Recyclable Polysaccharide-Based Supramolecular Ionogel Electrolytes for Flexible Supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Increasing environmental concerns regarding fossil fuels necessitate the development of sustainable materials for energy storage.
• Advanced electrochemical energy storage (EES) devices require efficient and eco-friendly electrolytes.

Purpose of the Study:

• To develop a green and recyclable supramolecular ionogel polymer electrolyte for advanced EES devices.
• To investigate the performance of a glycol chitosan and ionic liquid-based ionogel in supercapacitors.

Main Methods:

• Fabrication of a supramolecular ionogel electrolyte using glycol chitosan (GC) and imidazolium-based ionic liquids (IL).
• Characterization of the ionogel's ionic conductivity, voltage window, and electrochemical performance in a supercapacitor.
• Evaluation of the supercapacitor's capacitance, energy density, power density, and cycling stability.
• Assessment of the ionogel's recyclability and environmental impact.

Main Results:

• The optimized GC$_{0.1}$-DMSO$_{1}$/IL$_{1}$ ionogel electrolyte achieved an ionic conductivity of 4.4 mS cm$^{-1}$ at 25 °C.
• The supercapacitor demonstrated a stable voltage window of 2.5 V, a specific capacitance of 40.0 F g$^{-1}$ at 1 A g$^{-1}$, and a maximum energy density of 22.2 Wh kg$^{-1}$.
• Excellent capacitance retention of 94.7% was achieved after over 700 charge-discharge cycles.
• The ionogel was easily recycled in water without environmental hazards.

Conclusions:

• The developed polysaccharide-based supramolecular ionogel electrolyte shows significant potential for flexible and sustainable EES applications.
• This study highlights a promising strategy for creating environmentally friendly and high-performance energy storage materials.