Author(s) |
Khan, Saba
Kumar, Narender
Hussain, Tanveer
Tit, Nacir
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Publication Date |
2023-10-01
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Abstract |
<p>Sodium-sulfur batteries show great potential for storing large amounts of energy due to their ability to undergo a double electron-redox process, as well as the plentiful abundance of sodium and sulfur resources. However, the shuttle effect caused by intermediate sodium polysulfides (Na<sub>2</sub>S<sub>n</sub>) limits their performance and lifespan. To address this issue, here we propose using Hf<sub>3</sub>C<sub>2</sub>T<sub>2</sub> and Zr<sub>3</sub>C<sub>2</sub>T<sub>2</sub> (T = F, O), two functionalized MXenes, as cathode additives to suppress the shuttle effect. By using density-functional theory calculations, we investigate nature of the interactions between Na<sub>2</sub>S<sub>n</sub> and MXene, such as the strength of adsorption energy, the electronic density of states, the charge exchange, and the dissociation energy of the Na<sub>2</sub>S molecule. Our findings show that both Hf<sub>3</sub>C<sub>2</sub>T<sub>2</sub> and Zr<sub>3</sub>C<sub>2</sub>T<sub>2</sub> systems inhibit the shuttle effect by binding to Na<sub>2</sub>S<sub>n</sub> with a binding energy stronger than the commonly used electrolyte solvents. These MXenes retain their metallicity during this process and the decomposition barrier for Na<sub>2</sub>S<sub>n</sub> on the oxygen-functionalized MXenes gets reduced which enhances the electrochemical process. Among the MXene systems studied, Zr<sub>3</sub>C<sub>2</sub>T<sub>2</sub> shows the best performance in suppressing the shuttle effect and catalyzing the electrochemistry process and, thus, increasing the battery's reversible capacity and lifespan.</p>
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Citation |
Journal of Power Sources, v.580, p. 1-11
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ISSN |
1873-2755
0378-7753
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Link | |
Publisher |
Elsevier BV
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Rights |
Attribution 4.0 International
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Title |
Functionalized Hf3C2 and Zr3C2 MXenes for suppression of shuttle effect to enhance the performance of sodium–sulfur batteries
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Type of document |
Journal Article
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Entity Type |
Publication
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Name | Size | format | Description | Link |
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openpublished/FunctionalizedHussain2023JournalArticle.pdf | 14918.955 KB | application/pdf | Published Version | View document |