Constructing tin sulfide nanosheets embedded in N-doped graphene frameworks for potassium-ion storage

Potassium-ion batteries (PIBs) have recently emerged as potential energy storage devices, but the development is still limited with lack of stable anode materials. Herein, SnS2 and SnS nanosheets covered by nitrogen-doped graphene (SnS2/NDG and SnS/NDG) nanocomposites are prepared via a simple pyrolysis method, and their potassium-storage properties are evaluated. The as-prepared SnS2/ NDG delivers superior rate capability of 174 mA h g(-1) at 2.0 A g(-1), and a discharge capacity of 221 mA h g(-1) can be obtained at 1.0 A g(-1) after 100 cycles. This is a benefit from the comprehensive encapsulation of NDG, which can effectively alleviate the volume expansion of tin sulfides, as well as enhances the electronic conductivity and fast K+-ion diffusion. This work would provide the experimental guidance for fabricating advanced tin-based hybrid composites for application in PIBs.