Enhanced oxygen exchange of perovskite oxide surfaces through strain-driven chemical stabilization

Cited 77 time in webofscience Cited 0 time in scopus
  • Hit : 339
  • Download : 0
Surface cation segregation and phase separation, of strontium in particular, have been suggested to be the key reason behind the chemical instability of perovskite oxide surfaces and the corresponding performance degradation of solid oxide electrochemical cell electrodes. However, there is no well-established solution for effectively suppressing Sr-related surface instabilities. Here, we control the degree of Sr-excess at the surface of SrTi0.5Fe0.5O3-delta thin films, a model mixed conducting perovskite O-2-electrode, through lattice strain, which significantly improves the electrode surface reactivity. Combined theoretical and experimental analyses reveal that Sr cations are intrinsically under a compressive state in the SrTi0.5Fe0.5O3-delta lattice and that the Sr-O bonds are weakened by the local pressure around the Sr cation, which is the key origin of surface Sr enrichment. Based on these findings, we successfully demonstrate that when a large-sized isovalent dopant is added, Sr-excess can be remarkably alleviated, improving the chemical stability of the resulting perovskite O-2-electrodes.
Publisher
ROYAL SOC CHEMISTRY
Issue Date
2018-01
Language
English
Article Type
Article
Keywords

FUEL-CELL CATHODES; ELECTRONIC-STRUCTURE; CATION SEGREGATION; SR SEGREGATION; THIN-FILMS; PERFORMANCE; STABILITY; DEGRADATION; CHEMISTRY; KINETICS

Citation

ENERGY & ENVIRONMENTAL SCIENCE, v.11, no.1, pp.71 - 77

ISSN
1754-5692
DOI
10.1039/c7ee00770a
URI
http://hdl.handle.net/10203/240235
Appears in Collection
MS-Journal Papers(저널논문)
Files in This Item
There are no files associated with this item.
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡ Click to see webofscience_button
⊙ Cited 77 items in WoS Click to see citing articles in records_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0