Three-dimensional dual graphene anchors ultrafine silicon by a reinforced interface as advanced anode for lithium-ion batteries

Silicon/carbon anodes are emerging as promising candidates for the next generation of commercial lithium-ion batteries (LIBs), sparking intense research into their facile nanosized synthesis. This work presents an anode material, 3DG@Si@G, which integrates ultrafine silicon (UF-Si) within a three-dimensional graphene (3DG) structure by physical vapor deposition and is further encapsulated with graphene using chemical vapor deposition. The UF-Si particles reduce the diffusion distances for Li+ and minimize volumetric changes during cycling. The dual graphene structure is designed to synergistically facilitate efficient electron/lithium-ion (Li+) transport. Furthermore, the Si-C bonds at the interface enhance the structural stability and electrical contacts. As a result, the 3DG@Si@G composite demonstrated an outstanding reversible capacity of 1503.9 mAh g- 1 over 100 cycles at 0.2 A g- 1. Furthermore, using the 3DG@Si@G composite, 3DG@Si@G||LiFePO4 full cell demonstrated a stable reversible specific capacity of 120.5 mAh g- 1 over 100 cycles at 1A g- 1. This research contributes a viable synthetic strategy for the facile preparation of high-performance silicon/carbon anode materials.