Tuning the Electromechanical Response of P(VDF-TrFE)/ZnSnO<sub>3</sub>-Based Binary Piezoelectric Composites for Biomechanical Energy-Harvesting and Self-Powered Mechanosensing
Payel Maiti, Abhishek Sasmal, A. Arockiarajan, Rahul Mitra
Abstract
Here, we develop poly((vinylidene fluoride)-trifluoroethylene) P(VDF-TrFE)-based binary piezoelectric composites by incorporating piezoelectric ZnSnO 3 (ZS) nanoparticles (with varying concentrations up to 15 wt %) into its matrix. The dielectric permittivity of pristine P(VDF-TrFE) has been found to increase gradually with the increase in ZS filler concentration (from a value of 10.98 for pristine P(VDF-TrFE) to 13.72 for 15 wt % ZS-loaded P(VDF-TrFE) (15PTR) at 1 kHz frequency), which has been explained on the basis of dipolar and space charge polarization. The increase in dielectric loss tangent and lossy nature of ferroelectric hysteresis loops of the samples upon gradually increased filler loading also have suggested the significant effect of increased space charge polarization. The nanohardness and elastic modulus of the samples have also been found to be increased with increasing filler concentration (from 43 MPa and 1.44 GPa for neat P(VDF-TrFE) to 216 MPa and 2.98 GPa for 15PTR, respectively). All of these results have been correlated with the output mechanical energy-harvesting performance of the composites. The 10PTR (10 wt % ZS-loaded P(VDF-TrFE))-based nanogenerator device has shown very high output performance in terms of open-circuit voltage (∼48 V) and power density (∼70 μW/cm 2 ) and hence has been used for versatile biomechanical energy-harvesting and self-powered mechanosensing. The optimized performance of the 10PTR device has been explained on the basis of several parameters like dielectric permittivity, mechanical property, and piezoelectric coefficient. The periodic and static pressure sensing activity, vibration-sensing performance, and posture sensing activity of the device have been demonstrated here elaborately.