ZrSiO_4纳米粉体的微波水热法合成及其合成机理

PREPARATION OF NANO-ZrSiO_4 POWDERS BY MICROWAVE-HYDROTHERMAL METHOD

以氧氯化锆和硅酸乙酯为原料,NaF为矿化剂,采用微波水热法(Microwave-Hydro-thermal,M-H)在160～200℃下制备出了高纯的硅酸锆纳米粉体,并利用X射线衍射(XRD)和扫描电镜(SEM)对所合成的硅酸锆粉体进行了研究.结果表明:微波水热可使ZrSi O4的结晶温度降低到160℃,合成时间可缩短到30 min,大大地降低了硅酸锆粉体的合成能耗.微波水热法合成的硅酸锆粉体颗粒呈圆片状,外形规则,粒度分布均匀(约为400 nm),ZrSi O4晶体尺寸小(约为20 nm).此外,结合测试分析,对纳米硅酸锆粉体的微波水热合成反应机理进行了初步探讨.

High-pure zircon powders were prepared using zirconium oxychloride and tetraethoxysilane as staring materials by the microwave-hydrothermal method at 160～200 ℃ for 30 min,NaF was added to gel as mineralizer to promote crystallization of zircon.The phase composition and mircostructure of zircon powders are identified by X-ray diffraction and SEM.The results showed that： microwave-hydrothermal method could greatly reduce the synthesis of zirconium silicate powder consumption by reducing the crystallization temperature of ZrSiO4 to 160 ℃ and the crystallization time to 30 min.Zircon powders by microwave hydrothermal synthesis are ellipsoids,the size and shape of Particle did not change much after the powders calcined at 950 ℃,the zircon crystal size reached the maximum（20 nm）.And the reaction mechanism of microwave hydrothermal synthesis of zirconium silicate was discussed.