Performance-optimized diatom-SiOx anodes for Li-ion batteries by preserving the nanostructured SiO2 shells of diatom microalgae and tailoring oxygen content
Nanostructured silicon oxides (SiO) are close-to-market anode materials for increasing the energy density of next-generation lithium-ion batteries (LIBs), offering a balance between high capacity and enhanced cycling stability. However, achieving precise control over SiO composition while maintainin...
| Autores: | , , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/390162 |
| Acceso en línea: | http://hdl.handle.net/10261/390162 |
| Access Level: | acceso abierto |
| Palabra clave: | Diatom Li-ion battery SiOx Anode Sustainability |
| Sumario: | Nanostructured silicon oxides (SiO) are close-to-market anode materials for increasing the energy density of next-generation lithium-ion batteries (LIBs), offering a balance between high capacity and enhanced cycling stability. However, achieving precise control over SiO composition while maintaining structural integrity remains a challenge. In this study, we pioneer the use of nanostructured diatom-SiO2 frustules from industrially cultured Nitzschia sp. microalgae as a sustainable and tunable precursor for high-performance SiO anodes via scalable magnesiothermic reduction reaction (MgTR). By optimizing the Mg-to-diatom-SiO2 molar ratio, we demonstrate controlled partial reduction of SiO2, yielding Si nanocrystals embedded within an SiO2 matrix. Notably, we reveal that the preservation of diatom-SiO nanoporosity is highly sensitive to reaction exothermic conditions and is effectively stabilized by introducing NaCl as a heat scavenger. Tailoring the reactant composition (SiO2:Mg:NaCl = 1:1:2.5) resulted in anodes with superior electrochemical performance, delivering high capacity retention over 200 cycles. Through a comprehensive suite of characterization techniques, we establish the structure–property-performance relationships governing SiO anode behavior. These findings mark a major advancement in sustainable SiO anode design, providing a scalable strategy for integrating biologically templated nanostructures into high-performance LIBs. |
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