High-resolution and analytical TEM investigation of metastable-tetragonal phase stabilization in undoped nanocrystalline zirconia
Abbreviated Journal Title
J. Nanosci. Nanotechnol.
nanocrystalline ZrO2; sol-gel synthesis; conventional TEM; high-resolution TEM; AEM (PEELS, EDXS); OXIDATION; CATALYSTS; DESIGN; SIZE; ZRO2; Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials; Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter
Submicron and nano-sized nanocrystalline pure zirconia (ZrO2) powders having metastable tetragonal and tetragonal-plus-monoclinic crystal structures, respectively, were synthesized using the sol-gel technique. The as-precipitated and the calcinated ZrO2 powders were analyzed for their morphology, nanocrystallite size and structures, aggregation tendency, local electronic properties, and elemental compositions by conventional and high-resolution transmission electron microscopy and field-emission analytical electron microscopy, including energy-dispersive X-ray and electron energy-loss spectroscopies. The results from this study indicate that a combination of nanocrystallite size, strain-induced grain-growth confinement, and the simultaneous presence of the monoclinic phase can lead to stabilization of the metastable tetragonal-phase in undoped ZrO2. As a result, the tetragonal phase is stabilized within ZrO2 nanocrystallites up to 100 nm in size, which is 16 times larger than the previously reported critical size of 6 nm.
Journal of Nanoscience and Nanotechnology
"High-resolution and analytical TEM investigation of metastable-tetragonal phase stabilization in undoped nanocrystalline zirconia" (2004). Faculty Bibliography 2000s. 4619.