Abstract
A soot transducer based on the measurement of the electrical resistance value of the soot layer deposited on a finger structure was
tested at different thermophoretic potentials. The soot, similar to that issued from the Diesel engines, in terms of particle number
and size distribution, was obtained by the incomplete burning of propane and subsequent dilution. The decrease of the resistance
value in time was directly proportional with the temperature gradient. Thus a soot transducer is aimed to be used in real Diesel
exhaust, to monitor the particle release in the ambient air. An important practical aspect concerns the possibility to regenerate the
sensorial system, when their resistance reaches a certain value corresponding to the sensor saturation. The soot can be removed
by the burn off in atmosphere containing oxygen. The catalytic effect of platinum deposited on the finger structure as small
isolated islands on the surface, was investigated. It was pointed out that the platinum islands are catalytically active, determining
the soot removal at temperatures lower by 90 oC than in the case of the blank substrate.