Few-layer V₂C/MWCNT with high ionic accessibility for lithium-ion storage

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Vanadium carbide (V2C) MXene exhibits high theoretical capacity for lithium-ion batteries.
• Stacked multilayer V2C structures suffer from poor ionic accessibility and cycling stability.

Purpose of the Study:

• To synthesize few-layer V2C (f-V2C) and integrate it with multi-walled carbon nanotubes (MWCNTs).
• To improve ionic accessibility, specific surface area, and structural stability of V2C for enhanced Li+ storage.

Main Methods:

• Synthesis of few-layer V2C (f-V2C) material.
• Composite formation of f-V2C with multi-walled carbon nanotubes (MWCNTs).
• Electrochemical testing of the f-V2C/MWCNT composite in lithium-ion battery applications.

Main Results:

• The f-V2C/MWCNT composite demonstrates abundant pores, enhancing Li+ ion accessibility.
• MWCNTs improve specific surface area, reduce charge transfer resistance, and increase structural stability.
• Achieved a specific capacity of 531 mA h g-1 at 0.1 A g-1 after 100 cycles, and 166 mA h g-1 at 5.0 A g-1.
• Exhibited excellent cycling stability with 95% capacity retention after 1000 cycles at 5.0 A g-1.

Conclusions:

• The f-V2C/MWCNT composite shows significant potential for high-performance lithium-ion battery applications.
• The enhanced ionic accessibility and structural integrity are key to the superior electrochemical performance.
• This material offers a promising pathway for advanced Li+ storage solutions.