Development of KNNLTS–PVDF-based flexible piezoelectric generator for energy-harvesting application

In the present work, a flexible piezoelectric generator (PEG) based on (Li, Ta, Sb) modified (K, Na) NbO 3 (KNNLTS)/poly(vinylidene fluoride) (PVDF) flexible composite film is fabricated. The prepared films are characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The addition of KNNLTS in the PVDF polymer matrix has resulted in the enhancement in the ferroelectric, piezoelectric, dielectric and piezoelectric output performance. The maximum generated open circuit peak-to-peak voltage from the PVDF/KNNLTS PEG was 36.58 V, which is almost four times higher than the voltage obtained using pure PVDF. The performance of the PEG is also tested under different human body motions, such as fist beating, elbow bending, and quenching and fist opening, which shows the maximum voltage of 5.48, 4.12 and 1.72 V, respectively. The present work demonstrated that high-performance PEG can be developed by modifying KNN ceramics by suitable dopants that can be used in self-powered and wearable devices. Graphical abstract