“…The triboelectric nanogenerator (TENG) based on the coupling of contact electrification and electrostatic induction was invented by Prof. Wang and his team . Due to its simple working mechanism and fabrication process, low cost, and efficient energy conversion, the TENG has been developed for micro/nano power sources, , self-powered sensing, − blue energy, − and high-voltage power sources. , Among them, the liquid–solid triboelectric nanogenerator has received extensive attention, and it has been used for motion sensors, , chemical sensors, − microfluidic actuators, , corrosion protection, , level gauges, − and so on. , For instance, Zhao et al . developed prototypes of a drainage bottle droplet sensor and a smart intravenous injection monitor based on the superhydrophobic liquid–solid contact TENG .…”