Hybrid tribo-piezoelectric microgenerator for mechanical energy harvesting

In the present study, a hybrid triboelectric/piezoelectric generator was proposed to combine simultaneously the piezoelectric and triboelectric effects to improve the device's performances. When subjected to the shaker motion, the hybrid generator delivers an open circuit voltage of 318 V, a short-circuit current of 4.95 μA and a maximum power of 349 μW dissipated in a load resistance of 40 MΩ under the application of a force of 8.5 N at a frequency of 2 Hz after rectification by two diode bridges. A capacitor of 80 μF capacitance was charged with the piezoelectric, triboelectric and hybrid systems with vibrating shaker. Thanks to the triboelectric-piezoelectric hybridization, the charging time is reduced by 74 % compared to the piezoelectric system alone and 39 % compared to the triboelectric system alone. Finally, a temperature sensor was powered by a 1 mF capacitor charged to 4.5 V by the hybrid tribo/piezoelectric generator.