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 similar to 870 degrees C. The oxygen sensor has a linear relationship between the log I-L and 1000/T. At 850 degrees C, a linear relationship between the limiting current I-L and oxygen concentration x(O-2) 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.