α-Fe_2O_3 Nanoparticles Decorated C@MoS_2 Nanosheet Arrays with Expanded Spacing of (002) Plane for Ultrafast and High Li/Na-Ion Storage

摘要

MoS_2 nanosheets as a promising 2D nanomaterial have extensive applications in energy storage and conversion, but their electrochemical performance is still unsatisfactory as an anode for efficient Li~+/Na~+ storage. In this work, the design and synthesis of vertically grown MoS_2 nanosheet arrays, decorated with graphite carbon and Fe_2O_3 nanoparticles, on flexible carbon fiber cloth (denoted as Fe_2O_3@C@MoS_2/CFC) is reported. When evaluated as an anode for lithium-ion batteries, the Fe_2O_3@C@MoS_2/CFC electrode manifests an outstanding electrochemical performance with a high discharge capacity of 1541.2 mAh g~(-1) at 0.1 A g~(-1) and a good capacity retention of 80.1% at 1.0 A g~(-1) after 500 cycles. As for sodium-ion batteries, it retains a high reversible capacity of 889.4 mAh g~(-1) at 0.5 A g~(-1) over 200 cycles. The superior electrochemical performance mainly results from the unique 3D ordered Fe_2O_3@C@MoS_2 array-type nanostructures and the synergistic effect between the C@MoS_2 nanosheet arrays and Fe_2O_3 nanoparticles. The Fe_2O_3 nanoparticles act as spacers to steady the structure, and the graphite carbon could be incorporated into MoS_2 nanosheets to improve the conductivity of the whole electrode and strengthen the integration of MoS_2 nanosheets and CFC by the adhesive role, together ensuring high conductivity and mechanical stability.