DONOR-DOPED GD2TI2O7 AS A SEMICONDUCTOR-TYPE OXYGEN SENSOR

The results of electrical conductivity measurements of Gd-2(Ti1-xNbx)2 O(7+delta) show that at x=0.005, background accepters become compensat ed and the conductivity follows a clear P-O2(-1/6) dependence over bro ad P-O2 and T limits. The restriction this places on background accept ers is analyzed. While conductivity transients measured in response to periodic P-O2 variations are rapid, they correspond to surface reacti ons that are superimposed on longer-term diffusion-controlled transien ts. The source of more complex P-O2 dependencies of conductivity for o ther values of x is also discussed.