Selective Determination of Hydrogen Sulfide Using SnO2–Ag Sensor Working in Non-Stationary Temperature Regime

The application of a non-stationary regime of temperature modulation in metal oxide semiconductor sensor based on SnO2–Ag leads not only to a strongly increased sensor response, but also to a considerably improved sensor selectivity toward hydrogen sulfide. Selectivity with respect to other reducing gases (CO, NH3, H2) is about five orders of magnitude, enabling a correct selective determination of H2S in the presence of interfering gas components.

Cocaine by-product detection with metal oxide semiconductor sensor arrays

Metal oxide semiconductor gas sensors based on SnO2 and Cr2O3 were modified with zeolites H-ZSM-5, Na-A and H–Y to create a gas sensor array to detect cocaine by-product, methyl benzoate. SVMs were later used with a 4 sensor array to classify 9 gases of interest.

A Mini-System Integrated with Metal-Oxide-Semiconductor Sensor and Micro-Packed Gas Chromatographic Column

In this work, a mini monitoring system integrated with a microfabricated metal oxide array sensor and a micro packed gas chromatographic (GC) column was developed for monitoring environmental gases. The microfabricated packed GC column with a 1.6 m length was used to separate the environmental gas, and the metal oxide semiconductor (MOS) array sensor, fabricated with nano-sized SnO-SnO2 sensitive materials, was able to effectively detect each component separated by GC column. The results demonstrate that the monitoring system can detect environmental gas with high precision.