An improved polymer electrolyte-based amperometric hydrogen sensor

An improved polymer electrolyte membrane (PEM) fuel cell-based amperometric hydrogen sensor that operates at room temperature has been developed. The electrolyte used in the sensor is a PVA/H3PO4 blend, which is a proton-conducting solid polymer electrolyte. A thin film of palladium is used as the anode and platinum supported on carbon as the cathode. The sensor functions as a fuel cell, H2/Pd//PVA-H3PO4//Pt/O2, and the short-circuit current is found to be linearly related to the hydrogen concentration. The basic principle, details of assembly, response behaviour of the sensor and its application are discussed.