Highly Durable and Easily Integrable Triboelectric Foam for Active Sensing and Energy Harvesting Applications

Triboelectric nanogenerators (TENGs) have potential applications as active sensors or energy harvesters in self-powered sensors and systems as they enable harvesting and conversion of mechanical energy into electrical energy. TENG development allows high-efficiency energy harvesting capability and outstanding sensing characteristics, such as excellent output performance, high durability, reliable stability, easy integration, and convenient fabrication, among others. A triboelectric foam (T-Foam) composed of a foam material with an embedded soft electrode is proposed in this study. The T-Foam inherits the dominant mechanical properties of the foam material, which allows it to be freely folded, compressed, and kneaded, as well as immediate recovery upon stimulus withdrawal. The durability and stability of the T-Foam are tested for a 0.1842 g sample; after stamping 14 times with a 158.6 lb tester, its output performance remained nearly identical. These properties indicate that the T-Foam can be easily integrated into products, such as insoles, schoolbags, and seat mats, to build smart applications for motion, health, and safety monitoring. When driven by a polytetrafluoroethylene plate, a T-Foam sample of 135 × 135 × 25 mm³ exhibits considerable energy harvesting capability, with the output power as high as 5.46 mW.