Multilevel Gradient-Ordered Silicon Anode with Unprecedented Sodium Storage
© 2023 Wiley-VCH GmbH.
Publié dans: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 36(2024), 7 vom: 19. Feb., Seite e2310270 |
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Auteur principal: | |
Autres auteurs: | , , , , , , , , , , , |
Format: | Article en ligne |
Langue: | English |
Publié: |
2024
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Accès à la collection: | Advanced materials (Deerfield Beach, Fla.) |
Sujets: | Journal Article gradient-order structure silicon anode sodium storage mechanism sodium-ion batteries universality of electrochemical reconstruction |
Résumé: | © 2023 Wiley-VCH GmbH. While cost-effective sodium-ion batteries (SIBs) with crystalline silicon anodes promise high theoretical capacities, they perform poorly because silicon stores sodium ineffectively (capacity <40 mAh g-1 ). To address this issue, herein an atomic-order structural-design tactic is adopted for obtaining unique multilevel gradient-ordered silicon (MGO-Si) by simple electrochemical reconstruction. In situ-formed short-range-, medium-range-, and long-range-ordered structures construct a stable MGO-Si, which contributes to favorable Na-Si interaction and fast ion diffusion channels. These characteristics afford a high reversible capacity (352.7 mAh g-1 at 50 mA g-1 ) and stable cycling performance (95.2% capacity retention after 4000 cycles), exhibiting record values among those reported for pure silicon electrodes. Sodium storage of MGO-Si involves an adsorption-intercalation mechanism, and a stepwise construction strategy of gradient-ordered structure further improves the specific capacity (339.5 mAh g-1 at 100 mA g-1 ). Reconstructed Si/C composites show a high reversible capacity of 449.5 mAh g-1 , significantly better than most carbonaceous anodes. The universality of this design principle is demonstrated for other inert or low-capacity materials (micro-Si, SiO2 , SiC, graphite, and TiO2 ), boosting their capacities by 1.5-6 times that of pristine materials, thereby providing new solutions to facilitate sodium storage capability for better-performing battery designs |
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Description: | Date Revised 15.02.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1521-4095 |
DOI: | 10.1002/adma.202310270 |