Doped apatites for novel solid oxide fuel cell applications

Ow, Jia Wei Nicholas Earvin and Musso, Federico and Bertuzzo, Marcus and Alfredsson, Maria and Corà, Furio (2015) Doped apatites for novel solid oxide fuel cell applications. In: ECS Conference on Electrochemical Energy Conversion & Storage with SOFC-XIV - 14th International Symposium on Solid Oxide Fuel Cells, SOFC 2015, 26 July 2015 - 31 July 2015, Glasgow, Scotland. (doi:https://doi.org/10.1149/06801.0529ecst) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

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Official URL
http://dx.doi.org/10.1149/06801.0529ecst

Abstract

The aim of this study is to gain insight into the local coordination of doped apatites (e.g. La8Y2Ge6O27) using the GULP (General Utility Lattice Program) code. Apatite ceramics are believed to facilitate oxygen conduction by rearranging its local structure in the presence of oxygen excess. By understanding the oxygen conduction mechanism we can design materials with improved functionality. The objectives of this study are twofold: firstly, to investigate the energetics of doping in the Ge apatites and secondly, to further investigate the interstitial-oxide migration pathway and energy barriers involved in the migration. It has been found that isovalent doping with ions of smaller ionic radii than Ge4+, e.g. Si4+ and Ti4+, are favourable, as is hypervalent doping on the Sr site, leading to an oxide ion excess in the structure. The excess oxide ion migration pathway takes place via a wheel mechanism with an energy barrier of 0.66 eV. This mechanism is different from the one proposed in Si-based apatites, which is done by a sinusoidal trajectory. © The Electrochemical Society.

Item Type: Conference or workshop item (Proceeding)
Additional information: cited By 0; Conference Code:113202
Uncontrolled keywords: Apatite; Energy barriers; Fuel cells; Fuel storage; Germanium; Ions; Oxygen; Phosphate minerals; Titanium oxides; Utility programs, Apatite ceramics; Excess oxide ion; Local coordination; Local structure; Migration pathway; Oxygen conduction; Sinusoidal trajectories; Wheel mechanism, Solid oxide fuel cells (SOFC)
Subjects: Q Science > QD Chemistry
Divisions: Faculties > Sciences > School of Physical Sciences > Functional Materials Group
Depositing User: Giles Tarver
Date Deposited: 12 Jan 2016 11:10 UTC
Last Modified: 14 Jan 2016 09:49 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/53688 (The current URI for this page, for reference purposes)
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