Interface Engineering of Styrenic Polymer Grafted Porous Micro-Silicon/Polyaniline Composite for Enhanced Lithium...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Silicon (Si) anodes offer high capacity for next-generation Li-ion batteries (LIBs).
• Si anodes suffer from performance degradation due to volume expansion and low conductivity.
• Improving interfacial properties and conductivity is crucial for stable Si anodes.

Purpose of the Study:

• To develop a facile method for creating stable and conductive Si anodes for LIBs.
• To investigate the effect of a polymer coating on the electrochemical performance of Si anodes.
• To enhance the cycle stability and capacity retention of Si-based anodes.

Main Methods:

• A one-pot pyrolysis method using polystyrene sulfonate (PSS) at low temperatures (≤400 °C).
• Metal-assisted chemical etching to create porous micron silicon (por-mSi).
• Formation of a Si-C/Si-O-C covalent bond between PSS-derived layer and Si surface.
• Coating PSS-grafted por-mSi with polyaniline (PANI) for enhanced conductivity.

Main Results:

• A thin carbonaceous layer formed on the Si surface via PSS thermolysis improved interfacial properties.
• The PSS-grafted por-mSi@PSS/PANI anode exhibited a high reversible capacity of ~1500 mAh g⁻¹ at 0.1 A g⁻¹ after 100 cycles.
• The double-layer coating (phenyl moieties and PANI) enhanced anode stability and facilitated Li⁺ ion transport.

Conclusions:

• Polymer-modified silicon anodes, particularly por-mSi@PSS/PANI, demonstrate significant promise for advanced LIB applications.
• The developed method offers an effective strategy to overcome the limitations of Si anodes.
• This approach contributes to the development of high-performance energy storage solutions.