Computational modelling techniques have been employed to investigate defects and ionic conductivity in Cd2GeO4. We show due to highly unfavourable intrinsic defect formation energies the ionic conducting ability of pristine Cd2GeO4 is extremely limited. The modelling results suggest trivalent doping on the Cd site as a viable means of promoting the formation of the oxygen interstitial defects. However, the defect cluster calculations for the first time explicitly suggest a strong association of the oxide defects to the dopant cations and tetrahedral units. Defect clustering is a complicated phenomenon and therefore not trivial to assess. In this study the trapping energies are explicitly quantified. The trends are further confirmed by molecular dynamic simulations. Despite this, the calculated diffusion coefficients do suggest an enhanced oxide ion mobility in the doped system compared to the pristine Cd2GeO4.
History
School
Science
Department
Chemistry
Published in
Physical Chemistry Chemical Physics
Citation
MCSLOY, A. ... et al, 2016. A computational study of doped olivine structured Cd2GeO4: local defect trapping of interstitial oxide ions. Physical Chemistry Chemical Physics, 18 (37), pp.26284-26290.
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Acceptance date
2016-09-02
Publication date
2016
Notes
This paper was accepted for publication in the journal Physical Chemistry Chemical Physics and the definitive published version is available at http://dx.doi.org/10.1039/C6CP05436F.