不同晶型结构纳米ZrO_2的稳定化制备

Preparation of Stable Nanosized ZrO_2 Particles with Different Crystallographic Structures

采用共沉淀法制备了室温稳定存在的不同晶型纳米ZrO2粉体,用X射线衍射(XRD)、激光拉曼散射(Raman)、N2物理吸附、透射电镜(TEM)和动态光散射技术(DLS)等手段对其晶型结构、晶粒尺寸、比表面积和粒度分布进行了表征,研究了煅烧温度和改性剂掺杂量对晶型结构的影响。结果表明,无掺杂前驱体在850℃煅烧可得到m-ZrO2纳米粉体,比表面积为35.17 m2/g,晶粒尺寸为51.3nm;煅烧温度为600℃,Y2O3掺杂量为4.5%(摩尔分数)时纳米粉体的晶型结构为t-ZrO2,比表面积为39.01 m2/g,晶粒尺寸为19.2nm;煅烧温度为600℃,Y2O3掺杂量为8.5%时可得到比表面积为46.53 m2/g,晶粒尺寸为12.7 nm的c-ZrO2纳米粉体。

The ambient-temperature stable nanosized ZrO2 particles with different crystallographic structures were prepared by codeposition method. Their crystallographic structures, grain size, specific surface area and size distribution were characterized by powder X-ray diffraction （XRD）, laser raman spectroscopy, N2 physical adsorption, transmission electron microscopy （TEM） and dynamic light scatter- ing （DLS） respectively. Therewith the effect of preparation temperature and modifier doping on the crystal- lographic structures of particles was investigated. The results show that the nanosized ZrO2 powders with- out Y203 doping calcined at 850℃ are monoclinic ZrO2 with an average grain size 51.3 nm and a specific surface area 35.17 m2/g; the powders doped with 4.5% Y2O3 （molar fraction） and calcined at 600℃ are te- tragonal ZrO2 with a specific surface area 39.01 m=/g and an average grain size 19.2 nm; the powders doped with 8.5% Y2O3 （molar fraction） and calcined at 600℃ are cubic ZrO2 with a specific surface area 46.53 m2/g and an average grain size 12.7 nm.