Association of defects in doped non-stoichiometric ceria from first principles

被引：36

作者：

Grieshammer, Steffen ^{[1
,2
,3
,4
,5
]}

Nakayama, Masanobu ^{[6
]}

Martin, Manfred ^{[1
,2
,3
,4
,5
]}

机构：

[1] Forschungszentrum Julich, Helmholtz Inst Munster IEK 12, Corrensstr 46, D-48149 Munster, Germany

[2] Rhein Westfal TH Aachen, Inst Phys Chem, Landoltweg 2, D-52056 Aachen, Germany

[3] Forschungszentrum Julich, JARA HPC, D-52425 Julich, Germany

[4] Rhein Westfal TH Aachen, D-52056 Aachen, Germany

[5] Forschungszentrum Julich, JARA Energy, D-52425 Julich, Germany

[6] Nagoya Inst Technol, Dept Mat Sci & Engn, Showa Ku, Gokiso Cho, Nagoya, Aichi 4668555, Japan

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2016年 / 18卷 / 05期

基金：

日本学术振兴会;

关键词：

CHEMICAL EXPANSION; OXYGEN NONSTOICHIOMETRY; PHASE RELATIONSHIPS; MIXED OXIDES; MONTE-CARLO; PLUS U; 1ST-PRINCIPLES; CONDUCTIVITY; TEMPERATURES; SURFACE;

D O I：

10.1039/c5cp07537h

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

We investigate the interaction and distribution of defects in doped non-stoichometric ceria Ce1-xRExO2-x/2-delta (with RE = Lu, Y, Gd, Sm, Nd, and La) by combining DFT+U calculations and Monte Carlo simulations. The concentrated solution of defects in ceria is described by the pair interactions of dopant ions, oxygen vacancies, and small polarons. The calculated interaction energies for polarons and oxygen vacancies are in agreement with experimental results and previously reported calculations. Simulations reveal that in thermodynamic equilibrium the configurational energy decreases with increasing non-stoichiometry as well as increasing dopant fraction similar to the observed behavior of the enthalpy of reduction in experiments. This effect is attributed to the attractive interaction of oxygen vacancies with polarons and dopant ions.

引用

页码：3804 / 3811

页数：8

共 44 条

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