Multiple Organic Gas Detection by the Ball Surface Acoustic Wave Sensor

We discovered naturally collimated beam of surface acoustic wave (SAW) on balls and developed ball SAW sensor. It has an unique advantage of ultra-multiple roundtrips more than 100 turns. We achieved for the first time, sensing range of hydrogen from 10 ppm (0.001%) to 100% with a single sensor element, essential for hydrogen stations fuel cell cars. In this study, we describe the development of a MEMS palmtop gas chromatograph (GC) for organic volatile compound (VOC). It realized detection of hazardous gases in a reasonably short time, which will be applied for on-site monitoring of natural gas and fuel cell gases used at cars, home and smart grids.