Amperometric Gas Sensors of High Sensitivity

Abstract

Amperometric gas sensors for the detection of ethylene, ethanol, acetaldehyde, and sulfur dioxide down to very low ppb concentrations are described. The design is based on porous Au electrodes supported on solid polymer electrolytes (SPE). Nafion as cation exchange membrane and a chemically grafted perfluorinated anion exchange membrane were employed as SPE. The sensors may be tailored to the highly sensitive detection of a specific gas by carefully selecting the component materials and the experimental conditions. The influence of gas flow rate, relative humidity of the gas streams and real surface area of the SPE electrodes are discussed.