Dynamic Dual-network Multifunctional Ionic Gel Based on Phytate Deep Eutectic Solvent for Flexible Sensors

Conductive ionic gels integrating mechanical robustness and dynamic adaptability are highly desirable for flexible electronics, yet their development is hindered by the trade-off between ion-conductive efficiency and structural stability. Herein, a hydrated deep eutectic solvent (DES)-enhanced ionic gel fabricated by integrating phytic acid (PA) and choline chloride (ChCl) into a polyvinyl alcohol (PVA)/polysaccharide sodium alginate (SA) matrix via a cyclic freeze-thaw process is reported. The hydrated DES serves as a dynamic cross-linker and ionic conductor, enabling dual-network interactions through hydrogen bonding and electrostatic forces. The resultant gel achieves a high electrical conductivity of 5.16 S m⁻¹, tunable mechanical strength (0.2–1 MPa), and exceptional strain sensitivity. The ice crystal-like micropores formed during freezing enhance strain dissipation and swelling adaptability. The prepared conductive ionic gels have a wide strain detection range and can detect motion signals from different parts of the human body, and demonstrates excellent freeze resistance at low temperatures (−60°C). PA confers strong antimicrobial activity to the PVA/SA gel, with inhibition circles 6.5 and 4.6 times larger than the sample diameter for E. coli and S. aureus, respectively. This work provides a scalable, eco-friendly strategy to engineer multifunctional ionic gels for next-generation wearable sensors and adaptive interfaces.