4.1.3 Pt/Au based Sensor with a PMMA –Film for detecting CO in a Hydrogen Atmosphere

Even small traces of carbon monoxide in the fuel gas lead to a degradation of performance in low temperature polymer electrolyte membrane (PEM) fuel cell systems. Therefore a sensor which is capable of detecting CO in a ppm range in a hydrogen rich atmosphere is a great advantage. In this talk a new gas sensitive layer to be used as suspended gate in an existing CCFET based sensor system is presented. The new gate material is based on a platinum/gold alloy and covered with a thin polymethylmethacrylat (PMMA) layer. A simple experiment was designed to qualify the sensitive layer measuring the work function change with a Kelvin probe system. Here measurements will be presented in an atmosphere of 95% argon, 4% hydrogen and 1% carbon dioxide. The carbon monoxide concentration was up to 50ppm.