Preparation of novel SnO ₂-B ₂O ₃ core-shell nanocomposite and their lithium storage ability

Herein we reported a novel SnO ₂-B ₂O ₃ core-shell nanocomposite synthesized with a modified molten-salt decomposition method, in which SnO ₂ particles were firstly dispersed in the molten SnSO ₄-B ₂O ₃ system, followed by solidification of a hard B ₂O ₃ shell. By limiting the volume expansion of SnO ₂ particles with the super-hard B ₂O ₃ layer, the electrochemical performances of the SnO ₂-B ₂O ₃ electrode were enhanced significantly, in terms of both the initial discharge capacity and capacity retention. The 100th cycle reversible capacity of the SnO ₂-B ₂O ₃ electrode remained as high as 537 mA h g ^-1 at a current density of 156 mA g ^-1. This method is greatly promising for a large-scale synthesis of nanosized SnO ₂ anode materials.