Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface
The recently reported fast oxygen reduction kinetics at the interface of (La,Sr)CoO3−δ (LSC113) and (La,Sr)2CoO4+δ (LSC214) phases opened up new questions for the potential role of dissimilar interfaces in advanced cathodes for solid oxide fuel cells (SOFCs). Using first-principles based calculation...
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| Format: | Article |
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Royal Society of Chemistry
2014
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| Online Access: | http://hdl.handle.net/1721.1/86188 https://orcid.org/0000-0002-2688-5666 |
| _version_ | 1826205918143971328 |
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| author | Han, Jeong Woo Yildiz, Bilge |
| author2 | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Han, Jeong Woo Yildiz, Bilge |
| author_sort | Han, Jeong Woo |
| collection | MIT |
| description | The recently reported fast oxygen reduction kinetics at the interface of (La,Sr)CoO3−δ (LSC113) and (La,Sr)2CoO4+δ (LSC214) phases opened up new questions for the potential role of dissimilar interfaces in advanced cathodes for solid oxide fuel cells (SOFCs). Using first-principles based calculations in the framework of density functional theory, we quantitatively probed the possible mechanisms that govern the oxygen reduction activity enhancement at this hetero-interface as a model system. Our findings show that both the strongly anisotropic oxygen incorporation kinetics on the LSC214 and the lattice strain in the vicinity of the interface are important contributors to such enhancement. The LSC214(100) surface exposed to the ambient at the LSC113/LSC214 interface facilitates oxygen incorporation because the oxygen molecules very favorably adsorb onto it compared to the LSC214(001) and LSC113(001) surfaces, providing a large source term for oxygen incorporation. Lattice strain field present near the hetero-interface accelerates oxygen incorporation kinetics especially on the LSC113(001) surface. At 500 °C, 4 × 102 times faster oxygen incorporation kinetics are predicted in the vicinity of the LSC113/LSC214 hetero-interface with 50% Sr-doped LSC214 compared to that on the single phase LSC113(001) surface. Contributions from both the anisotropy and the local strain effects are of comparable magnitude. The insights obtained in this work suggest that hetero-structures, which have a large area of (100) surfaces and smaller thickness in the [001] direction of the Ruddlesden–Popper phases, and larger tensile strain near the interface would be promising for high-performance cathodes. |
| first_indexed | 2024-09-23T13:21:24Z |
| format | Article |
| id | mit-1721.1/86188 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:21:24Z |
| publishDate | 2014 |
| publisher | Royal Society of Chemistry |
| record_format | dspace |
| spelling | mit-1721.1/861882022-09-28T13:35:23Z Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface Han, Jeong Woo Yildiz, Bilge Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Massachusetts Institute of Technology. Laboratory for Electrochemical Interfaces Yildiz Bilge Han, Jeong Woo Yildiz, Bilge The recently reported fast oxygen reduction kinetics at the interface of (La,Sr)CoO3−δ (LSC113) and (La,Sr)2CoO4+δ (LSC214) phases opened up new questions for the potential role of dissimilar interfaces in advanced cathodes for solid oxide fuel cells (SOFCs). Using first-principles based calculations in the framework of density functional theory, we quantitatively probed the possible mechanisms that govern the oxygen reduction activity enhancement at this hetero-interface as a model system. Our findings show that both the strongly anisotropic oxygen incorporation kinetics on the LSC214 and the lattice strain in the vicinity of the interface are important contributors to such enhancement. The LSC214(100) surface exposed to the ambient at the LSC113/LSC214 interface facilitates oxygen incorporation because the oxygen molecules very favorably adsorb onto it compared to the LSC214(001) and LSC113(001) surfaces, providing a large source term for oxygen incorporation. Lattice strain field present near the hetero-interface accelerates oxygen incorporation kinetics especially on the LSC113(001) surface. At 500 °C, 4 × 102 times faster oxygen incorporation kinetics are predicted in the vicinity of the LSC113/LSC214 hetero-interface with 50% Sr-doped LSC214 compared to that on the single phase LSC113(001) surface. Contributions from both the anisotropy and the local strain effects are of comparable magnitude. The insights obtained in this work suggest that hetero-structures, which have a large area of (100) surfaces and smaller thickness in the [001] direction of the Ruddlesden–Popper phases, and larger tensile strain near the interface would be promising for high-performance cathodes. 2014-04-16T20:21:37Z 2014-04-16T20:21:37Z 2012-05 2011-12 Article http://purl.org/eprint/type/JournalArticle 1754-5692 1754-5706 http://hdl.handle.net/1721.1/86188 Han, Jeong Woo, and Bilge Yildiz. “Mechanism for Enhanced Oxygen Reduction Kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ Hetero-Interface.” Energy & Environmental Science 5, no. 9 (2012): 8598. https://orcid.org/0000-0002-2688-5666 en_US http://dx.doi.org/10.1039/c2ee03592h Energy & Environmental Science Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Royal Society of Chemistry Prof. Yildiz via Chris Sherratt |
| spellingShingle | Han, Jeong Woo Yildiz, Bilge Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title | Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title_full | Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title_fullStr | Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title_full_unstemmed | Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title_short | Mechanism for enhanced oxygen reduction kinetics at the (La,Sr)CoO3−δ/(La,Sr)2CoO4+δ hetero-interface |
| title_sort | mechanism for enhanced oxygen reduction kinetics at the la sr coo3 δ la sr 2coo4 δ hetero interface |
| url | http://hdl.handle.net/1721.1/86188 https://orcid.org/0000-0002-2688-5666 |
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