A self-powered hydrogen leakage sensor based on impedance adjustable windmill-like triboelectric nanogenerator

With the development of fuel cell vehicles, the hydrogen leakage detector is urgent to satisfy the safety requirements of the vehicles with low power consumption. In this work, a self-powered hydrogen leakage detector based on impedance adjustable windmill-like triboelectric nanogenerator (WL-TENG) has been demonstrated. It could harvest wind energy during the driving of hydrogen fuel vehicle to power the whole sensing system. The inherent impedance and matching region of WL-TENG can be tuned effectively by adjusting the center angle of the windmill plate. The resistance of the Pd/ZnO nanorods based hydrogen sensor changes from 300 kΩ to 60 kΩ under pure air atmosphere to 1000 ppm H2. Then, a matching WL-TENG with 3° center angle was series connected to H2 sensor to construct the self-powered H2 sensing system. Finally, by introducing 150 kΩ divider constant resistor, the voltage across it increases from ~15 V to ~60 V with the H2 concentration increasing from 0 to 1000 ppm. The output voltage of WL-TENG varies with the variable working states of the gas sensor and then directly reflects on the on/off status of the LEDs parallel connected to the divider resistor. This work contributes to the development of impedance matching theory of TENG and further expand its application on self-powered sensing system.