Manipulating Oxidation of Silicon with Fresh Surface Enabling Stable Battery Anode

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Silicon (Si) is a promising anode material for next-generation lithium-ion batteries (LIBs) due to its high theoretical capacity.
• However, Si anodes suffer from large volume expansion and poor cycling stability.

Purpose of the Study:

• To fabricate a stable silicon oxide-carbon (SiO/C) nanocomposite for enhanced LIB anode performance.
• To investigate the effect of controllable oxidation and carbon coating on Si anode stability and electrochemical properties.

Main Methods:

• Fabrication of SiO/C nanocomposite via mild hydrothermal reaction between Si particles and H₂O.
• Synchronous conducting carbon coating.
• Electrochemical characterization of the SiO/C composite as an anode material in LIBs.

Main Results:

• Controllable oxidation of Si particles to uniform SiO was achieved after removing the native passivation layer.
• The SiO/C composite exhibited excellent stability at both particle and electrode levels during electrochemical cycling.
• The as-fabricated SiO/C composite delivered a high reversible capacity of 1133 mAh g^-1 at 0.5 A g^-1 with 89.1% retention after 200 cycles.
• A graphite-SiO/C hybrid electrode showed a reversible capacity of 496 mAh g^-1 with 90.1% retention after 100 cycles.

Conclusions:

• The developed SiO/C nanocomposite is a highly stable and high-capacity anode material for LIBs.
• Controllable oxidation and simultaneous carbon coating are effective strategies to improve Si anode performance.
• This material holds potential for next-generation energy storage applications.