Correlations between the Oxygen Ionic Conductivity of Sr- and Mg-doped LaGaO3 and Its Crystal Structure

DOI

10.2991/icsmim-15.2016.39How to use a DOI?

Keywords

Solid oxide fuel cells (SOFCs); Laser rapid sintering (LRS); Solid state reaction (SSR); Crystal structure; Oxygen ionic conductivity.

Abstract

Oxygen vacancy formation and migration in La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) with various crystal symmetries (cubic, orthorhombic and monoclinic) are studied by employing first-principles calculations based on density functional theory (DFT). The calculated vacancy formation energy of the cubic LSGM is 3.96 eV, much lower than those of orthorhombic and monoclinic LSGM. The calculated averaged migration energies increase in the order of . There is a clear trend towards higher migration energies as the crystal symmetry becomes lower. That is to say that the oxygen ion conductivity increases in the order of , accompanied a clear trend towards higher oxygen ion conductivity as the lattice becomes closer to the ideal cubic symmetry. The much lower formation and migration energies of oxygen vacancies in C-LSGM than in the other two structures imply the best oxygen ion conductivity of C-LSGM among the three crystal structures. The results obtained in this paper can not only elucidate the correlations between the ion conductivity and crystal structures of the LSGM, but also predict rational crystal structures of LSGM for solid oxide fuel cell applications.

Copyright

© 2016, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Jie Zhang
AU  - Ya’Nan Tang
AU  - Hairong Gao
AU  - Chenggang Li
AU  - Lijun Pan
PY  - 2016/01
DA  - 2016/01
TI  - Correlations between the Oxygen Ionic Conductivity of Sr- and Mg-doped LaGaO3 and Its Crystal Structure
BT  - Proceedings of the 2015 4th International Conference on Sensors, Measurement and Intelligent Materials
PB  - Atlantis Press
SP  - 208
EP  - 211
SN  - 2352-538X
UR  - https://doi.org/10.2991/icsmim-15.2016.39
DO  - 10.2991/icsmim-15.2016.39
ID  - Zhang2016/01
ER  -