Graphite braced Multi-scale Porous SiOC/Sn Ceramics as Novel Anode Materials for Lithium-Ion Batteries

To improve the conductivity and porosity of polymer derived SiOC ceramics, we incorporated graphite into the Sn-containing SiOC precursor (SG), thereby constructing multiscale porous architectures. The introduction of graphite has a dual effect. Firstly, it stabilizes the foam structure of the polymer, and secondly, it acts as a carbon source, promoting the carbothermal reduction of Sn oxide, releasing more gas, and leading to the formation of micropores. As a result, the specific surface area increases from 31 m² g^-1 to 68 m² g^-1. The excellent electrical conductivity of graphite and the more stable porous structure brought by the introduction of graphite enhanced the electrochemical performance of the material as an anode, enabling SG to exhibit a high specific capacity of 412.3 mA h g^-1 at 1 A g^-1 while maintaining an outstanding rate performance. Moreover, the material retains a capacity of 341.3 mA h g^-1 even after enduring 1000 cycles at a current density of 1 A g^-1, demonstrating remarkable cycling stability. The integration of polymer-derived SiOC ceramics with graphite to construct a multi-scale porous strategy paves the way for the practical use of advanced lithium-ion batteries.