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Published online by Cambridge University Press: 20 February 2017
Nanocrystalline 8 and 12 mol % yttria stabilized zirconia (YSZ) powders with fluorite-type structure were synthesized by a precipitation method. Powders were characterized by X-ray diffraction, differential scanning calorimetry, thermogravimetry, and nitrogen adsorption analyses. Precipitation produced amorphous powder which crystallized at approximately 450-470 °C into a cubic phase with a crystallization enthalpy ranging from 13.7 ± 0.6 kJ/mol for 8YSZ to 11.7 ± 0.5 kJ/mol for 12YSZ. Integral heat of water adsorption at room temperature measured on 8YSZ was -63 ± 2 kJ/mol for coverage 4.1 ± 0.1H2O/nm2. Drop solution calorimetry experiments were performed in a custom made Calvet twin calorimeter using sodium molybdate 3Na2O 4MoO3 solvent. The preliminary values for surface enthalpies of hydrated surfaces are 0.8 ± 0.1 J/m2 for 8YSZ and 1.3 ± 0.1 J/m2 for 12YSZ.