Temperature-independent TiO<inf>2</inf>-ZrO<inf>2</inf> oxygen lambda sensor

Abstract

The electromotive force (EMF) of a new type of YSZ-based planar oxygen sensor exposed to simulated automobile exhaust gas, with no air reference, was measured under different conditions. A sensor with two parallel Pt electrodes, one coated with Ti 0 . 75 Zr 0 . 25 O 2 (Ti-Zr) as a solidstate reference, was fabricated. The performance of this sensor was measured at different temperatures and λs, i.e. the actual air/fuel ratio to that of stoichiometric value. The transition in EMF occurs around λ=1. Also the amplitude of the transition between rich (λ=0.8) and lean (λ=1.2) measured at a temperature range of 350-650 o C remains almost constant, indicating a temperature-independent performance.