Effects of H_2O_2 and SO~2-_4 species on the crystalline structure and surface properties of ZrO_2 processed by alkaline precipitation

摘要

The preparation of ZrO_2 by alkaline hydrolysis of ZrOCl_2 . 8H_2o, leads to an amorphous oxohydroxide precursor that upon calcinations at temperatures higher than 350 deg C produces s system with mixed crystallographic phases (monoclinic and tetragonal). Preparation of this material by the same procedure but adding different molar ratios of H_2O_2 produces amorphous precursors (ZHPn) developing, mainly, the tetragonal crystal phase at the same calcinations temperatures.