Preparation of microstructured pellistors and their application for fast fuel vapor discrimination

Pellistors are well known for the detection of combustible gases. In this paper we present a simple preparation technique for micro pellistors based on a commercially available Si substrate, which is normally used for semiconducting gas sensitive layers. Catalytically active layers are achieved by drop deposition of very low volumes of noble metal containing solutions. Temperature cycling and intelligent signal processing are used to achieve high selectivity. Due to low thermal time constants discrimination between gasoline and diesel fumes is achieved within two seconds, allowing the development of a fuel sensor for integration in fuel nozzles which can prevent filling the car tank with the wrong fuel.