Please use this identifier to cite or link to this item: http://hdl.handle.net/1822/31116

TitleElectrochemical behaviour of nanocomposite Agx:TiN thin films for dry biopotential electrodes
Author(s)Pedrosa, Paulo Eduardo Teixeira Baptista
Alves, Eduardo
Barradas, Nuno P.
Martin, Nicolas
Fiedler, P.
Haueisen, J.
Vaz, F.
Fonseca, C.
KeywordsTiN
Ag-doping
Biopotential electrodes
Dry electrodes
EIS
Dry electrodes, EIS
Issue date2014
PublisherElsevier
JournalElectrochimica Acta
Abstract(s)Agx:TiN nanocomposite thin films with Ag contents ranging from ~0.1 up to ~47.5 at% obtained by DC reactive sputtering on glass substrates were characterized regarding their electrochemical performance in a synthetic sweat solution, aiming at studying their potential application as bioelectrodes. Correlations between the electrochemical behaviour and their exhibited morphology (porosity) and structure (grain size) were established and discussed in detail. The coatings’ open circuit potential (OCP) is ruled by the Ag/TiN galvanic coupling and it decreased with the increase of the Ag content. For Ag contents up to 12.1 at% the OCP was found to be close to that of bulk Ag, but for higher Ag contents the OCP of the Agx:TiN samples displayed a steep drop, which was ascribed to the effect of Ag grain size reduction (from ~28 to ~10 nm). Both SEM and voltammetric experiments confirmed a gradual porosity decrease (densification) of the coatings with increasing Ag content, leading to a reduction of the electroactive area. All samples, besides displaying good chemical stability in chloride media, exhibited low impedance moduli and electrochemical noise similar to that of commercial Ag/AgCl electrodes, thus making them suitable to be used as bioelectrodes, from the electrochemical point of view.
TypeArticle
URIhttp://hdl.handle.net/1822/31116
DOI10.1016/j.electacta.2014.01.082
ISSN0013-4686
Publisher versionhttp://www.sciencedirect.com/science/article/pii/S0013468614001509
Peer-Reviewedyes
AccessRestricted access (UMinho)
Appears in Collections:CDF - GRF - Artigos/Papers (with refereeing)

Files in This Item:
File Description SizeFormat 
Pedrosa et al. Electrochimica Acta.pdf
  Restricted access
Manuscrip2,1 MBAdobe PDFView/Open    Request a copy!

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID