Synergistic effect induced ultrafine SnO2/graphene nanocomposite as an advanced lithium/sodium-ion batteries anode

Abstract

SnO₂/graphene materials have received extensive attention in broad applications owning to their excellent performances. However, multi-step and harsh synthetic methods with high temperatures and high pressures are major obstacles that need to be overcome. Herein a simple, low-cost, and scalable approach is proposed to construct ultrafine SnO₂/graphene nanomaterials effectively under constant pressure and at the low temperature of 80 °C for 4 h, in which ultrafine SnO₂ nanoparticles grow on graphene sheets uniformly and firmly via Sn–O–C bonding. This result depends on the synergetic effect of two reactions, the reduction of graphene oxide and formation of SnO₂ nanoparticles, which are achieved successfully. More importantly, the constructed SnO₂/graphene material exhibits excellent electrochemical properties in both lithium-ion batteries and sodium-ion batteries. As an anode material for lithium-ion batteries, it displays a high reversible capacity (1420 mA h g⁻¹ at 0.1 A g⁻¹ after 90 cycles) and good cycling life (97% at 1 A g⁻¹ after 230 cycles), whereas in sodium-ion batteries, it maintains a capacity of 1280 mA h g⁻¹ at 0.05 A g⁻¹ and 650 mA h g⁻¹ at 0.2 A g⁻¹ after 90 cycles. The proposed synthetic methodology paves the way for the effective and large scale preparation of graphene-based composites for broad applications such as energy storage, optoelectronic devices, and catalysis.