Multiscale-Engineered Porous Triboelectric Nanogenerator for Durable Energy Harvesting and Self-Powered Motion Recognition

Wearable triboelectric nanogenerators require not only high electrical output but also mechanical compliance, elastic recovery, and long-term operational stability. Here, we report a multiscale-engineered porous triboelectric nanogenerator based on sugar-templated PDMS integrated with ZnO nanorods and MWCNTs. The optimized porous composite exhibited a low effective modulus of 32.5 kPa, 99% resilience at 20% strain, and stable output under repeated contact-separation operation. Under optimized conditions, the device generated 250 V, 2 μA, and a peak power density of 91.2 mW m-2. The performance enhancement arises from porous-structure-induced contact improvement, ZnO-assisted dielectric polarization and charge-retention-related behavior, and MWCNT-assisted charge transport. The harvested energy charged commercial capacitors, powered small electronics, and illuminated a 324-LED array. Integrated into an in-shoe platform, the device enabled subject-independent gait recognition with a mean leave-one-subject-out accuracy of 97.9%.