Bio-based polyurethane triboelectric nanogenerator with superior low-temperature self-healing performance for unmanned surveillance

Damaged flexible triboelectric nanogenerators face difficulties in autonomous healing at low temperatures, limiting their application range. Impeded dynamic network reconstruction presents a challenge in developing materials for autonomous low-temperature healing. This study constructed a multi-dynamic network utilizing both strong and weak hydrogen and disulfide bonds to develop a biobased polyurethane elastomer (PBES-U, prepared from biobased monomers such as itaconic acid, sebacic acid, etc.), featuring a cross-linked network capable of cryogenic self-healing, superior toughness, and reprocessability. This elastomer extends to 1100 % of its original length, achieving 90 % self-healing efficiency at temperatures down to -10 degrees C due to the low glass transition temperature (Tg, -30 degree celsius) achieved by modulating the flexibility of chain segments. Consequently, a bio-based TENG (LS-TENG) was produced using this elastomer as a positive friction layer through a dynamic interfacial interlocking method. The results reveal that LS-TENG achieves a notable power density of 12.2 mW/ m2, an output voltage reaching 160 V, and a 98 % output voltage recovery post-low-temperature self-healing. Furthermore, a non-contact LS-TENG-based monitoring system was developed with significant potential for applications in battlefield sensing, wildlife monitoring, and intelligent driving.