Quaternized Polysulfone as a Solid Polymer Electrolyte Membrane with High Ionic Conductivity for All-Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Solid polymer electrolytes (SPEs) are promising alternatives to liquid electrolytes in zinc-air batteries (ZABs) due to improved safety and stability.
• Developing high-performance SPEs is crucial for advancing all-solid-state ZAB technology.

Purpose of the Study:

• To synthesize and characterize novel anion-exchange solid polymer electrolytes (A-SPEs) for ZAB applications.
• To investigate the effect of functionalization degree on A-SPE properties and ZAB performance.
• To evaluate the stability and rechargeability of ZABs utilizing the developed A-SPEs.

Main Methods:

• Anion-exchange solid polymer electrolytes (A-SPEs) synthesized via electrophilic aromatic substitution and substitution reactions.
• Thin films prepared using the solvent casting method.
• Characterization using ¹H-NMR, FT-IR, TGA, ion-exchange capacity (IEC), and KOH uptake measurements.
• Electrochemical performance evaluation including ionic conductivity, power density, and rechargeability tests in ZABs.

Main Results:

• A-SPEs with varying functionalization (PSf30/PSf120) were successfully synthesized and characterized.
• Higher functionalization (PSf120) led to increased IEC and hydroxide conductivity (22.19 mS cm⁻¹).
• PSf120-based ZABs exhibited superior power density (70 vs. 50 mW cm⁻²) and enhanced rechargeability compared to benchmarks.
• Postmortem analysis showed reduced ZnO formation for PSf120, indicating improved zinc electrode stability.

Conclusions:

• The developed A-SPEs, particularly PSf120, demonstrate significant potential for improving all-solid-state ZAB performance.
• Increased functionalization enhances ionic conductivity and battery stability by mitigating zinc electrode passivation.
• These findings pave the way for more efficient and durable solid-state zinc-air batteries.