Cobalt-Doping SnS2 Nanosheet towards High-Performance Anode for Sodium Ion Batteries
Layered SnS2 are considered as a promising anode candidate for sodium-ion batteries yet suffering from low initial Coulombic Efficiency, limited specific capacity and rate capability. Herein, we report a cobalt metal cation doping strategy to enhance the electrochemical performance of SnS2 nanosheet array anode through a facile hydrothermal method. Benefitting from this special structure and heteroatom-doping effect, this anode material displays a high initial Coulombic Efficiency of 57.4%, superior discharge specific capacity as high as 1288 mAh g-1 at 0.2 A g-1 after 100 cycles and outstanding long-term cycling stability with a reversible capacity of 800.4 mAh g-1 even at 2 A g-1. These excellent performances could be ascribed to the Co-doping effect that can increase the interlayer spacing and produce rich defects, regulate the electronic environment and improve conductivity. Besides, carbon cloth substrate can maintain the integrity of electrode material framework and buffer their volume variation, thus boosting intrinsic dynamic property and enhancing sodium storage performance.