Patent ID: 8051700

Claim:
An exhaust gas sensor, comprising: a NO 2 Nernst cell having a NO 2 sensing electrode and a first reference electrode, the first reference electrode communicating with exhaust gases in a first chamber, the NO 2 sensing electrode communicating with exhaust gases passing through a porous layer, the NO 2 Nernst cell generating a first voltage indicative of a NO 2 concentration in the exhaust gases communicating with the NO 2 sensing electrode; a NO x Nernst cell having a NO x sensing electrode and the first reference electrode, the NO x sensing electrode communicating with the exhaust gases passing through the porous layer, the NO x Nernst cell generating a second voltage indicative of a NO x concentration in the exhaust gases communicating with the NO x sensing electrode; and a NH 3 Nernst cell having a NH 3 sensing electrode and the first reference electrode, the NH 3 sensing electrode communicating with the exhaust gases passing through the porous layer, the NH 3 Nernst cell generating a third voltage indicative of a NH 3 concentration in the exhaust gases communicating with the NH 3 sensing electrode, wherein the NO 2 sensing electrode is constructed from BaFe 12 O 19 doped on a Fe site with at least one of Ca, Co, Ga, Zn, B, Rh, Mg and Sr.