A Transparent Hydrogel-Ionic Conductor with High Water Retention and Self-Healing Ability

• Published in: Materials Vol. 17; no. 2; p. 288
• Main Authors: Lee, Yangwoo, So, Ju-Hee, Koo, Hyung-Jun
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.01.2024
• Subjects: Adenosine triphosphate; agarose; Cellulose; Dehydration; hydrogel; Hydrogels; Ion currents; ionic gel; Mechanical properties; Nanoparticles; Polymers; Polyvinyl alcohol; Pressure sensors; Retention; sensor; Sensors; Sodium; Sodium chloride; Spectrum analysis; Sucrose; Water loss; United States > US; ionic gel; sensor; hydrogel; agarose
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17020288

This study presents a transparent and ion-conductive hydrogel with suppressed water loss. The hydrogel comprises agarose polymer doped with sucrose and sodium chloride salt (NaCl-Suc/A hydrogel). Sucrose increases the water retention of the agarose gel, and the Na and Cl ions dissolved in the gel provide ionic conductivity. The NaCl-Suc/A gel shows high retention capability and maintains a 45% water uptake after 4 h of drying at 60 °C without encapsulation at the optimum gel composition. The doped NaCl-Suc/A hydrogel demonstrates improved mechanical properties and ionic conductivity of 1.6 × 10 (S/cm) compared to the pristine agarose hydrogel. The self-healing property of the gel restores the electrical continuity when reassembled after cutting. Finally, to demonstrate a potential application of the ion-conductive hydrogel, a transparent and flexible pressure sensor is fabricated using the NaCl-Suc/A hydrogel, and its performance is demonstrated. The results of this study could contribute to solving problems with hydrogel-based devices such as rapid dehydration and poor mechanical properties.