Effect of Oxygen Content on Impedance Spectra of PtRh Electrodes for NOX Sensing Applications


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Growing awareness of dangers related to NOX emission by industry and road transportation has resulted in increasing demand for sensors detecting NOX. An important class of these sensors use Pt-based electrodes applied on yttria-stabilized zirconia (YSZ) substrates. Performance of such sensors depends on redox reactions occurring at electrodes in the tested atmospheres. Impedance spectra and j-U curves of PtRh electrodes were measured in a 3-electrode mode, using Pt metal pads as counter and reference electrodes. The data were collected in a 10mHz- 100kHz frequency range at temperatures from 450 to 750°C. Each series of measurements was carried out in a gas mixture with different oxygen content ranging from 0 to 21 vol%. It was found out that the low-frequency part of the impedance spectra (characterizing electrode processes) was sensitive to the oxygen content in the gas mixtures.



Materials Science Forum (Volumes 514-516)

Edited by:

Paula Maria Vilarinho




P. Kurek et al., "Effect of Oxygen Content on Impedance Spectra of PtRh Electrodes for NOX Sensing Applications", Materials Science Forum, Vols. 514-516, pp. 1379-1384, 2006

Online since:

May 2006




[1] Emission Control Technology for Heavy Duty Vehicles, vol. 2 and 3, The European Commission DG ENTR, May (2002).

[2] D. Kohl, J. Phys. D: Appl. Phys. 34 (2001) R125.

[3] J. Riegel, H. Neumann, H. -M. Wiedenmann, Solid State Ionics 152-153 (2002) 783.

[4] E. Römer, Ph.D. Thesis, Twente University Press (2001).

[5] Y.J. Mergler, B.E. Nieuwenhuys, Appl. Catal. B 12 (1997) 95.

[6] J. E. Bauerle, J. Phys. Chem Solids 30 (1969) 2657.

[7] M. J. Jørgensen, M. Mogensen, J. of Electrochemical Soc. 148 (2001) A433.

[8] P. Kurek, S. Thiemann-Handler, M. Marzantowicz, M. Foltyn, Ionics 10 (2004) 469.

[9] W-F. Zhang, P. Schmidt-Zhang, U. Guth, Solid State Ionics 169 (2004) 121.