Heath, J.P., Harding, J.H. orcid.org/0000-0001-8429-3151, Sinclair, D.C. orcid.org/0000-0002-8031-7678 et al. (1 more author) (2019) The analysis of impedance spectra for core–shell microstructures : why a multiformalism approach is essential. Advanced Functional Materials, 29 (38). ISSN 1616-301X
Abstract
The impedance response of a core–shell microstructure with 80% core volume fraction has been simulated using finite‐element modeling and compared to two equivalent circuits for a wide range of shell permittivity and conductivity values. Different equivalent circuits, corresponding to different variants of the well‐known brick layer model, are applicable for different combinations of material properties in the microstructure. When the shell has a similar conductivity or permittivity to the core, adding a parallel pathway increases the accuracy of the fit by ≈±10%. When both the conductivity and permittivity values of the core and shell regions are different the series circuit is a better fit. This is confirmed by multiformalism impedance analysis, which reveals features in the data that are not apparent using a single formalism. Finally, the conductivity and permittivity values for both the shell and core are extracted from the simulated spectra using all formalisms and compared to the original input values. The accuracy of the extracted values often depends on the impedance formalism used. It is concluded that impedance spectroscopy data must be analyzed using multiple formalisms when considering core–shell microstructures.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 Wiley. This is an author-produced version of a paper subsequently published in Advanced Functional Materials. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | composite materials; core/shell microstructures; dielectrics; impedance spectra; simulations |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Funding Information: | Funder Grant number Engineering and Physical Science Research Council (EPSRC) EP/G005001/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 19 Sep 2019 11:03 |
Last Modified: | 23 Jul 2020 00:38 |
Status: | Published |
Publisher: | Wiley |
Refereed: | Yes |
Identification Number: | 10.1002/adfm.201904036 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:151080 |