原位合成 La2Zr2O7-YSZ 复合材料及高温热稳定性研究
Study on In-situ Synthesis and High Temperature Stability of La2Zr2O7-YSZ Composites
摘要:以硝酸锆、硝酸镧、硝酸钇和柠檬酸为原料,原位合成了La2Zr2O7、氧化钇稳定氧化锆(YSZ)及其La2Zr2O7-YSZ复合材料。采用X射线衍射和拉曼光谱对样品进行分析和表征,研究La2Zr2O7、YSZ和La2Zr2O7-YSZ复合材料的物相组成与高温热稳定性。结果表明:合成的La2Zr2O7和YSZ均为单一纯相。在1 200℃煅烧6 h条件下合成的系列复合材料(物质的量比n(La2Zr2O7)∶n(YSZ)=1∶810∶1)中均未发现单斜ZrO2相和其他化合物的生成。在1 400℃煅烧24 h条件下合成的LZYZ11中出现单斜ZrO2相,此时La2Zr2O7对YSZ的稳定效果不大。
关键词: 原位合成;物相组成;高温热稳定性
Abstract: La2Zr2O7, yttria-stabilized zirconia (YSZ) and La2Zr2O7-YSZ composites were synthesized by in-situ synthesis method with Zr(NO3)4· 3H2O and La(NO3)3·6H2O and Y(NOH2O·6H2O and C6H8O7·H2O as raw materials. The phase composition and high temperature stability of the products were studied by X ray diffraction(XRD) and Raman spectrum. The results indicated that La2Zr2O7 and YSZ were pure phase, there were not monoclinic ZrO2 phase and other compound in all of La2Zr2O7-YSZ calcined at 1 200 ℃ for 6 h, La2Zr2O7 and YSZ could coexist, the monoclinic ZrO2 phase was produced in YSZ and LZYZ11 by calcining at 1 400 ℃ for 24 h, it was clear that La2Zr2O7 was no conducive to the stabilizing of YSZ.
Keywords: in-situ synthesis ; phase composition ; high temperature stability