NOx sensor is typically a high-temperature device built to detect nitrogen oxides in exhaust system environment of
automobile. The sensors can be incorporated upstream and downstream of the catalyst, for example, to provide a
feedback control loop to the Engine Control Unit (ECU) of the exhaust emission system. The ECU can than make
adjustments to optimize NOx conversion performance. Potential applications of NOx sensors as NOx emissions reduction
technology for meeting increasingly strict exhaust gas regulations.
It monitors NOx concentration downstream of NOx
adsorber catalysts to control NOx adsorber catalyst regeneration; NOx concentration before and after selective
catalytic reduction (SCR) to control and optimize urea injection and also works as NOx-OBD, a self-diagnostics by
sensor and unit to identify wear in catalysts and other components. It can be applied to gasoline lean burn engines
as part of a broader engine control or diagnostic system used to insure proper operation of the NOx emission control
system.