Mo_4.8Si₃C_0.6/MoC/SiOC Nanocomposite: A kinetics-Enhanced Anode Material for Lithium-Ion Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Silicon oxycarbide (SiOC) is a potential anode material for lithium-ion batteries.
• Current limitations include low initial Coulombic efficiency (ICE), slow ion kinetics, and poor electrical conductivity.

Purpose of the Study:

• To develop SiOC-based ceramic nanocomposites for enhanced lithium-ion storage.
• To investigate the role of molybdenum incorporation on electrochemical performance.

Main Methods:

• Preparation of SiOC-based ceramic nanocomposites from molybdenum-containing polysiloxane precursors.
• In situ formation of Nowotny phase (Mo4.8Si3C0.6) and MoC nanocrystals within the SiOC matrix.
• Electrochemical characterization of the nanocomposites for lithium-ion storage.

Main Results:

• The Mo4.8Si3C0.6/MoC/SiOC nanocomposites achieved a reversible capacity of 883.59 mAh g-1.
• Initial Coulombic efficiency (ICE) increased from 67.7% to 75.9%.
• A specific capacity of 455.2 mAh g-1 was retained after 500 cycles at 1 A g-1.

Conclusions:

• The enhanced performance is attributed to the synergistic effect of Mo4.8Si3C0.6 and MoC nanocrystals.
• The unique microstructure optimizes electrode kinetics, providing high capacity, reversibility, and stability.
• These nanocomposites represent a promising advancement for high-performance lithium-ion batteries.