Coherent SnS2/NiS2 hetero-nanosheet arrays with fast charge transfer for enhanced sodium-ion storage

Layered SnS 2 has attracted extensive attention as promising anode material for sodium-ion storage owing to its high theoretical specific capacity. However, the practical performance is always hindered by its inferior rate capability and severe capacity fading. Herein, a novel coherent SnS 2 /NiS 2 hetero-nanosheet arrays on carbon cloth (SnS 2 /NiS 2 @CC) is fabricated through a facile one-step solvothermal method by controlling the synchronous growth of SnS 2 and NiS 2 . Benefiting from the strong coupling effect between SnS 2 and NiS 2 , and thus the markedly elevated electrical conductivity and charge transfer rate for sodiation/desodiation reaction, such composite exhibits significantly enhanced performance than its pure SnS 2 counterpart as the anode for sodium-ion battery, presenting a high reversible capacity (909.2 mA h g −1 of the fifth cycle at 200 mA g −1 ), excellent rate capability (360 mA h g −1 at 5 A g −1 ) and satisfying cycling stability (588.9 and 343.2 mA h g −1 at 0.5 and 2 A g −1 after 100 cycles, respectively). Moreover, the measured Na + diffusion coefficient for such SnS 2 /NiS 2 @CC electrode is almost two orders of magnitude higher than that of pure SnS 2 @CC. Such heterogeneous structuring for enhancing the rate performance could offer an effectively alternative way for the development of advanced electrode materials for energy storage devices.