聚乙二醇水热法制备锆酸镧纳米晶

Nanostructured Lanthanum Zirconate Prepared by Polyethylene Glycol Hydrothermal Method

摘要: 文中采用聚乙二醇水热法液相合成的方法，探讨了在较低温度下合成La₂Zr₂O₇纳米晶为主体粉末的工艺，并对已获得的La₂Zr₂O₇粉末进行了结构的表征。结果表明，采用K₂CO₃作为矿化剂，在225˚C进行La₂Zr₂O₇合成反应，并不能一步生成La₂Zr₂O₇纳米晶体，而只能生成LaCO₃(OH)的前驱体，但是当对该前驱体进行二次烧结后，即可以获得以La₂Zr₂O₇为主体的纳米晶，在900˚C~1100˚C条件下烧结的La₂Zr₂O₇晶粒尺寸小于30 nm，即使在1400˚C条件下烧结2 h，La₂Zr₂O₇晶粒尺寸也仅60 nm。

Abstract: Nanostructured lanthanum zirconate powders were successfully prepared by polyethylene glycol hydrothermal method at relatively lower sintering temperature. XRD and SEM were carried out to study the phase structure and grain size of the lanthanum zirconate. It can be concluded that precursor of lanthanum zirconate can be obtained after hydrothermal synthesis at 498 K and nanostructured lanthanum zirconate can be obtained after sintered at high temperature (above 1173 K). The grain size of lanthanum zirconate is about 30 nm after sintered at 1173 K - 1373 K. Meanwhile, the grain size is as small as 60 nm after sintered at 1673 K for 2 h.