A plant-stabilized and self-initiated liquid metal hydrogel for high-performance multifunctional sensing and infrared camouflage

Abstract

Achieving a stable dispersion of liquid metal within hydrogels remains a key challenge for developing durable multifunctional sensors. Here, we report a green and facile one-pot synthesis of high-performance eutectic gallium–indium (EGaIn)-reinforced hydrogels via a dual-level stabilization and interfacial reinforcement strategy. This strategy employs the synergistic effect of plant-derived tannic acid (TA) and guar gum (GG) to homogeneously disperse EGaIn droplets, followed by their spontaneous polymerization and cross-linking without any external initiators. The resulting hydrogel integrates remarkable stretchability (1770%), high toughness (3.75 MJ m⁻³), strong adhesion to diverse substrates, and exceptional anti-swelling capacity (swelling ratio of 4.1%). It also maintains high electrical conductivity (11.2 mS cm⁻¹), enabling real-time and accurate monitoring of human motions. Furthermore, the hydrogel exhibits efficient photothermal conversion, demonstrating great potential for infrared camouflage applications. This work provides a universal and sustainable platform for fabricating integrated soft materials for next-generation wearable electronics and adaptive interfaces.