NOx-decomposing electrode and NOx concentration-measuring apparatus

摘要

A detecting electrode (42) comprises a first cermet electrode layer (62) formed directly on a solid electrolyte layer (12d) and a second cermet electrode layer (64) formed on the first cermet electrode layer (62). A ratio between an alloy of Pt-Rh and ZrO2 in the first cermet electrode layer (62) ranges from 20:80 to 50:50 by volume ratio. On the other hand, a ratio between an alloy of Pt-Rh and ZrO2 in the second cermet electrode layer (64) ranges from 60:40 to 50:50 by volume ratio.