Modeling Oxygen Ion Migration in the CeO2–ZrO2–Y2O3 Solid Solution
Modeling Oxygen Ion Migration in the CeO2–ZrO2–Y2O3 Solid Solution
复制标题
CeO2-ZrO2-Y2O3 固溶体中氧离子迁移的模拟
DOI：
10.1021/acs.jpcc.8b04361
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
J. Koettgen
中科院分区：
文献类型：
--
作者：
S. Grieshammer;Sebastian Eisele;J. Koettgen
由于有意的材料工程或无意的杂质，氧化铈中的锆掺杂会影响还原行为和缺陷迁移等材料性能。在本研究中，我们利用DFT+U计算研究了锆掺杂对钇掺杂二氧化铈电导率的影响。我们计算了包含钇和锆离子的不同跃迁环境下氧离子的迁移能，并将结果与简化的迁移能模型进行比较。小锆离子会导致晶格强烈扭曲，从而导致计算能量和建模能量之间的偏差。计算的和建模的迁移能都用于动力学蒙特卡罗模拟，以获得各种掺杂剂分数的离子电导率。我们确定了对离子电导率的三个主要影响：掺杂剂离子捕获氧空位、改变缺陷周围迁移势垒的阻挡效应以及由于......
Zirconium doping in cerium oxide, as a result of intentional material engineering or unintentional impurities, impacts material properties like reduction behavior and defect migration. In this study, we investigate the influence of zirconium doping on the conductivity of yttrium doped ceria using DFT+U calculations. We calculate the migration energies of oxygen ions for different jump environments containing yttrium and zirconium ions and compare the results to a simplified migration energy model. The small zirconium ions lead to strong distortions of the lattice, which results in deviation between calculated and modeled energies. Both the calculated and the modeled migration energies are used in kinetic Monte Carlo simulations to obtain the ionic conductivity for various dopant fractions. We identify three major influences on the ionic conductivity: the trapping of oxygen vacancies by dopant ions, the blocking effect, which alters the migration barriers around defects, and the lattice contraction due to ...