Low hole polaron migration barrier in lithium peroxide
We present computational evidence of polaronic hole trapping and migration in lithium peroxide (Li[subscript 2]O[subscript 2]), a material of interest in lithium-air batteries. We find that the hole forms in the π* antibonding molecular orbitals of the peroxide (O2[superscript 2−]) anion, and that t...
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| Format: | Article |
| Language: | en_US |
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American Physical Society
2012
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| Online Access: | http://hdl.handle.net/1721.1/71523 https://orcid.org/0000-0002-8162-4629 |
| _version_ | 1826201327597780992 |
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| author | Ong, Shyue Ping Mo, Yifei Ceder, Gerbrand |
| author2 | Massachusetts Institute of Technology. Department of Materials Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Materials Science and Engineering Ong, Shyue Ping Mo, Yifei Ceder, Gerbrand |
| author_sort | Ong, Shyue Ping |
| collection | MIT |
| description | We present computational evidence of polaronic hole trapping and migration in lithium peroxide (Li[subscript 2]O[subscript 2]), a material of interest in lithium-air batteries. We find that the hole forms in the π* antibonding molecular orbitals of the peroxide (O2[superscript 2−]) anion, and that this trapped hole induces significant local lattice distortion, forming a polaron. Our study finds migration barriers for the free polaron to be between 68 and 152 meV, depending on the hopping direction. This low barrier suggests that this material might not be as insulating as previously assumed, provided that the formation of carriers can be achieved. One transport limitation may arise from lithium vacancies, which we find to strongly bind to the polaron. This result, in combination with previous experimental results, suggests that electronic conductivity in this material is likely to be determined by vacancy diffusion. |
| first_indexed | 2024-09-23T11:50:10Z |
| format | Article |
| id | mit-1721.1/71523 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:50:10Z |
| publishDate | 2012 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/715232022-10-01T06:19:37Z Low hole polaron migration barrier in lithium peroxide Ong, Shyue Ping Mo, Yifei Ceder, Gerbrand Massachusetts Institute of Technology. Department of Materials Science and Engineering Ceder, Gerbrand Ong, Shyue Ping Mo, Yifei Ceder, Gerbrand We present computational evidence of polaronic hole trapping and migration in lithium peroxide (Li[subscript 2]O[subscript 2]), a material of interest in lithium-air batteries. We find that the hole forms in the π* antibonding molecular orbitals of the peroxide (O2[superscript 2−]) anion, and that this trapped hole induces significant local lattice distortion, forming a polaron. Our study finds migration barriers for the free polaron to be between 68 and 152 meV, depending on the hopping direction. This low barrier suggests that this material might not be as insulating as previously assumed, provided that the formation of carriers can be achieved. One transport limitation may arise from lithium vacancies, which we find to strongly bind to the polaron. This result, in combination with previous experimental results, suggests that electronic conductivity in this material is likely to be determined by vacancy diffusion. United States. Dept. of Energy (contract DE-FG02-96ER45571) Massachusetts Institute of Technology. Ford-MIT Alliance program United States. Dept. of Energy. Batteries for Advanced Transportation Technologies (BATT) program (contract DE-AC02-05CH11231) 2012-07-03T12:45:51Z 2012-07-03T12:45:51Z 2012-02 2012-01 Article http://purl.org/eprint/type/JournalArticle 1098-0121 1550-235X http://hdl.handle.net/1721.1/71523 Ong, Shyue, Yifei Mo, and Gerbrand Ceder. “Low Hole Polaron Migration Barrier in Lithium Peroxide.” Physical Review B 85.8 (2012). ©2012 American Physical Society https://orcid.org/0000-0002-8162-4629 en_US http://dx.doi.org/10.1103/PhysRevB.85.081105 Physical Review B Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society APS |
| spellingShingle | Ong, Shyue Ping Mo, Yifei Ceder, Gerbrand Low hole polaron migration barrier in lithium peroxide |
| title | Low hole polaron migration barrier in lithium peroxide |
| title_full | Low hole polaron migration barrier in lithium peroxide |
| title_fullStr | Low hole polaron migration barrier in lithium peroxide |
| title_full_unstemmed | Low hole polaron migration barrier in lithium peroxide |
| title_short | Low hole polaron migration barrier in lithium peroxide |
| title_sort | low hole polaron migration barrier in lithium peroxide |
| url | http://hdl.handle.net/1721.1/71523 https://orcid.org/0000-0002-8162-4629 |
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