Construction of MoS2-ZnS@C Heterostructures by Multiple Organic Framework Combination for Fast and Stable Sodium/Potassium Storage

The establishment of three-dimensional structures, carbon coating, and proper defects is an effective strategy to improve electrochemical performance of molybdenum sulfide. In this work, carbon-coated MoS2-ZnS (MoS2-ZnS@C) heterostructures were constructed by treating the MOF precursor with a one-step sulfurization/carbonization strategy. The MoS2-ZnS@C heterostructures not only introduce abundant C–S–C and C–N bonds which contribute to ion storage with enhancive active sites but also effectively accelerate ion diffusion and reaction kinetics. The corresponding reaction mechanism was revealed via XRD and HR-TEM tests. The anode of MoS2-ZnS@C heterostructures shows outstanding rate capability (309 mAh g–1 at 10 A g–1) and long cycle stability (343 mAh g–1 after 1200 cycles at 5 A g–1) in sodium-ion batteries (SIBs). Meantime, the MoS2-ZnS@C heterostructure anode also exhibits enhanced potassium storage performances, delivering a superior rate capability (80 mAh g–1 at 5 A g–1) and superior long cycle performance (297 mAh g–1 after 100 cycles at 0.5 A g–1). In addition, a high specific capacity of 270 mAh g–1 is achieved at 1 A g–1 in a full cell made up of MoS2-ZnS@C/ether-based electrolyte/Na3V2(PO4)3. The construction of heterostructures for improving the electrochemical performance can also be applicable to other battery material fields.