Development of high-performance flexible piezoelectric nanogenerator using Yb-doped ZnO/PVDF-HFP polymer nanocomposite

In recent years, rare earth doped metal oxide materials have emerged as a great potential in optoelectronic and flexible nanogenerator applications. We have synthesized pure and Yb-doped ZnO with wet chemical co-precipitation method. FESEM analysis revealed change in the morphology attributed to the influence of Yb 3+ ions on the ZnO. Ferroelectric hysteresis loop provides evidence of defect-induced ferroelectric behaviour in Yb-doped ZnO with remnant polarization (P r = 0.04 μC/cm 2 ) and coercive field (E c = 64.64 kV/cm). The fabricated Yb-doped ZnO/PVDF-HFP composite PENG was tested by electromechanical tapping at a load of approximately 0.02 kgf to obtain an output voltage of range 18 V to 20 V. In addition, PENG was analysed against a range of resistance and the maximum power density of ∼195.16 mW/cm 3 was obtained with an active contact area of 2.25 cm 2 and volume ∼0.02 cm 3 . The cyclic stability of the fabricated Yb/ZnO PENG was further evaluated under prolonged mechanical deformations at 20 Hz for 2000 s, corresponding to approximately 40,000 mechanical tapping cycles. The developed flexible PENG was able to light up 10 commercial light emitting diodes indicating applications in a high-performance flexible nanogenerator.