A Computational Chemistry Study of the Influence that an Exhaust Molecule Gives to Oxygen Sensor Electrode Surface Reaction

Abstract

The surface of the electrode of the oxygen sensor for an automobile shows a complicated phenomenon due to reactions to the exhaust gas that is composed of various elements. Moreover, variations in the air/fuel ratios make it difficult to treat the reactions on the surface of the electrode on account of the coverage of oxygen. Therefore, its surface reactions of the oxygen sensor cannot be completely clarified, and this has been a bottleneck problem for the development of a sophisticated precision oxygen sensor. In this study, we applied the density functional theory and the ab-initio molecular dynamics theory to the reactions of the gas molecules on the surface of the electrode in different air/fuel ratios. As a result, we had a better understanding about the surface reactions on the molecule level and made it clear that the oxygen sensor outputs are influenced by exhaust gases such as NO, CO, CH₄, and H₂.