Nano-scale energy harvester of piezoelectric/piezomagnetic structures with torsional mode

This work presents a nano-scale cylindrical shell serving as an energy harvester with piezoelectric/piezomagnetic materials. Based on the torsional mode, the surface effects on the properties of the energy harvester are investigated. The results show that the capability of the energy harvester can be enlarged by adjusting the surface material constants. The power density will grow with the increasing of the residual surface stress. Moreover, the performance of the energy harvester can be improved by reducing the total height of the cylindrical shell. The larger height ratio of the piezoelectric to piezomagnetic materials will also lead to greater power density. This paper presents that the energy harvester can be made of nano-scale composite structures, which would be helpful for its application to nano technology.