Nitrogen Plasma-Treated Core-Bishell Si@SiO@TiO_2-δ: Nanoparticles with Significantly Improved Lithium Storage...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Silicon (Si) anodes offer high capacity for lithium-ion batteries (LIBs).
• Volume expansion during cycling causes poor stability, hindering commercial use.
• Developing stable Si anodes is crucial for advanced energy storage.

Purpose of the Study:

• To design a novel Si-based anode with enhanced cycling stability and rate performance.
• To address the volume expansion challenge in Si anodes for LIBs.
• To improve the electrochemical performance of Si anodes through a core-bishell nanostructure.

Main Methods:

• Fabrication of a nitrogen plasma-treated core-bishell nanostructure with Si nanoparticles encapsulated in SiO and N-doped TiO2-δ shells.
• Utilizing SiO and TiO2 as binary buffer matrices to accommodate volume changes.
• Employing N-doped TiO2-δ shell to improve electrical conductivity and stabilize solid electrolyte interphase (SEI) films.

Main Results:

• The core-bishell nanostructure effectively buffers Si volume expansion during cycling.
• The N-doped TiO2-δ shell enhances electrical conductivity and SEI stability.
• The Si anodes demonstrated superior cycling stability, retaining 650 mA h g⁻¹ at 200 mA g⁻¹ after 300 cycles.
• Significantly improved rate performance was observed.

Conclusions:

• The synergistic effect of SiO and N-doped TiO2-δ bishells significantly enhances the electrochemical performance of Si anodes.
• This nanostructure design offers a promising strategy for developing practical Si-based anodes for LIBs.
• The developed material shows potential for next-generation high-performance lithium-ion batteries.