Synthesis and characterization of CNT@SnO2 decorated graphene anodes for Li-ion batteries as free-standing and flexible

SnO2 anode material is considered to be a promising anode material for lithium-ion batteries owing to its high theoretical capacity. However, the application of SnO2 has been dramatically restricted because of pulverization led by the volume expansion during the charge/discharge process. To overcome these drawbacks, herein, SnO2 coated carbon nano tubes (CNT@SnO2) decorated graphene anode as free-standing and flexible was prepared and investigated for Li-ion anode application. The fine dispersion of SnO2 nanocrystals onto CNT surfaces and decoration of this structure between graphene layers not only suppresses the volume expansion but also effectively avoids aggregation of the SnO2, increases the specific surface area and active sites, and improves the electrical conductivity. The free-standing and flexible composite anode exhibit excellent reversible capacity, high Coulombic efficiency, and good capacity retention. [GRAPHICS] .

Automated summary

In this study, a free-standing and flexible carbon nanotube@tin dioxide (CNT@SnO2) decorated graphene anode was prepared, which solved the pulverization issue caused by the volume expansion of tin dioxide. This structure not only effectively suppresses volume expansion, but also increases the specific surface area and active sites, and improves electrical conductivity, exhibiting excellent reversible capacity, high Coulombic efficiency and capacity retention.