Phase Stabilization in Nanocrystalline Zirconia

摘要

Nanocrystalline as well as submicron-sized tetragonal-zirconia (ZrO₂) particles have been successfully synthesized using the sol-gel technique utilizing hydroxypropyl cellulose (HPC) as a polymeric steric stabilizer. The synthesized ZrO₂ particles are characterized using transmission electron microscopy (TEM) and x-ray diffraction (XRD) to determine the nanocrystallite size and crystal structure respectively. The ZrO₂ particles of size 200-300 nm and 15-20 nm, having tetragonal crystal structure, are obtained under the processing conditions R=5, [HPC]=0.0 g/L and R=30, [HPC]=2.0 g/L respectively. Large R-value and high HPC concentration are observed to be conducive for synthesizing nanocrystalline tetragonal ZrO₂ particles. The stabilization of metastable tetragonal phase in nanocrystalline ZrO₂ is the result of minimizing the surface energy.