α-Fe2 O3 Nanoparticles Decorated C@MoS2 Nanosheet Arrays with Expanded Spacing of (002) Plane for Ultrafast and High Li/Na-Ion Storage.

Abstract

MoS2 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 MoS2 nanosheet arrays, decorated with graphite carbon and Fe2 O3 nanoparticles, on flexible carbon fiber cloth (denoted as Fe2 O3 @C@MoS2 /CFC) is reported. When evaluated as an anode for lithium-ion batteries, the Fe2 O3 @C@MoS2 /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 Fe2 O3 @C@MoS2 array-type nanostructures and the synergistic effect between the C@MoS2 nanosheet arrays and Fe2 O3 nanoparticles. The Fe2 O3 nanoparticles act as spacers to steady the structure, and the graphite carbon could be incorporated into MoS2 nanosheets to improve the conductivity of the whole electrode and strengthen the integration of MoS2 nanosheets and CFC by the adhesive role, together ensuring high conductivity and mechanical stability.