Preparation and properties of nanometer YSZ powders by glycine-nitrate process

Nanometer yttria stabilized zirconia (YSZ) powders were prepared by means of glycine-nitrate process (GNP). The phases of the synthesized product and the calcined powders were analyzed by X-ray diffraction, and the average crystallite size of the YSZ powders was calculated. The sintering shrinkage of the synthesized powders and the electrical properties of the sintered samples were studied with thermal expansion and a.c. impedance spectra, respectively. It was found that the nanometer YSZ powders can be directly synthesized by means of GNP when a molar ratio of the metal ions to glycine was 1∶2. The average crystallite size of the YSZ powders calcined at 600 and 1 000 ℃ are 9.85 and 40.5 nm, respectively. The sinterablity of the YSZ samples pre-sintered at 1 000 ℃ is significantly higher than that pre-sintered at 1 200 ℃. The relative density of the samples treated above is 99.3% and 98.6% sintered at 1 400 ℃ for 6 h, respectively, and the sintering temperature range is 1 400~1 450 ℃. The electrical conductivity of the above samples sintered at 1 450 ℃ is 0.037 and 0.021 S/cm at a measuring temperature of 850 ℃.