Tunable piezoelectric performance of flexible PVDF based nanocomposites from MWCNTs/graphene/MnO2 three-dimensional architectures under low poling electric fields

Till date, developing flexible poly(vinylidene fluoride) (PVDF) based nanocomposites with high piezoelectric performance is of great interest for constructing sensors, transducers and energy harvesters. Herein, we proposed a simple strategy to build a three-dimensional hybrid nanostructure consisting of manganese dioxide/graphene/Multi-walled carbon nanotubes (MnO2/graphene/MWCNTs) to enhance the piezoelectric performance of PVDF. By tailoring the MnO2 mass loading of hybrids, tunable breakdown strength and piezoelectric performance can be achieved in the nanocomposites. Meanwhile, employing this hybrid can reduce the high poling electric field (>100 MV/m) required for PVDF to induce good piezoelectric performance. With a relative low poling electric field (50-80 MV/m), high piezoelectric coefficients d33 of 17-33 pC/N can be obtained in the nanocomposites, which are twice that of PVDF under the same poling conditions. For the first time, the potential of MWCNTs/graphene/MnO2 in fabricating nanocomposites with superior piezoelectricity and low poling electric field requirement is demonstrated.