低pH值条件下纤维状ZrO_2水合物的制备及其形成机理研究

Preparation and Formation Mechanism of Fibrous Hydrous Zirconia at Low pH Values

以无机盐氧氯化锆(ZrOCl2·8H2O)为原料,H2O2为水解促进剂,乙醇为溶剂,低pH值条件下制备了纤维状ZrO2水合物．运用FT-IR、TG、XRD研究了ZrO2水合物的组成、结构和热稳定性,用光学显微镜、FESEM对ZrO2水合物的形貌及其形成机理进行了分析．结果表明,ZrO2水合物分子简式为Zr(μ-OH)2(OH)2·2H2O;经80℃干燥的ZrO2水合物为非晶态,随热处理温度的升高,物相结构由亚稳四方相向单斜相转变;ZrO2水合物是由尺寸较小的短纤维通过表面羟基的氢键作用,按一定方式聚集而成的尺寸较大的纤维簇．

Hydrous zirconia was prepared at low pH values with ZrOCI2-8H2O as raw material, H2O2 as hydrolysis promoter and ethanol as solvent. FT-IR, TG and XRD were applied to study the components, structure and heat-stabilization of hydrous zirconia. Light microscope and FESEM were used to analyze the microcosmic structure of hydrous zirconia, its formation mechanism was also discussed. The results show that the molecular formula of hydrous zirconia is Zr（μ-OH）2（OH）2·2H2O. The hydrous zirconia is amorphous, and as the treating temperature rising, it will turn from metastable tetragonal phase to monoclinic phase. The hydrous zirconia is fiber cluster composed of small short fibers via hydrogen bonds.