添加稀土Gd的氧化锆的物相分析

Phase analysis of rare earth Gd doping ZrO_2

以硝酸锆、硝酸钆和柠檬酸为原料,按n(Gd)∶n(Zr)分别为1∶993、∶97、5∶95、8∶92和10∶90的配比在1 200℃煅烧6 h制备了稀土Gd掺杂ZrO2试样,以研究Gd与ZrO2的化学相容性;进而按n(Gd2Zr2O7)∶n(ZrO2)分别为1∶10、1∶8、1∶41、∶21、∶1、4∶1和8∶1的配比于1 200℃煅烧6 h原位合成了Gd2Zr2O7-ZrO2复合材料。采用XRD和拉曼光谱研究了稀土Gd掺杂ZrO2和Gd2Zr2O7-ZrO2复合材料的物相组成和结构。结果表明:稀土Gd容易进入ZrO2晶格形成固溶体,当稀土Gd掺杂量较少时,随着稀土Gd掺杂量的增加,m-ZrO2逐渐转变为t-ZrO2;当稀土Gd添加量较多时,随着Gd量的增加,逐渐原位生成了萤石结构的稀土锆酸盐Gd2Zr2O7,从而合成了由Gd2Zr2O7和t-ZrO2构成的Gd2Zr2O7-ZrO2复合材料。

Rare earth Gd doping ZrO2 specimens were prepared using Zr（NO3）4·3H2O,Gd（NO3）3·6H2O and C6H8O7·H2O as starting materials according to the molar ratio of Gd and Zr（1∶99,3∶97,5∶95,8∶92,10∶90） and firing at 1 200 ℃ for 6 h for studying chemical compatibility of Gd and ZrO2,and then Gd2Zr2O7-ZrO2 composites were in-situ fired at 1 200 ℃ for 6 h according to the molar ratio of Gd2Zr2O7 and ZrO2（1∶10,1∶8,1∶4,1∶2,1∶1,4∶1,8∶1）.The phase composition and structure of the composites were studied by XRD and Raman.The results indicate that it is easy for Gd to enter crystal lattice of ZrO2 forming solid solution;when the doping amount of Gd is less,the m-ZrO2 transforms into t-ZrO2 with the increase of doping amount of Gd;when the doping amount of Gd is more,the fluorite-structured Gd2Zr2O7 forms gradually with the increase of doping amount of Gd,so the Gd2Zr2O7-ZrO2 composite composed of fluorite-structured Gd2Zr2O7 and t-ZrO2 is synthesized.