Cyclically Generated Phase Segregation Synergizing with Si Enhances Lithium-Ion Storage Capability

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Silicon anodes offer high capacity for lithium-ion batteries (LIBs) but suffer from volume expansion and capacity fading.
• Instability of the solid-electrolyte interface exacerbates performance degradation in silicon anodes.

Purpose of the Study:

• To investigate a synergistic effect from Mn-based metal-organic framework (Mn-MOF) phase segregation to modify silicon anodes.
• To enhance the electrochemical performance and cycling stability of silicon anodes in LIBs.

Main Methods:

• A facile self-assembly method was employed to create a Si@Mn-MOF composite.
• Electrochemical performance was evaluated as an anode material in LIBs.
• Cycling stability and capacity retention were assessed over 400 cycles.

Main Results:

• The Si@Mn-MOF composite demonstrated improved reversibility and lithium-ion storage capability.
• A high reversible capacity retention of 1234.4 mAh g^-1 was achieved after 400 cycles.
• The unique composite structure effectively mitigated issues associated with silicon volume expansion.

Conclusions:

• The synergistic effect of Mn-MOF phase segregation offers a promising strategy for stabilizing silicon anodes.
• Si@Mn-MOF composites show potential for commercial application in high-performance LIBs.
• This approach enhances the durability and energy storage capacity of next-generation batteries.