Engineering graphene oxide modified SnS/Sn-SiO_x/C composite anode for ultrastable lithium-ion batteries

The development of high-performance anode materials is critical for progressing lithium-ion battery (LIB) technology. In spite of the fact that SiO_x has gained prevalent attention due to its high theoretical capacity and low cost, its practical application is impeded by poor electrical conductivity, severe volume expansion and unstable solid electrolyte interface (SEI) formation. In this work, a novel GO-SnS/Sn-SiO_x/C composite was synthesized via sol-gel, co-precipitation and loading approaches. The integration of SnS/Sn improved electronic conductivity and capacity; yet, its high reactivity led to continuous electrolyte decomposition. To constrain the inherent challenges associated with SiO_x and SnS/Sn, graphene oxide (GO) was employed as a flexible conductive matrix to uniformly disperse SnS/Sn particles and buffer mechanical stress during cycling. The GO-SnS/Sn-SiO_x/C composite exhibited superior electrochemical performance, delivering enhanced specific capacity, outstanding rate capability and remarkable long-term cycling stability compared to both bare SiO_x/C and SnS/Sn-SiO_x/C electrodes. The findings indicated that as-prepared nanohybrid GO-SnS/Sn-SiO_x/C released a steady reversible capacity of 759.5 mAh/g with high-capacity retention of 80.6% at 1 A/g after 500 cycles, surpassing SiO_x/C (56.3 mAh/g) and SnS/Sn-SiO_x/C (96.3 mAh/g) anodes by factors of 13.5 and 7.9, respectively. The reduced charge-transfer resistance and improved lithium-ion diffusion were ascribed to this exceptional enhancement. This tactic paves the path for the advancement of hybridized SiO_x anode materials with extended cycle life and excellent processability for high-capacity LIBs.