Nafion based amperometric hydrogen sensor

A Nafion based amperometric hydrogen sensor that operates at room temperature has been developed. The electrolyte used in the sensor is Nafion 117, which is a proton conducting solid polymer electrolyte. Palladium catalyst was used on the sensing side and platinum supported on carbon on the air side. The sensor functions as fuel cell, H2/Pd//Nafion//Pt/O2 and the short circuit current is measured. The short circuit current is found to be linear with respect to concentration of hydrogen on the sensing side. The sensor is able to detect the concentration of hydrogen in argon down to ppb level. Details of assembly of the sensor, response behavior and applications are discussed.