HYDROGEN SENSOR BASED ON YTTRIA-STABILIZED ZIRCONIA ELECTROLYTE AND Rh-PROMOTED ITO SENSING ELECTRODE

摘要

A potentiometric H_2 sensor has been developed for leak detection near fuel cell and/or reformer systems. The sensor is based on a catalytically active Rh:ITO sensing electrode and an AgPd reference electrode attached to an yttria-stabilized zirconia (YSZ) electrolyte. This electrode/electrolyte combination constitutes an electrochemical cell for which the open circuit potential (OCP) in air is sensitive to the concentration of hydrogen. The sensing approach is based on the difference in oxidation rate of hydrogen at the different electrode materials.