Ambient Stable Triboelectric Nanogenerator Based on Conductive Filler Modified Silicone Rubber with Gas Barrier Encapsulation for Footstep Energy Conversion

Human motion, particularly foot-ground interaction during locomotion, generates substantial biomechanical energy that remains largely underutilized. Triboelectric nanogenerators (TENGs) have emerged as a promising solution for harvesting such energy, yet their long-term performance under ambient humidity remains a major challenge for real-world deployment. Herein, a spring-assisted contact-separation mode TENG is reported, composed of high-temperature vulcanized (HTV) silicone rubber filled with 1 phr of conductive carbon black (600JD). The addition of 600JD increases the surface charge density by 55% compared to unfilled silicone rubber. The optimized device delivers a peak power density of 179.9 mW·m⁻² and is capable of powering over 1,900 commercial LEDs. To overcome moisture sensitivity, a flame-retardant chlorinated isobutylene-isoprene rubber (CIIR) encapsulation layer with excellent gas barrier properties is introduced, enabling stable operation across a broad relative humidity range (30–90% RH). The device retains 98.3% of its initial short-circuit current after more than 1 000 000 mechanical cycles, indicating exceptional durability. Beyond energy harvesting, the TENG also functions as a self-powered sensor capable of footstep detection, step frequency monitoring, and motion pattern recognition. This work presents a resilient and scalable design strategy for ambient-stable TENGs toward footstep energy harvesting and intelligent sensing under variable environmental conditions.