Tin Oxide/Graphene Aerogel Nanocomposites Building Superior Rate Capability for Lithium Ion Batteries

Highlights: • The SnO₂/GA nanocomposites were successfully synthesized via a hydrothermal method. • The performance of nanocomposite anodes highly depended on the hydrothermal time. • The 3-4 nm-sized SnO₂/GAs showed enhanced cycling performance and rate performance. - Abstract: SnO₂ has attracted intense interest for use as an anode material for lithium ion batteries because of various advantages of the high theoretical capacity and low-cost. Unfortunately, SnO₂ anode material suffers from the huge volume change and poor electrical conductivity. In order to address these problems, in this work, SnO₂/graphene aerogel composites have been successfully synthesized by a facile hydrothermal approach. 3-4 nm-sized SnO₂ nanoparticles are uniformly dispersed over graphene aerogels. Our results indicate that the hydrothermal reaction time highly affects the electrode performance of the anodes. The nanocomposite electrode with reaction time of 3 h shows increased electrochemical performance with high energy capacity, long cycle life, and superior rate capability. After 100 cycles, it can deliver a high discharge capacity of 662 mAh g⁻¹ at 100 mA g⁻¹. At 500 mA g⁻¹, it can still yield a discharge capacity of 619.7 mAh g⁻¹ after 723 cycles. The performance improvement can attribute to the graphene aerogel, which can suppress the aggregation of SnO₂ nanoparticles, enhance the conductivity of SnO₂, and increase their structural stability during cycling. This study strongly demonstrates that the SnO₂/graphene aerogel composite is a promising anode material building high performance lithium ion batteries