Size Effects on the Stabilization of Ultrafine Zirconia Nanoparticles

Abstract

The spontaneous oxidation of crystallized ZrAu at room temperature leads to the formation of ultrafine monoclinic zirconia (MZ) particles (about 3.6 nm in diameter). The presence of tetragonal phase (TZ), generally observed in very small zirconia particles, was investigated by X-ray diffraction and Raman experiments but was not observed. Thermodynamical calculations considering the finite size effects in zirconia were introduced to explain the formation of pure MZ considering experimental and theoretical surface energies. The results of these calculations associated with the near equilibrium conditions used for synthesis demonstrate that the monoclinic structure is the stable crystallographic structure of zirconia nanocrystals at room temperature.

Synthesis and optical properties of yttria-doped ZrO2 nanopowders

“…It is the only transitional metal oxide that presents both acidity and alkalescence centers, along with the high performance in mechanical, thermal, optical, catalytic properties and high ionic conductivity at elevated temperatures (>1000 K) [1][2][3][4], so, ZrO 2 has been widely used in the fields of functional ceramics as well as electronic materials, oxygen sensors, humidity sensors, anode in fuel cells and catalytic membrane reactors [5][6][7][8][9].…”

Surface characteristics, corrosion resistance and MG63 osteoblast-like cells attachment behaviour of nano SiO2–ZrO2 coated 316L stainless steel

“…1. 28 The Zr-O and Zr-O-Zr bands were detected as weak signals at 583 cm À1 and 506 cm À1 respectively. Presence of peaks at about 800 cm À1 and 950 cm À1 were assigned to Si-O-Si bridge vibration and terminal -Si-OH stretching vibrations respectively.…”

Mn/Al2O3 and Mn/ZrO2 as selective catalysts for the synthesis of bis(indolyl)methanes: The role of surface acidity and particle morphology

“…We noticed in the present studies that in the case of Mn/ZrO 2 -450 the intensity of the diffraction peaks corresponding to the tetragonal phase increased where as those of monoclinic phase disappeared. The stabilization of catalytically active tetragonal phase is attributed to a decrease in the particle size of zirconia [41]. Thus, it may be inferred, the presence of manganese oxide with zirconia not only favored the stabilization of catalytically active tetragonal phase but also increased surface area as well as surface acidity, as discussed in the following sections.…”