Boosting Ionic Conductivity by Ordering Nanoparticles within All-Polymer Poly(ethylene oxide) (PEO) Nanocomposites

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemistry

Background:

• Semicrystalline poly-(ethylene oxide) (PEO) is a promising polymer matrix for solid-state electrolytes.
• Achieving high ionic conductivity in polymer electrolytes is crucial for advanced battery technologies.
• Nanoparticle incorporation can modify polymer properties, but controlled ordering is challenging.

Purpose of the Study:

• To investigate the effect of ordered ion-conducting nanoparticles on the ionic conductivity of PEO.
• To establish a method for aligning nanoparticles within a PEO matrix.
• To enhance the performance of nanocomposite polymer electrolytes.

Main Methods:

• Synthesized lithium sulfonamide functional polymeric methacrylic nanoparticles (NPs).
• Controlled PEO crystallization kinetics between 52-56 °C to achieve NP ordering.
• Utilized polarized light optical microscopy (PLOM), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS) for characterization.

Main Results:

• Demonstrated successful alignment of nanoparticles within the PEO interlamellar regions.
• Observed an 8-fold increase in ionic conductivity at room temperature due to NP alignment.
• Achieved a conductivity of 4.6 × 10^-5 S cm^-1 at 80 °C with lithium single-ion conducting behavior.

Conclusions:

• The ordering of ion-conducting nanoparticles within PEO significantly enhances ionic conductivity.
• Controlled crystallization is an effective strategy for achieving nanoparticle alignment in polymer matrices.
• This approach offers a pathway to develop high-performance nanocomposite polymer electrolytes for electrochemical applications.