Incorporation of titanium into the inorganic wall of ordered porous zirconium oxide via direct synthesis

The ordered porous zirconium oxide incorporated with variable amounts of ti tanium was synthesized via a direct-hydrothermal synthesis procedure. Chara cterizations by powder X-ray diffraction, nitrogen adsorption, high-resolut ion transmission electron microscopy, and energy-dispersive, X-ray photoele ctron, Raman, and diffuse reflectance ultraviolet spectroscopies have been carried out to study the chemical nature of titanium in the porous ZrO2 mat erial. The results show that titanium ions are homogeneously dispersed into the framework of ZrO2, when the amount of titanium doping is less than 20 mol %, which is much higher than that in silica-based materials. At higher titanium loading, nanocrystalline TiO2 anatase is formed. A suitable amount of titanium is favorable to the thermal stability of the porous zirconium oxide.