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.