Sensing characteristics of a limiting current oxygen sensor with (8YSZ)0.85(Cr2O3)0.15 dense diffusion barrier.

(8YSZ)_1−x(Cr₂O₃)_x (x = 0, 0.05, 0.10, 0.15) are prepared by the co-precipitation method. Diffraction peaks of the samples belonged to the cubic fluorite structure. Conductivity decreases first and then increases with increasing Cr₂O₃ content. An oxygen sensor based on 8YSZ solid electrolyte and (8YSZ)_0.85(Cr₂O₃)_0.15 diffusion barrier is prepared by the Pt slurry bonding method. The sensor has a limiting current plateau at 2% oxygen concentrations within 720 ~ 870 °C. The oxygen sensor has a linear relationship between the log I_L and 1000/T. At 850 °C, a linear relationship between the limiting current I_L and oxygen concentration x(O₂) is established for the oxygen sensor. The oxygen sensor is provided with a limiting current plateau within the experimental concentration division, and the limiting current plateau is not affected by x(CO₂) and p(H₂O). I-V curves of the oxygen sensor overlap, and the limiting current plateaus are almost equal under the long-term high-temperature operating conditions of 144 h. [ABSTRACT FROM AUTHOR]