A facile approach to the synthesis of non-porous and microporous sub-micron spherical zirconia and alumina–zirconia solid solution

Amorphous monodisperse sub-micron spherical zirconia and alumina/zirconia solid solution particles were prepared by hydrolysis of zirconium and aluminum salts in ethanol. The heat-treatment process of the amorphous materials in air atmosphere at 500 °C for 2 h leaded to the production of non-porous zirconia and alumina/zirconia solid solution in tetragonal phase. The alkaline etching process of the as-prepared alumina/zirconia solid solution resulted in the formation of mono-modal microporous material with specific surface area of 125.0 m2 g−1 in comparison with 2.9 m2 g−1 for the parent material. Thermal analysis of the solid solution revealed that the incorporation of aluminum ions in the zirconia structure has decreased the phase transformation temperature from amorphous to crystalline structure. Moreover, optical study confirmed the presence of oxygen vacancy defect by substitution of tetravalent cations, Zr4+ by trivalent cations, Al3+ in zirconia lattice.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (108 K)Download as PowerPoint slideHighlights► Sub-micron, non-porous, and spherical zirconia was prepared by a new method. ► The method could also be used to produce alumina/zirconia solid solution (40% Al). ► Mono-modal microporous material was obtained by alkaline etching of solid solution. ► The microporous material has 125.0 m2 g−1 surface area and 1 nm mean pore diameter. ► The method can allow us to produce other solid solutions.