Abstract

Zirconia powders with nano size pores and high specific surface areas were synthesized via aqueous precipitation and hydrothermal synthetic method using ZrOCl_28H_2O and NH_4OH under pH=11 and ambient condition. By this reaction. zirconia hydrate (ZrO_x(OH)_4-2x) was primarily synthesized and the obtained zirconia hydrate was heat treated hydrothermally using an autoclave at various temperatures under pH=11. X-ray diffraction, Scanning electron microscopy, Energy dispersive X-ray spectroscopy, FT-IR, Raman, Particle size analysis, DTA-TG, and BET techniques were used for the characterization of the powder. The synthesized zirconia showed an amorphous phase, however, the phase was transformed to the crystalline state during the hydrothermal process. The observed crystalline phase above 160°C was a mixed phase of monoclinic and tetragonal zirconia. By the BET analysis, it was found that the specific surface area was ranged in 126sim276m2/g and the zirconia had the cylindrical shaped pores with average diameter of 2sim7nm.

• Keywords: Nanoporous;Zirconia;Hydrothermal synthesis;