Room-Temperature Self-Standing Cellulose-Based Hydrogel Electrolytes for Electrochemical Devices

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Growing demand for sustainable materials drives biopolymer research.
• Hydrogels are promising electrolytes for flexible electrochemical devices due to their ionic conductivity and mechanical properties.

Purpose of the Study:

• To develop and characterize cellulose-based hydrogels as aqueous electrolytes for electrochemical applications.
• To explore the potential of these hydrogels in electrochromic devices and printed batteries.

Main Methods:

• Synthesis of semi-interpenetrating network (semi-IPN) hydrogels using hydroxyethyl cellulose (HEC) and divinyl sulfone (DVS) with carboxymethyl cellulose (CMC).
• Confirmation of reaction using Nuclear Magnetic Resonance (NMR) and Fourier-Transform Infrared Spectroscopy (FTIR).
• Rheological characterization using small-amplitude oscillatory shear (SAOS) and ionic conductivity measurements.

Main Results:

• Tunable rheological properties achieved by varying gel composition.
• High ionic conductivity observed in the range of mS cm^-1.
• Successful fabrication of an electrochromic device (ECD) with enhanced performance and a printed Zinc/MnO₂ battery with improved functionality.

Conclusions:

• Cellulose-based hydrogels are effective aqueous electrolytes for electrochemical devices.
• The tunable nature and high conductivity of these hydrogels support their use in sustainable flexible electronics.
• This research highlights a pathway towards more environmentally friendly electrochemical energy storage and display technologies.