Impedance Matching Effect between a Triboelectric Nanogenerator and a Piezoresistive Pressure Sensor Induced Self‐Powered Weighing

Abstract How to develop a simple and stable self‐powered force/pressure monitoring system has attracted extensive interests, yet it still faces intractable problems and challenges. As a mechanical force‐driven generator, the most straightforward application for triboelectric nanogenerator (TENG)‐based sensor is to directly monitor the external pressure. In this work, a self‐powered pressure monitor system is proposed by the conjunction of triboelectric and piezoresistive effects, in which a free‐standing disk‐shaped TENG (FD‐TENG) serves as an energy harvester, and a multiwalled carbon nanotube‐based flexible piezoresistive pressure sensor (PPS) works as a real‐time pressure monitor. The induced output voltage of the FD‐TENG is tuned by the working states of the PPS, which is responded to the external weight stimuli. Based on the impedance match between FD‐TENG and PPS, the self‐powered weighing system renders a voltage varying from 46.2 to 168.6 V in a range from 1 to 20 kg with a fast response/recovery kinetics (1.2 and 2.3 s) and good stability, which enable to directly reflect on the on/off status of appropriate amount LEDs powered by FD‐TENG. Finally, it is demonstrated to equip into a successive pedrail transportation system for monitoring the qualified/unqualified weight products.