Microporous Stilbite single crystals for alcohol sensing

The possibility of shape-selective resistive gas sensors for polar molecules using the microporous alumo-silicate Stilbite is investigated. The electrical impedance of natural Stilbite single crystals at 80 degrees C decreases in presence of methanol, 2-propanol and 3-pentanol, but increases with increasing water and neo-pentanol vapour pressure. The interaction can be described by a Langmuir-type adsorption equation. The conductivity effects are interpreted mainly by mobility effects, due to sterical interactions in the zeolite channels.