Simulation study of ZnO nanorod geometry for the development of high-performance tactile sensors and energy harvesting devices

Abstract

ZnO exhibits an excellent piezoelectric response and can transduce mechanical energy into electrical signals by applying pressure. In particular, vertically aligned ZnO nanorods were thought to be of great importance because of their higher value of piezoelectric coefficient along the z-direction. In this study, various geometries of ZnO nanorods are explored and their effect on the strength of piezoelectric output potential is simulated using COMSOL Multiphysics software. The simulation results show that out of many geometries and inclinations of ZnO nanorods, the highest piezoelectric output is demonstrated by the inclined ZnO nanorods due to the application of higher torque force or shear stress in similar applied force. The high torque force or shear stress at 60⁰ orientation and optimized contributions from all the piezoelectric coefficients resulted in a high piezoelectric output potential close to 215 mV which is much higher than the vertically aligned ZnO nanorod which is approximately 25 mV.