Development of a hydrogen sensor based on solid polymer electrolyte membranes

A compact hydrogen gas sensor based on solid polymer electrolyte (Nafion 117), working under amperometric conditions at room temperature with minor water maintenance, has been developed. Electrodes were prepared chemically by using the impregnation–reduction method. The polymer was platinized by using a platinum chloro amino complex and sodium tetrahydro borate as impregnating salt and reducing agent, respectively. The thin Pt films were characterized by XRD, infrared spectroscopy, optical microscopy, scanning electron microscopy and EDAX. Sensor measurements were performed under amperometric short-circuit current conditions. A maximum sensitivity of about 0.01 μA cm−2 ppm−1 was obtained. The response time was observed to be in the range of 10–50 s. A reproducible response with an approximately linear current versus PH2PH2 has been observed for the range of hydrogen concentration from 1 to 10%.