3D graphene network encapsulating SnO2 hollow spheres as a high-performance anode material for lithium-ion batteries

Abstract

Herein, we report a reliable method for the synthesis of nanohybrids with interconnected networks of reduced graphene oxide (rGO) enwrapping hollow SnO₂ nanospheres (H-SnO₂@rGO), which is implemented by an electrostatic assembly process between positively charged hollow SnO₂ nanospheres and negatively charged rGO. Systematic characterizations demonstrate that the as-developed H-SnO₂@rGO has a unique three-dimensional (3D) nanostructure with favorable features for lithium ions storage, which not only provides robust protection against the aggregation and volume changes of the SnO₂ nanospheres, but also ensures high transport kinetics for both electrons and lithium ions. The as-developed H-SnO₂@rGO exhibits an outstanding electrochemical performance as an anode material for lithium-ion batteries, showing a high reversible capacity of 1107 mA h g⁻¹ after 100 cycles at a current density of 0.1 A g⁻¹ and maintaining 552 mA h g⁻¹ over 500 cycles at a current density up to 1 A g⁻¹.