Comparison of piezoelectric energy harvesting performance using silicon and graphene cantilever beam

Abstract

A bulky battery is often an obstacle in microelectromechanical systems design. Not only does it occupy large space, but also contributes to environmental pollution. Thus, piezoelectric energy harvester presents as an eco-friendly alternative power source. A piezoelectric energy harvester with graphene as base layer with different thickness is modeled using finite element simulations. Frequency response analysis is performed for a better understanding of its performance. From the result, higher thickness gives better Q-factor and figure of merit (FOM). A 200 nm of ZnO layer and graphene layer gives a Q-factor and FOM of 3.4 times higher than silicon and also a larger bandwidth by a factor of 1.1. In general, it is shown that the replacement of silicon with graphene had reduced energy loss by improving the efficiency of mechanical energy transfer in piezoelectric energy harvester.