Weakly-agglomerated nanocrystalline (ZrO2)0.9(Yb2O3)0.1 powders hydrothermally synthesized at low temperature

Nanocrystalline ytterbia (10 mol%)-doped cubic zirconia powders were synthesized by hydrothermal treatment of either an amorphous co-precipitate of hydrated ytterbia–zirconia or of zirconia xerogel in mixture with crystalline Yb2O3. The treatments were performed at 110 °C in the presence of diluted (0.2 M) or concentrated (2.0 M) solution of (K2CO3 + KOH) mineralizer and for different reaction times. The reaction times for the full crystallization of cubic-YbSZ-based products were determined for both the employed precursors and for each mineralizer solution. The various fully crystallized products were characterized in their degree of agglomeration and sintered at 1500 °C for 2 h. The best performance on sintering was achieved with the less agglomerated powder synthesized from the mechanical mixture and in the presence of the diluted solution of the mineralizer. The resulting density was the highest achieved with materials having the same composition