Two-Dimensional SnSe2 /CNTs Hybrid Nanostructures as Anode Materials for High-Performance Lithium-Ion Batteries

Abstract

Tin diselenide (SnSe₂ ), as an anode material, has outstanding potential for use in advanced lithium-ion batteries. However, like other tin-based anodes, SnSe₂ suffers from poor cycle life and low rate capability due to large volume expansion during the repeated Li⁺ insertion/de-insertion process. This work reports an effective and easy strategy to combine SnSe₂ and carbon nanotubes (CNTs) to form a SnSe₂ /CNTs hybrid nanostructure. The synthesized SnSe₂ has a regular hexagonal shape with a typical 2D nanostructure and the carbon nanotubes combine well with the SnSe₂ nanosheets. The hybrid nanostructure can significantly reduce the serious damage to electrodes that occurs during electrochemical cycling processes. Remarkably, the SnSe₂ /CNTs electrode exhibits a high reversible specific capacity of 457.6 mA h g^-1 at 0.1 C and 210.3 mA h g^-1 after 100 cycles. At a cycling rate of 0.5 C, the SnSe₂ /CNTs electrode can still achieve a high value of 176.5 mA h g^-1 , whereas a value of 45.8 mA h g^-1 is achieved for the pure SnSe₂ electrode. The enhanced electrochemical performance of the SnSe₂ /CNTs electrode demonstrates its great potential for use in lithium-ion batteries. Thus, this work reports a facile approach to the synthesis of SnSe₂ /CNTs as a promising anode material for lithium-ion batteries.

Keywords: anode materials; electrochemistry; lithium ion batteries; nanotubes; tin.