Triple-Shell Hollow FeS/MoS₂ Heterostructure Anodes: Synergistic Effects of Built-In Electric Field on Ultra-Stable...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal sulfides are promising anode materials for sodium-ion batteries (SIBs) due to high capacity and low cost.
• Challenges include slow ion kinetics and low conductivity in traditional sulfide structures.
• Designing efficient heterostructures is crucial for improving SIB performance.

Purpose of the Study:

• To engineer a novel hollow triple-shell FeS/MoS2@NC structure for SIB anodes.
• To enhance sodium ion (Na+) storage kinetics and overall battery performance.
• To investigate the electrochemical properties and stability of the new material.

Main Methods:

• Fabrication of a hollow triple-shell FeS/MoS2@NC structure via simultaneous sulfidation of Fe2(MoO4)3.
• Integration of molecular and microstructural engineering for enhanced conductivity.
• Electrochemical characterization including cycling performance and rate capability tests.

Main Results:

• The FeS/MoS2@NC structure exhibited a high reversible capacity of 611.8 mAh g-1 at 0.1 A g-1.
• Exceptional cycling stability was demonstrated, retaining 451.5 mAh g-1 after 9000 cycles at 5 A g-1.
• A full cell using this anode showed remarkable performance, delivering 322.2 mAh g-1 after 400 cycles at 1 A g-1.

Conclusions:

• The hollow triple-shell FeS/MoS2@NC structure effectively addresses kinetic limitations and volume expansion in SIB anodes.
• The unique structure and synergistic effects between FeS and MoS2 significantly boost electrochemical performance.
• This work offers new insights for developing high-performance metal sulfide heterostructures for next-generation SIBs.