Liquid-Phase Exfoliated Ws2-Graphene Composite Anodes For Potassium-Ion Batteries

Tungsten disulfide (WS2) has been recognized as a promising anode material for rechargeable potassium-ion batteries (PIBs). However, its K-ion intercalation capacity is limited to similar to 60 mAh.g(-1). Here, we report a WS2-graphene composite anode which is fabricated through simple filtration of liquid-phase exfoliated WS2 and graphene nanosheet delivers a significantly improved specific capacity of 137 mAh.g(-1) at a current density of 10 mA.g(-1). The composite anodes also exhibit remarkable rate capability and long-term cyclability over 500 cycles. These results highlight the WS2-graphene composite structure as a promising anode material for long lifespan rechargeable potassium-ion batteries.