Interface-engineered 2D Si-graphene oxide composite anodes for enhanced Li-ion storage performance

Abstract

Two-dimensional (2D) silicon (Si) and reduced graphene oxide (rGO)-based composites have emerged as promising anode materials for next-generation lithium-ion batteries (LIBs) due to their high specific capacity, mechanical flexibility during cycling, and cost-effective scalability. However, their practical application is still limited by challenges such as material agglomeration and weak interfacial bonding between Si and rGO. In this study, we address these limitations by engineering a 2D Si anode with an interlayer interface structure. This is achieved through the electrostatic self-assembly of siloxene and GO, followed by magnesiothermic reduction. The resulting composite features stable and efficient interfacial connections, which significantly improve both cycling stability and rate performance compared to conventional 2D Si-based anodes. The optimized anode delivers a high specific capacity of 1518 mAh g^–1 with an initial Coulombic efficiency of 79.8% at 100 mA g^–1, along with superior rate capability. Notably, it retains a high specific capacity of 1097 mAh g^–1 at 1 A g^–1, coupled with improved Coulombic efficiency. These findings offer a promising pathway for the rational design of Si-based anode materials, advancing the development of high-energy, high-power LIBs.