liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Operating Organic Electronics via Aqueous Electric Double Layers
Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The field of organic electronics emerged in the 1970s with the discovery of conducting polymers. With the introduction of plastics as conductors and semiconductors came many new possibilities both in production and function of electronic devices. Polymers can often be processed from solution and their softness provides both the possibility of working on flexible substrates, and various advantages in interfacing with other soft materials, e.g. biological samples and specimens. Conducting polymers readily partake in chemical and electrochemical reactions, providing an opportunity to develop new electrochemicallydriven devices, but also posing new problems for device engineers.

The work of this thesis has focused on organic electronic devices in which aqueous electrolytes are an active component, but still operating in conditions where it is desirable to avoid electrochemical reactions. Interfacing with aqueous electrolytes occurs in a wide variety of settings, but we have specifically had biological environments in mind as they necessarily involve the presence of water. The use of liquid electrolytes also provides the opportunity to deliver and change the device electrolyte continuously, e.g. through microfluidic systems, which could then be used as a dynamic feature and/or be used to introduce and change analytes for sensors. Of particular interest is the electric double layer at the interface between the electrolyte and other materials in the device,  specifically its sensitivity to charge reorganization and high capacitance.

The thesis first focuses on organic field effect transistors gated through aqueous electrolytes. These devices are proposed as biosensors with the transistor architecture providing a direct transduction and amplification so that it can be electrically read out. It is discussed both how to distinguish between the various operating mechanisms in electrolyte thin film transistors and how to choose a strategy to achieve the desired mechanism. Two different strategies to suppress ion penetration into, and thus electrochemical doping of, the organic semiconductor are presented.

The second focus of the thesis is on polarization of ferroelectric polymer films through electrolytes. A model for the interaction between the remnant ferroelectric charge in the polymer film and the mobile ionic charges of the electrolyte is presented, and verified experimentally. The reorientation of the ferroelectric polarization via the electric double layer is also demonstrated in a regenerative medicine application; the ferroelectric polarization is shown to affect cell binding, and is used as a gentle method to nondestructively detach cells from a culture substrate.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2015. , 61 p.
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1704
National Category
Physical Sciences Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:liu:diva-121805DOI: 10.3384/diss.diva-121805ISBN: 978-91-7685-944-5 (print)OAI: oai:DiVA.org:liu-121805DiVA: diva2:859450
Public defence
2015-11-09, K3, Kåkenhus, Campus Norrköping, Norrköping, 14:00
Opponent
Supervisors
Available from: 2015-10-07 Created: 2015-10-07 Last updated: 2017-02-03Bibliographically approved
List of papers
1. On the mode of operation in electrolyte-gated thin film transistors based on different substituted polythiophenes
Open this publication in new window or tab >>On the mode of operation in electrolyte-gated thin film transistors based on different substituted polythiophenes
Show others...
2014 (English)In: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 15, no 10, 2420-2427 p.Article in journal (Refereed) Published
Abstract [en]

Organic Thin Film Transistors (OTFT), gated through an aqueous electrolyte, have extensively been studied as sensors in various applications. These water-gated devices are known to work both as electrochemical (Organic ElectroChemical Transistor - OECT) and field-effect (Organic Field-Effect Transistor - OFET) devices. To properly model and predict the response of water-gated OTFT sensors it is important to distinguish between the mechanism, field-effect or electrochemical, by which the transistor is modulated and thus how the gate signal can be affected by the analyte. In this present study we explore three organic polymer semiconductors, poly-(3-hexyl-thiophene) (P3HT), poly-(3-carboxypentyl-thiphene) (P3CPT) and a co-polymer P3HT-co-poly-(3-ethoxypentanoic acid-thiophene) (monomer ratio 1:6, P3HT-COOH15) in water-gated OTFT structures. We report a set of transistor characteristics, including standard output parameters, impedance spectroscopy and current transients, to investigate the origin of the mode of operation in these water-gated OTFTs. Impedance characteristics, including both frequency and voltage dependence, were recorded for capacitor stacks corresponding to the gate/electrolyte/semiconductor/source structure. It is shown that P3HT as well as P3HT-COOH15 both can function as semiconductors in water gated OTFT devices operating in field-effect mode. P3CPT on the other hand shows typical signs of electrochemical mode of operation. The -COOH side group has been suggested as a possible anchoring site for biorecognition elements in EGOFET sensors, rendering P3HT-COOH15 a possible candidate for such applications.

Place, publisher, year, edition, pages
Elsevier, 2014
Keyword
Sensor; OTFT; Transistor; Electrolyte; EGOFET
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:liu:diva-110957 (URN)10.1016/j.orgel.2014.06.017 (DOI)000341290000035 ()
Note

Funding Agencies|European Union [248728]; Swedish Government (SFO-AFM); Onnersjo Foundation (Holmen); Knut and Alice Wallenberg Foundation (Power Papers); VINNOVA (PEA)

Available from: 2014-10-03 Created: 2014-10-01 Last updated: 2017-12-05Bibliographically approved
2. Copolythiophene-based water-gated organic field-effect transistors for biosensing
Open this publication in new window or tab >>Copolythiophene-based water-gated organic field-effect transistors for biosensing
Show others...
2013 (English)In: Journal of Materials Chemistry B, ISSN 2050-750X, Vol. 1, no 15, 2090-2097 p.Article in journal (Refereed) Published
Abstract [en]

This paper reports on the sensing of proteins using water-gated organic field-effect transistors. As a proof-of-concept, streptavidin and avidin were used, with a biotinylated polymer as the active sensing material. The latter is a copolythiophene modified to graft biotin by peptidic coupling. After characterization of its structure, it was integrated as the channel material into transistors and its interactions with several proteins were investigated. Non-specific interactions were reduced when the polymer surface was pretreated with 1-octanol. In this case, human serum albumin had no effect on the transistor characteristics whereas avidin and streptavidin led to a decrease of the drain current.

Place, publisher, year, edition, pages
Cambridge: RSC Publishing, 2013
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-89994 (URN)10.1039/c3tb00525a (DOI)
Available from: 2013-03-13 Created: 2013-03-13 Last updated: 2017-02-03
3. Phospholipid film in electrolyte-gated organic field-effect transistors
Open this publication in new window or tab >>Phospholipid film in electrolyte-gated organic field-effect transistors
Show others...
2012 (English)In: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 13, no 4, 638-644 p.Article in journal (Refereed) Published
Abstract [en]

A totally innovative electrolyte-gated field effect transistor, embedding a phospholipid film at the interface between the organic semiconductor and the gating solution, is described. The electronic properties of OFETs including a phospholipid film are studied in both pure water and in an electrolyte solution and compared to those of an OFET with the organic semiconductor directly in contact with the gating solution. In addition, to investigate the role of the lipid layers in the charge polarization process and quantify the field-effect mobility, impedance spectroscopy was employed. The results indicate that the integration of the biological film minimizes the penetration of ions into the organic semiconductor thus leading to a capacitive operational mode as opposed to an electrochemical one. The OFETs operate at low voltages with a field-effect mobility in the 10−3 cm2 V−1 s−1 range and an on/off current ratio of 103. This achievement opens perspectives to the development of FET biosensors potentially capable to operate in direct contact with physiological fluids.

Place, publisher, year, edition, pages
Elsevier, 2012
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-74742 (URN)10.1016/j.orgel.2012.01.002 (DOI)000300846200015 ()
Note
funding agencies|European Union| 248728 |Available from: 2012-02-07 Created: 2012-02-07 Last updated: 2017-12-08
4. Polarization of ferroelectric films through electrolyte
Open this publication in new window or tab >>Polarization of ferroelectric films through electrolyte
Show others...
2016 (English)In: Journal of Physics: Condensed Matter, ISSN 0953-8984, E-ISSN 1361-648X, Vol. 28, no 10, 105901Article in journal (Refereed) Published
Abstract [en]

A simplified model is developed to understand the field and potential distribution through devices based on a ferroelectric film in direct contact with an electrolyte. Devices based on the ferroelectric polymer polyvinylidenefluoride-trifluoroethylene (PVDF-TrFE) were produced – in metalferroelectric-metal, metal-ferroelectric-dielectric-metal, and metal-ferroelectric-electrolyte-metal architectures – and used to test the model, and simulations based on the model and these fabricated devices were performed. From these simulations we find indication of progressive polarization of the films. Furthermore, the model implies that there is a relation between the separation of charge within the devices and the observed open circuit voltage. This relation is confirmed experimentally. The ability to polarize ferroelectric polymer films through aqueous electrolytes, combined with the strong correlation between the properties of the electrolyte double layer and the device potential, opens the door to a variety of new applications for ferroelectric technologies, e.g., regulation of cell culture growth and release, steering molecular self-assembly, or other large area applications requiring aqueous environments.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2016
National Category
Physical Sciences Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:liu:diva-121802 (URN)10.1088/0953-8984/28/10/105901 (DOI)000371007800015 ()
Note

Funding agencies:  Swedish Governmental Agency for Innovation Systems (VINNOVA) [2010-00507]; Knut and Alice Wallenberg Foundation; Advanced Functional Materials Center at Linkoping University; Onnesjo Foundation

Available from: 2015-10-07 Created: 2015-10-07 Last updated: 2017-12-01Bibliographically approved
5. Ferroelectric Surfaces for Cell Release
Open this publication in new window or tab >>Ferroelectric Surfaces for Cell Release
Show others...
2017 (English)In: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 228, 99-104 p.Article in journal (Refereed) Published
Abstract [en]

Adherent cells cultured in vitro must usually, at some point, be detached from the culture substrate. Presently, the most common method of achieving detachment is through enzymatic treatment which breaks the adhesion points of the cells to the surface. This comes with the drawback of deteriorating the function and viability of the cells. Other methods that have previously been proposed include detachment of the cell substrate itself, which risks contaminating the cell sample, and changing the surface energy of the substrate through thermal changes, which yields low spatial resolution and risks damaging the cells if they are sensitive to temperature changes. Here cell culture substrates, based on thin films of the ferroelectric polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) co-polymer, are developed for electroactive control of cell adhesion and enzyme-free detachment of cells. Fibroblasts cultured on the substrates are detached through changing the direction of polarization of the ferroelectric substrate. The method does not affect subsequent adhesion and viability of reseeded cells.

Place, publisher, year, edition, pages
Elsevier, 2017
National Category
Physical Sciences Electrical Engineering, Electronic Engineering, Information Engineering Clinical Science
Identifiers
urn:nbn:se:liu:diva-121804 (URN)10.1016/j.synthmet.2017.04.013 (DOI)000401599600015 ()
Note

Funding agencies: Swedish Governmental Agency for Innovation Systems (VINNOVA) [2010-00507]; Knut and Alice Wallenberg Foundation; Onnesjo Foundation

Available from: 2015-10-07 Created: 2015-10-07 Last updated: 2017-06-13Bibliographically approved

Open Access in DiVA

fulltext(2087 kB)229 downloads
File information
File name FULLTEXT01.pdfFile size 2087 kBChecksum SHA-512
7e6f15c352ab4485238c230c38865602d4e49387487eea2c62fc64a0bada783f3e9b7376bd4f5adb4f56b57859cd8f8b98f0f63dc91f0d63f0c7ab3bcf0b827c
Type fulltextMimetype application/pdf
omslag(569 kB)34 downloads
File information
File name COVER01.pdfFile size 569 kBChecksum SHA-512
4218e07aa288204b189e8679afc9268d6fd2f77d3cb257789907598db8595cad86e7609d099280bc928f2dba67d9871a8597e8b621454176bf057d03812bd373
Type coverMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Toss, Henrik

Search in DiVA

By author/editor
Toss, Henrik
By organisation
Physics and ElectronicsFaculty of Science & Engineering
Physical SciencesElectrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 229 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
isbn
urn-nbn

Altmetric score

doi
isbn
urn-nbn
Total: 2059 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf