Self-Powered Wireless Monitoring of Obstacle Position and State in Gas Pipe via Flow-Driven Triboelectric Nanogenerators

Triboelectric nanogenerator (TENG) has attracted increasingly attention in a new energy field. However, it is still a huge challenge for TENG to transmit electricity or be self-powered sensing without hard wires, which can reduce the efficiency of power generation and further cause inconvenience for connecting device. Here, a flow-driven wireless TENG for efficient power transmission, ultrasensitive distance sensing, and obstacle monitoring in the gas pipe is reported. The wireless TENG can generate a voltage/current signal of about 121.0 V/4.4 mu A at the receiving distance of 1.5 cm with a wind speed of 18.0 m s(-1). When the distance is increased to 10.0 cm, the output voltage can be decreased to 8.0 V with a sensitivity of 92% owing to the decrease of induced charges on receiving electrodes. The relationship that the output voltage decreases with increasing the receiving distance has been confirmed, suggesting the possibility of the wireless TENG as a self-powered distance sensor. Moreover, by installing several wireless TENGs uniformly in a gas pipe, the position and specific placement state of an obstacle in gas pipe can be effectively monitored with the self-powered way.