RuO2-CeO2复合氧化物相分离现象与本质的分析  

Analysis on phase-decomposition in RuO2-CeO2 complex oxides and its nature

作　　者：王欣[1,2,3] 王虎[1,3] 唐中帜 周扬杰[2] 唐电 WANG Xin;WANG Hu;TANG Zhongzhi;ZHOU Yangjie;TANG Dian(College of Material Science and Engineering, Fuzhou University, Fuzhou 350108, China;Institute of Materials Research, Fuzhou University, Fuzhou 350108, China;Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou 350002, China)

机构地区：[1]福州大学材料科学与工程学院,福建福州350108 [2]福州大学材料研究所,福建福州350108 [3]中国科学院功能纳米结构设计与组装重点实验室,福建福州350002

出　　处：《福建工程学院学报》2020年第6期535-542,共8页Journal of Fujian University of Technology

基　　金：国家自然科学基金资助项目(11374053,11104031);福建省自然科学基金资助项目(2019J01640);福建省教育厅高校专项基金资助项目(JK2017005)。

摘　　要：采用基于密度泛函(DFT)第一性原理的计算方法,获得金红石和萤石相Ru(1-x)CexO2固溶体的能量和结构数据,分析了固溶体的分离能、混合吉布斯自由能和热力学状态图,指出在常规热分解温度(723 K)下,固溶体存在spinodal分解为RuO2+CeO2的倾向,并对723 K热分解制备高、中、低Ru含量的Ru(1-x)CexO2样品进行了XRD分析,发现Ru(1-x)CexO2更倾向于遵循qusia-spinodal机制分解为RuO2R+CeO2F。文章从体系自由能的角度初步讨论了Ru(1-x)CexO2发生qusia-spinodal的反应机制。Total energies and lattice structures of rutile and fluorite solid solution Ru(1-x)CexO2 were calculated by DFT first principles scalculation method.The separating energies,mixing free energies and thermodynamic phase-diagrams of Ru(1-x)CexO2 were investigated.It was indicated that the Ru(1-x)CexO2 separates spinodally into RuO2 and CeO2 at 723 K.The XRD examination was verified that Ru(1-x)CexO2 inclines to decompose qusia-spinodally into RuO2R+CeO2F,using high,medium and low-concentration ruthenium(1-x)RuO2-xCeO2 samples,which were prepared at 723 K by thermal decomposition method.The mechanism of qusia-spinodal reaction of Ru(1-x)CexO2 was discussed preliminarily based on the system free-energy.

关 键 词：第一性原理 Ru(1-x)CexO2 相互作用系数 spinodal分解曲线 

分 类 号：TQ460.64[化学工程—制药化工]