A novel thick film sensor for simultaneous O2 and NO monitoring in exhaust gases

A miniaturized two-electrode sensor for the simultaneous detection of oxygen and nitrogen monoxide in oxygen, nitrogen, NO gas mixtures has been developed by using thick film technology. The solid state electrochemical sensor, based on yttria-stabilized zirconia, operates in the amperometric mode. Oxygen concentrations ranging up to 5 vol.% and NO concentrations ranging up to 2500 ppm can be detected separately and simultaneously. The diffusion properties of the diffusion barrier of the sensor have been determined by the current dependence on the working temperature.