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.

Keywords: Fe2O3 nanoparticles; Li+/Na+ storage; electrochemistry; graphite C; interlayer-expanded MoS2.