Flexible textured MnO2 nanorods/PVDF hybrid films with superior piezoelectric performance for energy harvesting application

To date, the fabrication of high-performance flexible energy harvesters/nanogenerators based on piezoelectric poly(vinyldene fluoride) (PVDF) is of great concern due to their huge potential to realize full-flexible self-powered electronics. Herein, in this work, we report a flexible piezoelectric nanogenerator (PNG) based on a textured hybrid film consisting of PVDF and manganese dioxide (MnO2) nanorods. It is found that the combination of MnO2 and PVDF can notably facilitate the formation of piezoelectric phase, increase the crystallinity and promote the polarization level, inducing dramatically strengthened piezoelectric and output activity for PVDF. Additionally, the addition of MnO2 has the effect of significantly enhancing the mechanical property while slightly increasing dielectric constant of nanocomposites, which are advantageous to further harnessing the output enhancement. With an optimal loading of 1.0 wt% MnO2, the piezoelectric coefficient (d(33) approximate to 38 pC/N) and correspondingly output response of hybrid films reached the peak. For instance, under the d(33) working mode, an output voltage of 3.2 V can be achieved in hybrid films while that of PVDF is only 1.7 V.