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Structural and textural evolution of zirconia nanocrystals induced by thermal treatment

Adamski A., Jakubus P., Sojka Z.

Materials Science Poland

2008

Vol. 26, No. 2

373--380

Nanometric tetragonal and monoclinic zirconia was synthesized from zirconyl chloride by the modified forced hydrolysis method. Phase transitions and morphological changes accompanying zirconia calcination in the temperaure range 600-1000 °C were studied by XRD, HR-TEM techniques and N2-porosimetry. Ageing of the amorphous hydrous zirconia at 100 °C for 48 h in the mother solution and its subsequent calcination at 600 °C for 6 h strongly favoured formation of single-phase tetragonal ZrO2 of the thermal stability enhanced by 250 °C. Influence of the calcination temperature on phase composition, grain size, grain boundaries and pore structure of the resultant ZrO2 material was analyzed.

Synthesis of nanostructured tetragonal ZrO2 of enhanced thermal stability

Adamski A., Jakubus P., Sojka Z.

Nukleonika

2006

Vol. 51,suppl.1

27-33

Hydrous zirconia particles of nanometric dimensions were synthesized via forced hydrolysis of zirconyl chloride. Prolonged aging at 100°C in the mother liquor and subsequent calcination produced a single-phase tetragonal ZrO2 of enhanced thermal stability with the narrow size and pore distributions. The influence of the preparation conditions on the phase composition of the resultant zirconium dioxide was examined using structural (XRD, SEM/TEM) and spectroscopic (Raman) methods, supported by thermal analysis (DTA/TG, DSC) and N2-porosimetry. The nature of the parent salt, pH of the solution, the temperature of precipitation and aging, were found to be the key parameters of the successful synthesis. The sequence of mechanistic steps invoked to account for the formation of t-ZrO2 was rationalized using the concepts of zirconium aquatic chemistry.