potential and steric protection of the core-localized electron density, highly delocalized polarons with mobilities equivalent to films doped with no anions present are obtained. AC Hall effect measurements show that P3HT films doped with these boron clusters have conductivities and polaron mobilities roughly an order of magnitude higher than films doped with F4 TCNQ, even though the boron-cluster-doped films have poor crystallinity. Moreover, the number of free carriers approximately matches the number of boron clusters, yielding a doping efficiency of ≈100%. These results suggest that shielding the polaron from the anion is a critically important aspect for producing high carrier mobility, and that the high polymer crystallinity required with dopants such as F4 TCNQ is primarily to keep the counterions far from the polymer backbone.
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Affiliation(s)
- Taylor J Aubry
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Jonathan C Axtell
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Victoria M Basile
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - K J Winchell
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | | | - Tyler M Porter
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Ji-Yuan Liu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- Key Laboratory for Advanced Materials, Center for Computational Chemistry and Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Clifford P Kubiak
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Sarah H Tolbert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Alexander M Spokoyny
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
| | - Benjamin J Schwartz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, 90095-1569, USA
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22
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Vijayakumar V, Zaborova E, Biniek L, Zeng H, Herrmann L, Carvalho A, Boyron O, Leclerc N, Brinkmann M. Effect of Alkyl Side Chain Length on Doping Kinetics, Thermopower, and Charge Transport Properties in Highly Oriented F 4TCNQ-Doped PBTTT Films. ACS APPLIED MATERIALS & INTERFACES 2019; 11:4942-4953. [PMID: 30644706 DOI: 10.1021/acsami.8b17594] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Doping of polymer semiconductors such as poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2- b]thiophene) (PBTTT) with acceptor molecules such as 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) is widely used to tune the charge transport and thermoelectric (TE) properties in thin films. However, the mechanism of dopant insertion in the polymer matrix, insertion kinetics, and the ultimate doping levels reached have been investigated only marginally. This contribution addresses the effect of alkyl side chain length on the doping mechanism of a series of PBTTTs with linear side chains ranging from n-octyl to n-octyldecyl. The study focuses on thin films oriented by high-temperature rubbing and sequentially doped in F4TCNQ solution. Structure-property correlations are established as a function of side chain length by a combination of transmission electron microscopy, polarized UV-vis-NIR spectroscopy, and charge transport/thermopower measurements. Intercalation of F4TCNQ into the layers of side chains results in the expansion of the lattice along the side chains and the contraction along the π-stacking direction for all polymers. The extent of lattice expansion decreases with the increasing side chain length. UV-vis-NIR spectroscopy demonstrates integer charge transfer for all investigated PBTTTs. The doping kinetics and the final doping level depend on both the side chain length and packing. Highly disordered n-octyl and crystalline n-octyldecyl side chain layers tend to hamper dopant diffusion in the side chain layers contrary to n-dodecyl side chains that can host the highest proportion of dopants. Consequently, the best TE properties are observed for C12-PBTTT films. Alignment of the polymers significantly enhances the TE performance by increasing the charge conductivity and the thermopower along the rubbing direction. Aligned films of C12-PBTTT show charge conductivities of 193 S cm-1 along the rubbing direction and power factors of approximately 100 μW m-1 K-2 versus a few μW m-1 K-2 for nonoriented films.
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Affiliation(s)
- Vishnu Vijayakumar
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
| | - Elena Zaborova
- CiNaM, UMR 7325, Université Aix Marseille , Campus de Luminy, Case 913 , 13288 Marseille Cedex 9, France
- Université de Strasbourg, CNRS, ICPEES UMR 7515 , F-67087 Strasbourg , France
| | - Laure Biniek
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
| | - Huiyan Zeng
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
| | - Laurent Herrmann
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
| | - Alain Carvalho
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
| | - Olivier Boyron
- Laboratoire de Chimie Catalyse Polymères et Procédés (C2P2) , Université de Lyon 1, CPE Lyon, CNRS UMR 5265 , Bat 308F, 43 bd du 11 Novembre 1918 , 69616 Villeurbanne , France
| | - Nicolas Leclerc
- Université de Strasbourg, CNRS, ICPEES UMR 7515 , F-67087 Strasbourg , France
| | - Martin Brinkmann
- Université de Strasbourg, CNRS, ICS UPR 22 , F-67000 Strasbourg , France
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Karpov Y, Kiriy N, Formanek P, Zessin J, Hambsch M, Mannsfeld SCB, Lissel F, Beryozkina T, Bakulev V, Voit B, Kiriy A. Layer-by-Layer Assembly Enabled by the Anionic p-Dopant CN6-CP •-K +: a Route to Achieve Interfacial Doping of Organic Semiconductors. ACS APPLIED MATERIALS & INTERFACES 2019; 11:4159-4168. [PMID: 30608639 DOI: 10.1021/acsami.8b15033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Highly efficient 2D (interfacial) doping of organic semiconductors, poly(3-hexylthiophene) (P3HT) and TIPS-pentacene, was achieved by a polyelectrolyte-supported layer-by-layer assembly of the dual-mode functional dopant CN6-CP•-K+, having an anionic group for its fixation onto oppositely charged surfaces/molecules as well as electron-deficient groups providing its p-doping ability. Polyelectrolyte-supported dopant layers were used to generate conductive channels at the bottom or at the top of semiconducting films. Unlike to the case of sequentially processed P3HT films doped by F4TCNQ ( Moulé , J. Chem. Mater. 2015 , 27 , 5765 ; Koech , P. K. J. Mater. Chem. C 2013 , 1 , 1876 ; Schwartz , B. J. J. Phys. Chem. Lett. 2015 , 6 , 4786 ), the use of more polar CN6-CP•-K+ dopant and ultrathin polycation separation interlayer enables predominantly interfacial kind of doping placement with no or minimal intercalation of the dopant into the semiconductor bulk. The layered structure of the doped film was proved by transmission electron microscopy of the cross-section and it agrees well with other data obtained in this work. The interfacial doping enabled an impressive conductivity of 13 S/cm even for ultrathin P3HT films. We propose to explain the superior efficiency of the interfacial doping compared to the bulk doping in terms of unperturbed morphology of the semiconductor and high mobility of charge carriers, which are spatially separated from the dopant phase.
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Affiliation(s)
- Yevhen Karpov
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
| | - Nataliya Kiriy
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
| | - Petr Formanek
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
| | - Jakob Zessin
- Center for Advancing Electronics Dresden (cfaed) , Technische Universität Dresden , Dresden 01062 , Germany
| | - Mike Hambsch
- Center for Advancing Electronics Dresden (cfaed) , Technische Universität Dresden , Dresden 01062 , Germany
| | - Stefan C B Mannsfeld
- Center for Advancing Electronics Dresden (cfaed) , Technische Universität Dresden , Dresden 01062 , Germany
| | - Franziska Lissel
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
| | - Tetyana Beryozkina
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
- TOSLab , Ural Federal University named after the first President of Russia B.N.Yeltsin , Mira str., 28 , 620002 Yekaterinburg , Russia
| | - Vasiliy Bakulev
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
- TOSLab , Ural Federal University named after the first President of Russia B.N.Yeltsin , Mira str., 28 , 620002 Yekaterinburg , Russia
| | - Brigitte Voit
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
- Center for Advancing Electronics Dresden (cfaed) , Technische Universität Dresden , Dresden 01062 , Germany
| | - Anton Kiriy
- Leibniz Institute of Polymer Research Dresden , Hohe Straße 6 , 01069 Dresden , Germany
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24
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Neelamraju B, Watts KE, Pemberton JE, Ratcliff EL. Correlation of Coexistent Charge Transfer States in F 4TCNQ-Doped P3HT with Microstructure. J Phys Chem Lett 2018; 9:6871-6877. [PMID: 30450910 DOI: 10.1021/acs.jpclett.8b03104] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Understanding the interaction between organic semiconductors (OSCs) and dopants in thin films is critical for device optimization. The proclivity of a doped OSC to form free charges is predicated on the chemical and electronic interactions that occur between dopant and host. To date, doping has been assumed to occur via one of two mechanistic pathways: an integer charge transfer (ICT) between the OSC and dopant or hybridization of the frontier orbitals of both molecules to form a partial charge transfer complex (CPX). Using a combination of spectroscopies, we demonstrate that CPX and ICT states are present simultaneously in F4TCNQ-doped P3HT films and that the nature of the charge transfer interaction is strongly dependent on the local energetic environment. Our results suggest a multiphase model, where the local charge transfer mechanism is defined by the electronic driving force, governed by local microstructure in regioregular and regiorandom P3HT.
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25
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Petsagkourakis I, Tybrandt K, Crispin X, Ohkubo I, Satoh N, Mori T. Thermoelectric materials and applications for energy harvesting power generation. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2018; 19:836-862. [PMID: 31001364 PMCID: PMC6454408 DOI: 10.1080/14686996.2018.1530938] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 09/28/2018] [Accepted: 09/28/2018] [Indexed: 05/19/2023]
Abstract
Thermoelectrics, in particular solid-state conversion of heat to electricity, is expected to be a key energy harvesting technology to power ubiquitous sensors and wearable devices in the future. A comprehensive review is given on the principles and advances in the development of thermoelectric materials suitable for energy harvesting power generation, ranging from organic and hybrid organic-inorganic to inorganic materials. Examples of design and applications are also presented.
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Affiliation(s)
| | - Klas Tybrandt
- Laboratory of Organic Electronics, Linköping University, Norrköping, Sweden
| | - Xavier Crispin
- Laboratory of Organic Electronics, Linköping University, Norrköping, Sweden
| | - Isao Ohkubo
- Center for Functional Sensor & Actuator (CFSN) and International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Japan
| | - Norifusa Satoh
- Center for Functional Sensor & Actuator (CFSN) and International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Japan
| | - Takao Mori
- Center for Functional Sensor & Actuator (CFSN) and International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
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26
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Hofmann AI, Kroon R, Yu L, Müller C. Highly stable doping of a polar polythiophene through co-processing with sulfonic acids and bistriflimide. JOURNAL OF MATERIALS CHEMISTRY. C 2018; 6:6905-6910. [PMID: 30713690 PMCID: PMC6333274 DOI: 10.1039/c8tc01593g] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/15/2018] [Indexed: 05/29/2023]
Abstract
Doping of organic semiconductors is currently an intensely studied field, since it is a powerful tool to optimize the performance of various organic electronic devices, ranging from organic solar cells, to thermoelectric modules, and bio-medical sensors. Despite recent advances, there is still a need for the development of highly conducting polymer:dopant systems with excellent long term stability and a high resistance to elevated temperatures. In this work we study the doping of the polar polythiophene derivative p(g42T-T) by various sulfonic acids and bistriflimide via different processing techniques. We demonstrate that simple co-processing of p(g42T-T) with an acid dopant yields conductivities of up to 120 S cm-1, which remain stable for more than six months under ambient conditions. Notably, a high conductivity is only achieved if the doping is carried out in air, which can be explained with a doping process that involves an acid mediated oxidation of the polymer through O2. P(g42T-T) doped with the non-toxic and inexpensive 1,3-propanedisulfonic acid was found to retain its electrical conductivity for at least 20 hours upon annealing at 120 °C, which allowed the bulk processing of the doped polymer into conducting, free-standing and flexible films and renders the di-acid a promising alternative to commonly used redox dopants.
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Affiliation(s)
- Anna I Hofmann
- Department of Chemistry and Chemical Engineering , Chalmers University of Technology , 41296 Göteborg , Sweden . ;
| | - Renee Kroon
- Department of Chemistry and Chemical Engineering , Chalmers University of Technology , 41296 Göteborg , Sweden . ;
| | - Liyang Yu
- Department of Chemistry and Chemical Engineering , Chalmers University of Technology , 41296 Göteborg , Sweden . ;
| | - Christian Müller
- Department of Chemistry and Chemical Engineering , Chalmers University of Technology , 41296 Göteborg , Sweden . ;
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