Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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
Upscaling Organic Electronic Devices
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]

Conventional electronics based on silicon, germanium, or compounds of gallium require prohibitively expensive investments. A state-of-the-art microprocessor fabrication facility can cost up to $15 billion while using environmentally hazardous processes. In that context, the discovery of solution-processable conducting (and semiconducting) polymers stirred up expectations of ubiquitous electronics because it enables the mass-production of devices using well established high-volume printing techniques.

In essence, this thesis attempts to study the characteristics and applications of thin conducting polymer films (<200 nm), and scale them up to thick-films (>100 μm). First, thin-films of organic materials were combined with an electric double layer capacitor to decrease the operating voltage of organic field effect transistors. In addition, ionic current-rectifying diodes membranes were integrated inside electrochromic displays to increase the device’s bistability and obviate the need for an expensive addressing backplane.

This work also shows that it is possible to forgo the substrate and produce a self-standing electrochromic device by compositing the same water-processable material with nanofibrillated cellulose (plus a whitening pigment and high-boiling point solvents). In addition, we investigated the viability of these (semi)conducting polymer nanopaper composites in a variety of applications. This material exhibited an excellent combined electronic-ionic conductivity. Moreover, the conductivities in this easy-to-process composite remained constant within a wide range of thicknesses. Initially, this (semi)conducting nanopaper composite was used to produce electrochemical transistors with a giant transconductance (>1 S). Subsequently, it was used as electrodes to construct a supercapacitorwhose capacitance exceeds 1 F.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2015. , 62 p.
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1711
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:liu:diva-122022DOI: 10.3384/diss.diva-122022ISBN: 978-91-7685-929-2 (print)OAI: oai:DiVA.org:liu-122022DiVA: diva2:861292
Public defence
2015-11-13, Resursen, Pronova, Norrköping Konferens, St Persgatan 19, Norrköping, 10:15 (English)
Opponent
Supervisors
Available from: 2015-10-16 Created: 2015-10-16 Last updated: 2015-10-20Bibliographically approved
List of papers
1. Ultra-low voltage air-stable polyelectrolyte gated n-type organic thin film transistors
Open this publication in new window or tab >>Ultra-low voltage air-stable polyelectrolyte gated n-type organic thin film transistors
2011 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 99, no 6, 063305- p.Article in journal (Refereed) Published
Abstract [en]

Complementary circuits, processing digital signals, are a cornerstone of modern electronics. Such circuits require both p-and n-type transistors. Polyelectrolytes are used as gate insulators in organic thin film transistors (OTFTs) to establish an electric double layer capacitor upon gate bias that allows low operational voltages (andlt;1 V). However, stable and low-voltage operating n-channel organic transistors have proven difficult to construct. Here, we report ultra-low voltage n-channel organic polymer-based transistors that are stable in ambient atmosphere. Our n-type OTFTs exhibit on/off ratios around 10(3) for an applied drain potential as low as 0.1 V. Since small ions are known to promote electrochemical reactions within the semiconductors channel bulk and typically slow down the transistor, we use a solid polycationic gate insulator that suppresses penetration of anions into the n-channel semiconductor. As a result, our n-channel OTFTs switch on in under 5 ms and off in less than 1 ms.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2011
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-70331 (URN)10.1063/1.3626587 (DOI)000293857700076 ()
Note
|Swedish Government||Swedish Foundation for Strategic Research (OPEN)||Knut and Alice Wallenberg Foundation||Onnesjo Foundation||Available from: 2011-09-02 Created: 2011-09-02 Last updated: 2017-12-08
2. Low-voltage ambipolar polyelectrolyte-gated organic thin film transistors
Open this publication in new window or tab >>Low-voltage ambipolar polyelectrolyte-gated organic thin film transistors
2012 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 100, no 18, 183302- p.Article in journal (Refereed) Published
Abstract [en]

Organic transistors that use polyelectrolytes as gate insulators can be driven at very low voltages (andlt;1 V). The low operating voltage is possible thanks to the formation of electric double layers upon polarization, which generates large electric fields at the critical interfaces in the device structure. In this work, we use a semiconducting blend (of a high electron affinity polymer and a low ionization potential one) in conjunction with a solid polyelectrolyte insulator to fabricate low-voltage ambipolar organic transistors. For both n- and p-channel operation, we use a polycation with readily mobile-yet large enough to limit bulk doping of the semiconductor-counterions.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2012
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-77731 (URN)10.1063/1.4709484 (DOI)000303598600055 ()
Note
Funding Agencies|EU through the EC|212311|Swedish Government (Advanced Functional Materials)||Swedish Foundation for Strategic Research (OPEN)||Knut and Alice Wallenberg Foundation||Onnesjo Foundation||Available from: 2012-05-30 Created: 2012-05-28 Last updated: 2017-12-07
3. An Electrochromic Bipolar Membrane Diode
Open this publication in new window or tab >>An Electrochromic Bipolar Membrane Diode
2015 (English)In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 27, no 26, 3909-+ p.Article in journal (Refereed) Published
Abstract [en]

Conducting polymers with bipolar membranes (a complementary stack of selective membranes) may be used to rectify current. Integrating a bipolar membrane into a polymer electrochromic display obviates the need for an addressing backplane while increasing the devices bistability. Such devices can be made from solution-processable materials.

Place, publisher, year, edition, pages
Wiley-VCH Verlag, 2015
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:liu:diva-120341 (URN)10.1002/adma.201500891 (DOI)000357688900008 ()26016815 (PubMedID)
Note

Funding Agencies|Swedish foundation for strategic research; Knut and Alice Wallenberg foundation; VINNOVA; Advanced Functional Materials Center at Linkoping University; European Research Council [307596]

Available from: 2015-07-31 Created: 2015-07-31 Last updated: 2017-12-04
4. A substrate-free electrochromic device
Open this publication in new window or tab >>A substrate-free electrochromic device
Show others...
2015 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Electrochromic displays based on conducting polymers offer higher contrast, are cheaper, faster, more durable, and easier to synthesize as well as to process than their non-polymeric counterparts. The field of organic electrochromics has made considerable strides in the last decade with the development of new materials and methods. Here, we present a cellulose composite combining PEDOT:PSS and TiO2 that is a free-standing electrochromic material. Owing to the excellent refractive properties of TiO2, this nanocomposite is white in the neutral state and, when reduced, turns blue resulting in a color contrast exceeding 30. The composite has a granular morphology and, as shown by AFM, an intermingling of TiO2 and PEDOT:PSS at the surface. Variation of TiO2 within the material led to a trade-off in optical and electrical properties. A proof of concept free-standing electrochromic device was fabricated by casting several layers, which was found to be stable over 100 cycles.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:liu:diva-122020 (URN)
Available from: 2015-10-16 Created: 2015-10-16 Last updated: 2017-02-03Bibliographically approved
5. Enabling organic power electronics with a cellulose nano-scaffold
Open this publication in new window or tab >>Enabling organic power electronics with a cellulose nano-scaffold
Show others...
2015 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Exploiting the nanoscale properties of certain materials enables the creation of new materials with a unique set of properties. Here, we report on an electronic (and ionic) conducting paper based on cellulose nanofibrils (CNF) composited with poly(3,4-ethylene-dioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS), which may be facilely processed into large three-dimensional geometries, while keeping unprecedented electronic and ionic conductivities of 140 S/cm and 20 mS/cm, respectively. This is achieved by cladding the CNF with PEDOT:PSS, and trapping an ion-transporting phase in the interstices between these nanofibrils. The unique properties of the resulting nanopaper composite have been used to demonstrate (electrochemical) transistors, supercapacitors and conductors resulting in exceptionally high device parameters, such as an associated transconductance, charge storage capacity and current level beyond 1 S, 1 F and 1 A, respectively.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:liu:diva-122021 (URN)
Available from: 2015-10-16 Created: 2015-10-16 Last updated: 2017-02-03Bibliographically approved

Open Access in DiVA

fulltext(2063 kB)243 downloads
File information
File name FULLTEXT01.pdfFile size 2063 kBChecksum SHA-512
9187ce9025884fcb7fde1862bb68cd24a5d67c75cd63ad0f76f6b549204b018037a0f0b5001d15d7d5eaa95172c5db68d7479e7d35576daf1884cca1e9ec692b
Type fulltextMimetype application/pdf
omslag(37 kB)12 downloads
File information
File name COVER01.pdfFile size 37 kBChecksum SHA-512
d7e91f2e7348746398a4981688944ef880213b61aa01784c7e5683f815216d868340dfa3a2a777ffc473613c8b522ecaf6459e6b8238834c5735fd11850a3321
Type coverMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Malti, Abdellah

Search in DiVA

By author/editor
Malti, Abdellah
By organisation
Physics and ElectronicsFaculty of Science & Engineering
Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 243 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: 899 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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