Ultrathin SnO2 nanosheets anchored on graphene with improved electrochemical kinetics for reversible lithium and sodium storage

SnO2 is regarded to be promising for both Li-ion and Na-ion batteries. Thus, it is imperative to fabricate SnO2-based anode with improved lithiation reaction kinetics using simple but effective method. Herein, we develop a one-pot hydrothermal route to fabricate two-dimensional SnO2 nanosheets and the graphene supported SnO2 nanosheet composite with decreased SnO2 nanosheet of about 5-10 nm. The ultrathin nanosheet structure anchored on graphene supporting can effectively accelerate the conversion/alloying reaction. Electrochemical researches demonstrate that the reaction kinetics of the lithiation/delithiation reaction can be significantly enhanced by the graphene supported SnO2 nanosheets. As a result, a capacity of 817.2 mAh g(-1) after 100 cycles in the potential window of 0.01 to 3 V are achieved at 500 mA g(-1). The full cell performance and the sodium storage performance are both demonstrated to be good. These promising results suggest that such strategy to fabricate two-dimensional SnO2-based anode is of great interest for next-generation Li-ion and Na-ion batteries.