Recent advances in phase composition regulation and microstructure morphology design of SiOC anodes for Li-ion batteries

Silicon oxycarbide (SiOC), as a unique class of silicon-based materials, are intensively pursued as the most promising anode materials for next-generation lithium-ion batteries owing to their large reversible capacity and relatively small volumetric expansion, which are expected to achieve effective compatibility between high performance and strong stability, garnering significant attention from both academia and industries. Despite these advantages, the lithium storage behavior of SiOC largely hinges on its phase composition and microstructure morphology. Notably, recent years have witnessed great achievements on the phase composition regulation and microstructure morphology design of SiOC anodes. This review first introduces the pros and cons of SiOC anodes, and elucidates the effects of phase composition and microstructure morphology on the lithium storage capability of SiOC anodes. Subsequently, the recent progress in phase composition regulation and microstructure morphology design of SiOC anodes are summarized in detail, focusing on precursor materials, preparation methods, phase composition, microstructure morphology and Lithium storage properties. Finally, the existing challenges of SiOC composition modulation and morphology engineering are analyzed, and the future trends are also prospected. This review offers a meaningful reference and theoretical cornerstone for the development of robust, high-performance SiOC anodes with controlled phase composition and tailored microstructure morphology for LIBs.