Improvement of the sensitivity of a conductometric soot sensor by adding a conductive cover layer

Title data

Bartscherer, Peter ; Moos, Ralf:
Improvement of the sensitivity of a conductometric soot sensor by adding a conductive cover layer.
In: Journal of Sensors and Sensor Systems. Vol. 2 (2013) Issue 2 . - pp. 95-102.
ISSN 2194-878X
DOI: https://doi.org/10.5194/jsss-2-95-2013

Official URL:

Abstract in another language

Diesel particulate filters are emission-relevant devices of the exhaust gas aftertreatment system. They need to be monitored as a requirement of the on-board diagnosis. In order to detect a malfunction, planar sensors with interdigital electrodes on an insulating substrate can be installed downstream of the filter. During the loading phase, soot deposits onto the electrodes, but the sensor remains blind until the percolation threshold has been reached (initiation time) and the sensor current starts to flow. In order to detect small soot concentrations downstream of the filter from small defects, this initiation time needs to be as low as possible. One may reduce the initiation time by covering the interdigital electrodes with an electrically conductive layer. Using finite element method (FEM) simulations, the influence of conductivity and thickness of such a coating on the initiation time are determined. It is found that a thin, screen printable coating with a thickness of 20 μm and a conductivity in the range of 10^−3 to 10^−1 S/m may reduce the initiation time by about 40%. The FEM results were verified by a commercially available thick film resistor paste with a conductivity of 0.45 mS/m, showing an improvement of about 40% compared to an uncoated sensor.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Institutions of the University:	Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Functional Materials > Chair Functional Materials - Univ.-Prof. Dr.-Ing. Ralf Moos Research Institutions > Research Units > BERC - Bayreuth Engine Research Center Faculties Faculties > Faculty of Engineering Science > Chair Functional Materials Research Institutions Research Institutions > Research Units Profile Fields > Advanced Fields > Advanced Materials Research Institutions > Research Centres > Bayreuth Center for Material Science and Engineering - BayMAT Profile Fields Profile Fields > Advanced Fields Research Institutions > Research Centres
Result of work at the UBT:	Yes
DDC Subjects:	600 Technology, medicine, applied sciences > 620 Engineering
Date Deposited:	12 Jan 2015 13:25
Last Modified:	14 Jul 2022 10:30
URI:	https://eref.uni-bayreuth.de/id/eprint/5475