SnO2 Nanoflake Arrays Coated with Polypyrrole on Carbon Cloth as Flexible Anodes for Sodium-Ion Batteries

SnO2 has been extensively studied as an anode material for sodium ion batteries, which, however, has long been subjected to poor conductivity and large volume expansion accompanied with an unsatisfactory electrochemical performance. Here, novel interlaced SnO2 nanoflakes are synthesized directly on a carbon cloth collector via hydrothermal and annealing treatment, and then coated with polypyrrole (PPy) via electrodeposition. The as-prepared flexible SnO2@PPy on carbon cloth exhibits a high initial capacity of 1172.1 mAh g−1 and an outstanding cycling stability with 85% capacity retention after 300 cycles at 0.1 A g−1, which can be contributed to the interlaced SnO2 nanoflakes as well as the coating of PPy. This result shows promising potential for construction of electrode in high-performance energy storage fields.