Dynamic Bond-Constructed Hydrogel-Triboelectric Systems with Self-Healing, Strain Sensing, and Energy Harvesting Capabilities

Hydrogels have emerged as promising materials for intelligent sensing and energy storage applications, but their practical applications are often hindered by their limited durability and signal instability upon mechanical damage. Addressing this challenge, we developed a rapidly self-healing hydrogel (P(AM-DAAM-AMPS)/PEI-AGO/ADH) through a synergic strategy of dynamic hydrazone bonds, Schiff base interactions, and electrostatic interactions. The hydrogel demonstrated excellent self-healing capability (98.37% efficiency within 4 h), overcoming the conventional acrylamide-based systems. As a strain sensor, the material exhibited high sensitivity (gauge factor = 3.8 at 150% strain), enabling precise monitoring of subtle physiological activities, including facial expressions and throat movements. When assembled into a triboelectric nanogenerator (TENG), the system generated an electrical output (55.2 V, 8.3 μA), functioning dually as an energy harvester and self-powered motion sensor. Remarkably, the self-healing property enabled the hydrogel to preserve the sensing performance after damage–repair cycles, significantly extending the device lifetime. These findings demonstrate the great potential of the fabricated hydrogels in the fields of next-generation wearable health monitors and human–machine interfaces.