Engineering the biomass-derived carbon/rGO dual-modified nano‑silicon composite for high-performance lithium-ion battery anodes

Silicon's potential as a lithium-ion battery anode material is greatly constrained by its pronounced volume changes during cycling and inherently poor electrical conductivity. Although strategies like nanosizing silicon particles and applying carbon coatings offer partial improvements, fundamental issues including particle agglomeration and structural degradation during operation remain unresolved. In this study, leveraging the synergistic interplay between gelatin (GE) and sodium alginate (SA), we engineered a nitrogen-doped Si@rGO@GS via a seamlessly integrated route of liquid-phase synthesis, electrostatic self-assembly, freeze-drying, and thermal annealing. Silicon nanoparticles (Si NPs) were uniformly embedded within a hierarchically porous, three-dimensional nitrogen-doped carbon framework. The Si@rGO@GS composite electrode demonstrated superior electrochemical performance: achieving a maximum specific capacity of 1851 mAh g −1 at 0.1 A g −1 and maintaining 423 mAh g −1 even at a high current density of 2 A g −1 . Additionally, after 100 cycles at 1 A g −1 , the composite retained a reversible capacity of 548 mAh g −1 with an impressive capacity retention rate of 78.8 %. The cooperative interaction between rGO and biomass-derived carbon suppressed particle agglomeration and stabilized the carbon‑silicon interface, positioning the composite as a highly promising anode for lithium-ion batteries.