HO2S - ZIRCONIA (ZrO2) OPERATION PRINCIPLE (VIN 6)

The Zirconia (ZrO₂ ) which is coated with Platinum (Pt) on both sides will generate the voltage if the density of oxygen on atmosphere side and exhaust gas side is different in high temperature.

In other words oxygen ion moves from high-density side (Atmosphere) to low-density side (exhaust gas), at a result Sensor Voltage is generated by Nernst equation between two electrodes.

Fig 1: Identifying Heated Oxygen Sensor (HO2S) Function Diagram

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