Tailoring thermal stability of ceria-zirconia mixed oxide by doping of rare earth elements:From theory to experiment

作     者：Zheng Zhao Xiaowei Huang Yongqi Zhang Juanyu Yang Meisheng Cui Yongke Hou Zongyu Feng Zheng Zhao;Xiaowei Huang;Yongqi Zhang;Juanyu Yang;Meisheng Cui;Yongke Hou;Zongyu Feng

作者机构：National Engineering Research Center for Rare Earth MaterialsGRINM Group Corporation LimitedBeijing 100088China Griem Hi-tech Co.Ltd.Langfang 065000China Rare Earth Functional Materials(Xiong’an)Innovation Center Co.Ltd.Baoding 071700China 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2022年第40卷第8期

页      面：1272-1280页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：Project supported by China Postdoctoral Science Foundation(2020M680616) Major State Research Development Program of Hebei province(20374202D)。 

主　　题：Cerium zirconium oxides surface Thermal stability Doping Structure descriptor Rare earth metals Theory and experiment 

摘      要：Ceria-zirconia mixed oxides(CZMO)are widely used in many important catalysis fields.However,pure CZMO is known to have poor thermal stability.In this paper,a strategy was proposed to design Ce_(0.475)Zr_(0.475)M_(0.05)O_(2)(M=La,Y,Pr,Nd,Pm,Sm,Eu,Gd,Tb,Er,Lu,and,Yb)oxide surface with high thermal stability by using first-principles molecular dynamics(FPMD)simulation and experiment method.Through the structure stability analysis at different temperatures,the surface energyγas a function of R_(ion)/D_(ave)is identified as a quantitative structure descriptor for analyzing the doping effect of rare earth(RE)elements on the thermal stability of Ce_(0.475)Zr_(0.475)M_(0.05)O_(2).By doping the suitable RE,γcan be adjusted to the optimal range to enhance the thermal stability of Ce_(0.475)Zr_(0.475)M_(0.05)O_(2).With this strategy,it can be predicted that the sequence of thermal stability improvement is YLaGdNdPrPmSmEuTbErYbLu,which was further verified by our experiment results.After thermal treatment at 1100℃for 10 h,the specific surface area(SSA)of aged Y-CZ and La-CZ samples can reach 21.34 and 19.51 m~2/g,which is 63.02%and 49.04%higher than the CZMO sample without doping because the surface doping of Y and La is in favor of inhibiting the surface atoms thermal displacement.In a word,the strategy proposed in this work can be expected to provide a viable way for designing the highly efficient CZMO materials in extensive applications and promoting the usages of the high-abundance rare-earth elements Y and La.