A liquid metal-based triboelectric nanogenerator as stretchable electronics for safeguarding and self-powered mechanosensing

In recent years, high performance triboelectric nanogenerator (TENG) shows distinguished energy-harvesting property which guarantees its potential applications as a power source. However, collision and harsh impact, occurred in daily life, always injure human beings. Developing novel multifunctional TENG with self-powered mechanosensing and protection properties from violent impact is an urgent and meaningful work. Here, a multifunctional TENG with energy-harvesting, safeguarding and self-powered force-sensing properties was fabricated by assembling shear stiffening gel/polydimethylsiloxane (SSG/PDMS) matrix with GaInSn liquid metal. Operating at 10 Hz, TENG with a size of 50 x 50 x 4 mm(3) obtains an output voltage of 35.72 V, current of 5.10 mu A, and maximum output power of 182.17 mu W. In addition, TENG device generates enhanced output power of 323.97 mu W under tensile strain of 80%. Besides harvesting mechanical energy, TENG with fast stimuliresponsive character, has been proven as a self-powered sensor to monitor varieties of physiological movements. More importantly, the TENG device with high damping property enables to dissipate 66.43% of external impact force which provides favorable protection effect. Correspondingly, the distinguished output voltage signals can also reveal and assess different impulsive loads. This work proposes a multifunctional TENG device with energy harvesting, and utilizing the flexible TENG for safeguarding and self-powered mechanosensing.