1
|
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.
Collapse
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
| |
Collapse
|
2
|
Paleti SHK, Kim Y, Kimpel J, Craighero M, Haraguchi S, Müller C. Impact of doping on the mechanical properties of conjugated polymers. Chem Soc Rev 2024; 53:1702-1729. [PMID: 38265833 PMCID: PMC10876084 DOI: 10.1039/d3cs00833a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Indexed: 01/25/2024]
Abstract
Conjugated polymers exhibit a unique portfolio of electrical and electrochemical behavior, which - paired with the mechanical properties that are typical for macromolecules - make them intriguing candidates for a wide range of application areas from wearable electronics to bioelectronics. However, the degree of oxidation or reduction of the polymer can strongly impact the mechanical response and thus must be considered when designing flexible or stretchable devices. This tutorial review first explores how the chain architecture, processing as well as the resulting nano- and microstructure impact the rheological and mechanical properties. In addition, different methods for the mechanical characterization of thin films and bulk materials such as fibers are summarized. Then, the review discusses how chemical and electrochemical doping alter the mechanical properties in terms of stiffness and ductility. Finally, the mechanical response of (doped) conjugated polymers is discussed in the context of (1) organic photovoltaics, representing thin-film devices with a relatively low charge-carrier density, (2) organic thermoelectrics, where chemical doping is used to realize thin films or bulk materials with a high doping level, and (3) organic electrochemical transistors, where electrochemical doping allows high charge-carrier densities to be reached, albeit accompanied by significant swelling. In the future, chemical and electrochemical doping may not only allow modulation and optimization of the electrical and electrochemical behavior of conjugated polymers, but also facilitate the design of materials with a tunable mechanical response.
Collapse
Affiliation(s)
- Sri Harish Kumar Paleti
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - Youngseok Kim
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - Joost Kimpel
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - Mariavittoria Craighero
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - Shuichi Haraguchi
- 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
- Wallenberg Wood Science Center, Chalmers University of Technology, 41296 Göteborg, Sweden.
| |
Collapse
|