Simply structured wearable triboelectric nanogenerator with milligram-level sensitivity for biomechanical energy harvesting and motion detection

Abstract

Wearable triboelectric nanogenerators (TENGs) often struggle to harmonize fabrication simplicity, stretchability, and high sensitivity. In this study, we present a conductive sponge-based TENG fabricated via a streamlined one-step process, which integrates a porous conductive sponge electrode with textured Ecoflex. The device achieves high pressure sensitivity (3.5 V/N and 0.647 V/N) and detects ultralight forces (14 mg), outperforming conventional designs in resolution. Its inherent flexibility ensures conformal contact during motion, while durability tests confirm stability over 25,000 cycles and resistance to liquids. The CS-SE TENG serves dual roles: as a biomechanical energy harvester, it powers small electronics via hand tapping or walking; as a self-powered sensor, it monitors sitting behavior (posture, duration) and tracks motion metrics (steps, speed, calories) through MATLAB-processed signals. Insole integration demonstrates real-time gait analysis, while chair-mounted deployment addresses sedentary health risks. By combining single-step fabrication, milligram-level sensitivity, and energy-sensing duality, this work offers a scalable platform for wearable technologies, bridging sustainable energy harvesting with precision health monitoring.