Evaluation of the performance of a piezoelectric nanowire-based composite microgenerator

A vertically integrated nanogenerator (VING) refers to the new generation of mechanical energy harvesting devices: arrays of piezoelectric and semiconducting nanowires are grown perpendicularly to a substrate and appropriate electrodes enable the charges circulation through an external electrical load. In this letter, an equivalent circuit of VING is proposed. This model takes into account the effect of the polymer matrix that surrounds the nanowires lattice on the electromechanical behaviour of the generator. The active part of the material is then seen as a 1-3 piezocomposite. Simulations were made to study the VING performance in a context of body movement energy harvesting. In particular, it is shown that the nanowires density and the nature of the polymer have an impact on the nanogenerator volumic power density.