Ferrofluid-based triboelectric-electromagnetic hybrid generator for sensitive and sustainable vibration energy harvesting

Abstract

A vibration energy harvester that utilizes a liquid medium has been the subject of active research recently given its advantages of shape adaptability, scalability, and durability. In this work, a ferrofluid-based vibration energy harvester with a hybrid triboelectric-electromagnetic operating mechanism is proposed for the first time. The ferrofluid suspension solution is made with water and magnetic nanoparticles. Electrostatic induction between the polymer sidewall and the solvent water activates a triboelectric generator component, while electromagnetic induction between the suspended magnetic nanoparticles and an outer coil activates the electromagnetic generator component. Experimental results for the ferrofluid-embedded hybrid energy harvester showed an extremely low threshold amplitude and a wide operating frequency range, both of which can be particularly advantageous for harvesting subtle and irregular vibrations.