What happens when a Teledyne Micro-fuel cell O2 sensor sees NO and/or CO?
NOx usually refers to a mixture of NO and NO2. This is because NO is easily oxidized into NO2 if O2 or other oxidizing agents are present. NOx will interfere with O2 detection by B2C sensors. In theory, 1 ppm NO will reading 0.5 ppm O2. CO is a carbon oxide, but not necessarily an oxidizing agent. It is normally considered as a reducing agent, somewhat like H2. CO can be oxidized by O2 to form CO2 and produce heat. This reaction is not naturally occurring and must be catalyzed in high temperatures. In fact, CO can be used by a high temperature Fuel Cell (solid oxide fuel cell, SOFC) operated at 1000C to produce electricity. The mechanism of 10% CO produces 1 ppm O2 negative reading is not clear. It is possible that CO may absorbed over the cathode surface to lead the negative output. NO2 (sometimes,as N2O4 if under pressure) is an oxidizing agent. It acts like O2. However, NO is complicated. It can be oxidized by O2 into NO2 (like a reducing agent), but it also can be reduced into N2 (
