Ion flow oxygen sensor
Because the carrier of current in the zirconia electrolyte is oxygen ions, when the voltage is applied to the zirconia electrolytic cell, oxygen is drawn to the anode through the zirconia disk. If a perforated cover is added to the cathode of the electrolytic cell, the rate of oxygen flow to the cathode will be limited. Due to the limitation of this rate, as the applied voltage gradually increases, the current in the electrolytic cell will reach saturation. This saturation current is called the limit current, which is proportional to the oxygen concentration in the surrounding environment.
