Tetragonal Nanophase Stabilization in Nondoped Sol–Gel Zirconia Prepared with Different Hydrolysis Catalysts

Solid Solutions of WO3into Zirconia in WO3–ZrO2 Catalysts

“…Both, the fact that the X-ray diffraction patterns (Fig. 1) were similar to those of tetragonal zirconia (22,23) and that tungsten was in the samples clearly evidence that zirconia and tungsten oxide formed solid solutions. If that were not the case, other phases related with so large amounts of tungsten oxide would appear in the diffraction patterns, and the tetragonal phase would not be stable at so large annealing temperatures.…”

Synthesis and Room‐Temperature Ultraviolet Photoluminescence Properties of Zirconia Nanowires

“…The crystalline zirconia size of 30 nm or less is now believed to stabilize the tetragonal form at room temperature due to the contribution of surface energy [34] and size effects. [35] We attribute the existence of metastable t-ZrO 2 nanowires at room temperature to the contribution of the suitable starting materialsÐzirconium salt and gel-derived zirconia.…”

Fine tuning of the sizes and phases of ZrO2 nanocrystals

“…Since it is recognized that well crystallized nanocrystals will lead to improved mechanical, chemical, and catalytic properties [22 24], various methods have been developed to synthesize zirconia nanocrystals, including hydrothermal synthesis [25], sol-gel synthesis [26], spray pyrolysis [27], mechanochemical processing [28], and twophase synthesis [29]. Most of these products suffer from broad particle size distributions and severe aggregation, however.…”