Sn/Sn4P3/RGO Composite with Enhanced Structural Integrity as Durable Anode Material for Lithium-Ion Batteries

Sn-based materials have attracted extensive attention in the research of anode materials for lithium-ion batteries (LIBs) due to their high theoretical specific capacity. Nevertheless, severe volume expansion and rapid capacity decay occur in Sn-based materials during the charge–discharge process, which greatly restrict their practical application. To circumvent the above issues, a tin-based phosphide composite (Sn/Sn4P3/RGO) is synthesized by freeze-drying combined with solid-phase phosphorization. Benefiting from the unique three-dimensional graphene encapsulation structure and Sn–Sn4P3 synergistic heterostructure, the as-prepared Sn/Sn4P3/RGO nanocomposite enhances electrical conductivity and alleviates the volume expansion of electrodes. The multiphase hybridization of Sn and Sn4P3 increases the number of active sites, thereby endowing the electrode with superior specific capacity. In summary, when utilized as anode for LIBs, the Sn/Sn4P3/RGO composite delivers a reversible capacity of 1125 mAh g–1 after 200 cycles at a current density of 0.5 A g–1. Moreover, it maintains capacities of 676.2 mAh g–1 and 388.2 mAh g–1 after 1000 cycles at 2.0 A g–1 and 5.0 A g–1, respectively. This work provides a strategy for the preparation of high-performance tin-based anode materials for lithium-ion batteries.