ELECTROCHEMICAL OXYGEN SENSORS

The use of stabilized zirconia is now well established in the measurement of oxygen dissolved in liquid metals up to 1 600-degrees-C. At this upper limit, the use of oxygen sensors operating in a temperature gradient has industrial advantages. At temperatures around 1 000-degrees-C a number of alternative systems are in use, only some of which are electrochemical. At low temperatures, below about 500-degrees-C, fluoride-based dispersed-phase electrolytes can be used in oxygen meters which measure oxygen potential in liquids, including water, down to room temperature.