Fabrication of piezoelectric nanogenerator using 3D-ZnO nanosheets and optimization of charge storage system

In this research work, an easy and novel approach is adopted for fabrication of piezoelectric nanogenerator (PENG) based on 3D-ZnO nanosheets (NSs). The 3D-ZnO NSs were fabricated on anodic aluminium oxide (AAO) membrane. The NSs were separated from Al bottom electrode by AAO layer and Cu thin sheet was used as top electrode. The 3D-ZnO NSs were investigated by FE-SEM, XRD, and Raman spectroscopy. A mechanical force of 3 kgf with 6 Hz was applied on PENG that generated an output voltage of 895 mV, and current of 446 nA with maximum power density 50 nW/cm(2). The PENG was then utilized to charge load capacitors and found that the maximum energy could be stored at an optimum load capacitance (C-L) of 10 nF in 600 s. The 3D ZnO NSs enhanced stability, and robustness of PENG. The fabricated PENG was continuously operated for 3 h without any degradation in output performance.