High-Temperature Energy Materials Research Center, Korea Institute of Science and Technology , 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea.
Department of Materials Science and Engineering, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
ACS Appl Mater Interfaces. 2017 Dec 13;9(49):42415-42419. doi: 10.1021/acsami.7b13440. Epub 2017 Dec 4.
We explored oxygen-ion transport in highly doped CeO through density-functional theory calculations. By applying biaxial strain to 18.75 mol % CeO:Gd, we predicted the average migration-barrier energy with six different pathways, with results in good agreement with those of experiments. Additionally, we found that the migration-barrier energy could be lowered by increasing the tetrahedron volume, including the space occupied by the oxygen vacancy. Our results indicate that the tetrahedron volume can be expanded by larger codopants, as well as biaxial tensile strain. Thus, the combination of thin-film structure and codoping could offer a new approach to accelerate oxygen-ion transport.
我们通过密度泛函理论计算研究了高掺杂 CeO 中的氧离子输运。通过对 18.75 mol% CeO:Gd 施加双轴应变，我们预测了 6 条不同路径的平均迁移势垒能，结果与实验结果吻合良好。此外，我们发现迁移势垒能可以通过增加四面体体积来降低，包括氧空位占据的空间。我们的结果表明，四面体体积可以通过更大的共掺杂剂以及双轴拉伸应变来扩展。因此，薄膜结构和共掺杂的结合可能为加速氧离子输运提供一种新方法。
