Transparent Piezoelectric Polymer-Based Materials for Energy Harvesting and Multitouch Detection Devices

Abstract

Energy harvesting devices allowing to recover wasted energy from the environment are \nincreasingly developed. Mechanical energy is one of the most interesting sources of \nenergy for energy harvesting and piezoelectric materials present excellent overall \nproperties for the scavenging of that energy. Piezoelectric polymers and, in particular, \npolyvinylidene fluoride (PVDF), show appropriate mechanical properties for large \namplitude movements, higher piezoelectric coefficients, transparency, and be easily \nintegrated intro devices. \nA transparent piezoelectric energy harvesting device has been developed with screen \nprinted transparent (72%) and conductive (42 Ω/sq) electrodes on PVDF sheets with a \nd33= -23 pC/N, generating about P~ 12 μW and P~ 8 μW under pressing and bending \nmodes, corresponding to an energy per cycle of E~ 37 nJ and E~ 55 nJ, respectively. \nThe piezoelectric energy harvesting characteristics of the materials was theoretical \nevaluated and the applicability of the materials for touch detection demonstrated.