EDTA-柠檬酸络合法制备葡萄状硅酸钇纳米晶

Preparation of Grape-like Structure Yttrium Disilicate Nanocrystalline by EDTA-citric Acid Complexing Process

分别以硝酸钇(Y(NO3)3·6H2O)和正硅酸乙酯(TEOS)为起始原料,首次尝试采用乙二胺四乙酸(EDTA)-柠檬酸(CA)络合法制备合成硅酸钇(Y2Si2O7)纳米晶陶瓷粉体,研究并讨论了样品前驱体p H值和烧结温度等工艺参数对硅酸钇粉体微观形貌及其合成机理的影响。利用XRD、FE-SEM、FT-IR和TGA-DTA等分析方法对制备的样品进行了表征。结果表明,在前驱体溶胶p H值为9.38、煅烧温度为1050℃时的工艺条件下,可以得到晶粒尺寸为50 nm左右、主要组成为α-Y2Si2O7相硅酸钇粉体;粉体晶粒尺寸随烧结温度升高而增大,且粉体晶粒形貌为葡萄状的组织结构;而在前驱体溶胶p H值为4.00时,采用该方法合成的产物则是物相组成为单硅酸钇(Y2Si O5)陶瓷粉体。

Yttrium disilicate （Y2Si207） powder was attempted to synthesize using yttrium nitrate hexahydrate （Y（ NO3 ）3 · 6H2O） and tetraethyl orthosilicate （TEOS） as raw materials by EDTA-citric acid complexing process for the first time. The complexing process parameters of Y2 Si2O7 phase formation such as pH values of the precursor sol, sintering temperature and other experiment conditions were investigated. XRD, FE-SEM, FT-IR and TGA-DTA were used to characterize and analyze the samples. It was demonstrated that high-purity ot-YzSi207 powder could be obtained from the precursor sol with pH 9.38 at around 1050℃. The average crystalline size of the resulted powder was 50 nm and increased with the rising calcining temperature. The morphology of obtained α-Y2Si2O7 powders presents well- ordered and grape-like structure. At the same time, the similar synthesis method other than the pH value （ pH 4.00 in this work） can result in the formation of yttrium monosilicate （ Y2 SiO5 ） phase.