Yttria-stabilized zirconia electrolytes with diverse microstructures were prepared by using nano-size (Y2O3)0.08(ZrO2)0.92 powders as precursors by conventional sintering in air. The electrolytes were tested by alternating-current impedance spectroscopy to elucidate the contribution of intragranular and intergranular conductivity to the total ionic conductivity.

The intragranular conductivity and intergranular conductivity were correlated with the microstructures of the electrolyte to interpret the transportation of O ions through the electrolyte. The intragranular conductivity was found to be dominated mainly by the relative density while the intergranular conductivity depended strongly upon the grain size and the grain boundary area of the electrolyte. The sintering temperature and isothermal time dependence of ionic conductivity reached a maximum value of 0.105S/cm at a sintering temperature of 1350C for 4h and 0.112S/cm at a holding time of 8h at 1250C when measured at 1000C, respectively.

Influence of Microstructure on the Ionic Conductivity of Yttria-Stabilized Zirconia Electrolyte. X.J.Chen, K.A.Khor, S.H.Chan, L.G.Yu: Materials Science and Engineering A, 2002, 335[1-2], 246-52