Si‐Rich SiOC–rGO Composites as Advanced Anodes for Lithium‐Ion Batteries

Silicon oxycarbide (SiOC) has emerged as a promising anode material for next‐generation lithium‐ion batteries owing to its structural stability and ability to accommodate large amounts of lithium. However, its practical application is often limited by insufficient electronic conductivity and poor electrochemical utilization of active silicon‐rich domains, particularly under high‐rate operation. In this work, we report a surface‐engineering strategy in which synthesized silicon‐rich SiOC is integrated with chemically modified reduced graphene oxide (rGO) through a facile freeze‐drying process to construct a highly conductive Si‐rich SiOC‐rGO composite anode. The achieved electrochemical performance surpasses that of many previously reported doped SiOC anodes, highlighting surface‐engineered silicon‐rich SiOC‐rGO composites as an attractive alternative to more complex compositional modification strategies. The interconnected rGO network enhances electronic transport, facilitates charge‐transfer kinetics, and promotes efficient utilization of the active silicon‐rich phase while maintaining the structural integrity of the SiOC matrix during repeated lithiation/delithiation. As a result, the SiOC‐rGO composite delivers substantially improved electrochemical performance compared with pristine Si‐rich SiOC, exhibiting high reversible specific capacity, excellent rate capability, and remarkable long‐term cycling stability. Notably, the composite retains a capacity of ~600 mAh g −1 at a high rate of 2 C after 1000 cycles, demonstrating outstanding durability under demanding operating conditions.