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

Abstract

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 MoS 2 -ZnS (MoS 2 -ZnS@C) heterostructures were constructed by treating the MOF precursor with a onestep sulfurization/carbonization strategy. The MoS 2 -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 MoS 2 -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 MoS 2 -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 MoS 2 -ZnS@C/ether-based electrolyte/Na 3 V 2 (PO 4 ) 3 . The construction of heterostructures for improving the electrochemical performance can also be applicable to other battery material fields.

Structure and Defect Engineering of V3S4−xSex Quantum Dots Confined in a Nitrogen‐Doped Carbon Framework for High‐Performance Sodium‐Ion Storage

“…The high specific surface area and hierarchical porous structure could facilitate electrolyte immersion and fast ion diffusion. [49,50] The thermo-gravimetric analyses (TGA) were implemented to determine the content of carbon (Figure S8, Supporting Information). Based on the final residual weight of the V 2 O 5 , it can be calculated that the mass fraction of V 3 S 4−x Se x and NC in V 3 S 4−x Se x /NC is about 38.7% and 61.3%, respectively.…”