WS₂ Nanotube-Embedded SiOC Fibermat Electrodes for Sodium-Ion Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Layered transition metal dichalcogenides (TMDs), like tungsten disulfide (WS2), show potential for batteries and supercapacitors.
• TMD-based electrodes face challenges including capacity fading, voltage hysteresis, and polysulfide dissolution.

Purpose of the Study:

• To enhance the electrochemical performance of WS2-based electrodes by fabricating composite fibers.
• To mitigate capacity fading and other adverse phenomena in WS2 nanotubes (WS2NTs) for energy storage.

Main Methods:

• Electrospinning of WS2 nanotubes (WS2NTs) within a preceramic polymer solution.
• Pyrolysis of the electrospun fibers to form WS2NTs embedded in a silicon-oxycarbide (SiOC) ceramic matrix.
• Electrochemical testing of the composite fibers as electrodes.

Main Results:

• The WS2NT/SiOC composite electrode demonstrated a high initial capacity of 454 mAh g-1.
• The composite electrode exhibited 2-3 times higher capacity retention compared to neat WS2NT electrodes.
• Synergistic effects between WS2NT and the SiOC matrix curbed capacity fading.

Conclusions:

• WS2NTs embedded in a SiOC matrix offer superior electrochemical performance for energy storage.
• The composite fiber structure effectively addresses the limitations of traditional TMD-based electrodes.
• This approach presents a promising strategy for developing advanced electrode materials.