High-Output, Stretchable, Moisture-Electric Generator Enabled by Tailored Acrylic Acid/Choline Chloride Eutectogel.

Area of Science:

• Materials Science
• Energy Harvesting
• Flexible Electronics

Background:

• Moisture-electric generation (MEG) is a promising technology for sustainable energy in flexible wearable electronics.
• Existing MEG systems suffer from low output voltage, poor current stability, and inadequate material mechanical properties.

Purpose of the Study:

• To develop a high-performance material for moisture-electric generation (MEG) addressing current limitations.
• To investigate the structure-property relationships of a novel poly(acrylic acid)/choline chloride eutectogel (PA-C).

Main Methods:

• Synthesized poly(acrylic acid)/choline chloride (PAA/ChCl) eutectogels (PA-C) using ultraviolet photopolymerization of acrylic acid/ChCl deep eutectic solvent.
• Incorporated N,N -methylenebis(acrylamide) (MBA) as a cross-linking agent to form a triple network structure (covalent, ion pair, hydrogen bonds).
• Systematically studied the effect of the acrylic acid (AA) to choline chloride (ChCl) molar ratio on material properties.

Main Results:

• The PA-C material exhibited a unique triple network structure, providing excellent hydrophilicity and mechanical properties.
• Optimized PA-C demonstrated a tensile strength of 4.92 MPa and elongation at break of 633%.
• The MEG device based on PA-C achieved high ionic conductivity (0.54 S m^-1 at 99% RH), an open-circuit voltage of 1.28 V, and a short-circuit current of 2.20 mA, with a maximum power density of 90 μW cm^-2.

Conclusions:

• The developed PA-C material system significantly enhances MEG device performance, overcoming limitations of existing technologies.
• The flexible and scalable nature of the PA-C based MEG devices enables practical applications for powering low-power electronics.
• This work presents a viable pathway for creating efficient, scalable, and multifunctional power sources for wearable applications.