摘要
To overcome the issues of fast capacity fading and poor rate capacity for tin dioxide (SnO 2 ) anode materials , an effective strategy is explored to fabricate nanostructured SnO 2 @carbon composites (SnO 2 @C) with large specific surface area, abundant cavity and confined dimension, considering the peculiar nanostructure to achieve increased contact interface between the active materials and the electrolyte, restricted agglomeration of SnO 2 , buffered volume variation, enhanced structure stability, shortened diffusion distance of lithium-ion and electron and improved electronic conductivity . Herein, two kinds of hollow SnO 2 @C nanostructures, namely hollow SnO 2 @C spheres and SnO 2 @C tubes are prepared by a simple approach. Comparing with general strategies involved templates, the preparation process in our strategy is greatly simplified, and the typical and tedious respective SnO 2 coating, polysaccharides coating and template removal are avoided, instead, the three processes are achieved simultaneously. It is believed that our strategy may pave the way for facile preparation of various microstructures of hollow SnO 2 @C composites with relatively uniform size and to a wide variety of applications. More importantly, when tested as promising anode materials for lithium-ion batteries, both the two hollow SnO 2 @C nanostructures exhibited superior electrochemical performance due to the synergistic effect of hollow nanostructure and relatively uniform carbon coating. The SnO 2 @C tubes delivered a reversible capacity of 587.1 mAh g −1 at 200 mA g −1 after 100 cycles. More importantly, the hollow SnO 2 @C spheres delivered a reversible capacity of 612.9 mAh g −1 at 200 mA g −1 even after 300 cycles.
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