Change search
ReferencesLink to record
Permanent link

Direct link
Water dispersible carbon nanotube/polyaniline composite: study of the morphology and electrical conductivity
KTH, School of Information and Communication Technology (ICT), Electronic Systems.
KTH, School of Information and Communication Technology (ICT), Electronic Systems.
KTH, School of Information and Communication Technology (ICT), Electronic Systems.
Department of Engineering Sciences, Uppsala University.
(English)In: Synthetic metals, ISSN 0379-6779Article in journal (Other academic) Submitted
National Category
Composite Science and Engineering
URN: urn:nbn:se:kth:diva-116708OAI: diva2:600465

QS 2013

Available from: 2013-01-24 Created: 2013-01-24 Last updated: 2013-01-25Bibliographically approved
In thesis
1. Nanofibrillar Materials for Organic and Printable Electronics
Open this publication in new window or tab >>Nanofibrillar Materials for Organic and Printable Electronics
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In recent years, organic electronics have attracted great attention due to their multiple advantages such as light weight, flexibility, large area fabrication and cost-effective production processes. The recent progress in fabricating organic electronic devices has been achieved with the development of new materials which provide competing functionalities to the electronics devices.  However, as it happens with all type of technologies, organic electronics is not free from challenges. In the latest OE-A Roadmap for organic and printed electronics (2011), the “red brick walls” were identified, and the following three main challenges were pointed out as the potential roadblocks from the material point of view: electrical performance, solution processability (especially formulations in non-toxic solvents) and environmental stability. Currently there is a significant increasing interest in optimizing or developing novel materials to meet those requirements.


This thesis presents processing development and study of nanofibrillar materials and deals with the optimization for its applicability for organic electronics. The overall work presented in the thesis is based on three nanofibrillar materials: Polyaniline (PANI), carbon nanotubes (CNTs) and the CNT/PANI composite. First, the solution processability of carbon nanotubes and polyaniline is studied respectively, and through covalent and non-covalent methods, stable aqueous dispersions of these materials are successfully achieved.


Second, a composite consisting of multi-walled carbon nanotubes (MWCNTs) and PANI with a core-shell structure is developed and characterized. The investigation of the effects of the loading and type of nanotubes incorporated in the composite material, led to understanding on the fundamental theory underlying the composite morphology. Based on those findings and by carefully optimizing the synthesis procedure, water dispersible MWCNT/PANI nanofibrillar composite is successfully synthesized becoming compatible with solution processable techniques, such as spray coating and potentially with printing technology. With the incorporation of carbon nanotubes, the nanofibrillar composite reaches conductivities 20 times higher than that of the pure polymer. Moreover, the presence of the nanotubes in the composite material decelerates up to 60 times the thermal ageing of its conductivity, making the polymer more robust and suitable for possible manufacturing processes. Furthermore, the composite material still retains the advantageous properties of PANI: electrochromism, tunable conductivities, and sensing capabilities.


Third, the stable dispersions of PANI, CNTs and MWCNT/PANI composite were effectively deposited by spray coating technique on several low-cost substrates (PET, PEN, polyimide and papers), and homogeneous, flexible, large-area films were fabricated. Additionally, by spraying the materials on pre-fabricated inkjet printed electrodes, a pH sensor based on the MWCNT/PANI composite and a humidity sensor based on functionalized MWCNTs capable of working at GHz range were demonstrated, which shows that the nanofibrillar materials studied in this thesis work are promising sensor materials for wireless application at ultra-high frequency (UHF) band.


Finally, the humidity sensor was integrated into a sensor-box demonstrating a hybrid interconnection platform where printed electronics can be seamlessly integrated with silicon-based electronics. The integration closes the gap between the two technologies, anticipating the adaption of organic electronic technologies.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. xiv, 87 p.
Trita-ICT-ECS AVH, ISSN 1653-6363 ; 12:09
Organic electronics, polyaniline, carbon nanotubes, composite, spray coating, solution processability, morphology, electrical conductivity, ageing, sensor, system integration
National Category
Composite Science and Engineering
urn:nbn:se:kth:diva-116714 (URN)978-91-7501-615-3 (ISBN)
Public defence
2013-02-18, Sal D, Forum, KTH-ICT, Isafjordsgatan 39, Kista, 14:00 (English)

QC 20130125

Available from: 2013-01-25 Created: 2013-01-24 Last updated: 2013-01-25Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Lopez Cabezas, AnaFeng, YiZheng, Li-Rong
By organisation
Electronic Systems
In the same journal
Synthetic metals
Composite Science and Engineering

Search outside of DiVA

GoogleGoogle Scholar
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

Total: 92 hits
ReferencesLink to record
Permanent link

Direct link