Robust anchoring of Si-Fe nanoalloys on graphite via continuous conductive matrix for superior lithium-ion storage performance

Silicon/graphite (Si/G) composites are promising anode candidates for high-energy–density lithium-ion batteries (LIBs) due to their high theoretical capacity. However, challenges such as severe volume expansion (~ 300%) during cycling, low ionic conductivity, and weak interfacial contact between Si and graphite remain. Herein, we report a scalable synthesis of Si-Fe nanoparticles (SF NPs) via arc plasma evaporation, which are strongly anchored on graphite surfaces via liquid-phase assembly combined with phenolic resin carbonization. This configuration forms a continuous conductive network, enabling structural accommodation to volume changes and stress redistribution, thus maintaining electrical conductivity. Electrochemical evaluations revealed that SFG@HC with 20% phenolic resin additive (SFG@HC-20%) exhibits exceptional cycling stability and rate capability. After 500 cycles at 500 mA·g⁻¹, it retained 82.4% capacity retention. Notably, a discharge capacity of 705.1 mAh·g⁻¹ was achieved at 100 mA·g⁻¹, recovering to 701.9 mAh·g⁻¹ after high-rate cycling. The scalable synthesis strategy and outstanding performance establish a viable pathway for commercializing silicon-carbon composites in advanced LIBs.