Oxygen sensor composition

- Mar 26, 2018-

Oxygen sensors use the Nernst principle.

The core element is a porous ZrO2 ceramic tube, which is a solid electrolyte with porous Pt electrodes sintered on both sides. At a certain temperature, due to the difference in oxygen concentration at both sides, the oxygen molecules on the high-concentration side (the inside of the ceramic tube 4) are adsorbed on the platinum electrode and combine with the electron (4e) to form the oxygen ion O2-, making the electrode positively charged, O2 The ions migrate through the oxygen ion vacancy in the electrolyte to the low oxygen concentration side (the exhaust gas side), causing the electrode to be negatively charged, ie to generate a potential difference.