Molybdenum sulfide selenide ultrathin nanosheets anchored on carbon tubes for rapid-charging sodium/potassium-ion batteries.

The structural stability and reaction kinetics of anodes are essential factors for high-performance battery systems. Herein, the molybdenum sulfide selenide (MoSSe) nanosheets anchored on carbon tubes (MoSSe@CTs) are synthesized by a facile hydrothermal method combining with further selenization/calcination treatment. The unique tubular carbon skeletons expose abundant active sites for the well-dispersed growth of MoS ultrathin nanosheets on both sides of the tubular carbon skeleton. In addition, the further selenization treatment can expand the interlayer spacing of molybdenum sulfide (MoS) nanosheets and facilitate the fast sodium/potassium-ion transition and storage. When used in sodium-ion batteries (SIBs), MoSSe@CTs electrode delivers a specific capacity of 486 mAh g at 1 A g and retains a stable reversible capacity of 465 mAh g after 1000 cycles, indicating its good cycling stability. For potassium-ion batteries (KIBs), the MoSSe@CTs composite shows a capacity of 352 mA hg at 1 A g and a good cycling stability (maintains at 272 mA hg after 1000 cycles). This work shows informative guiding significance for exploring advanced electrode materials of sodium/potassium-ion batteries.