Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

Spark-plasma sintering (SPS) process was used to sinter ZrO 2 (8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (1450°C 4 h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (F m3m ). The finer crystallite size (D 111 ) of the SPS pellet is 154 nm and D 111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol −1 , which is in good agreement with CS pellet (96 kJ mol −1 ), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.