Flexible Piezoelectric Nanogenerators Based on P(VDF-TrFE)/CsPbBr₃ Quantum Dot Composite Films

Benefiting from high flexibility and lightweight characteristics, flexible piezoelectric nanogenerators (PENGs) have the potential to become a ubiquitously available and sustainable alternative source of energy. Herein, we fabricated a poly(vinylidene fluoride–trifluoroethylene) (P(VDF-TrFE)) PENG doped with CsPbBr3 quantum dots (QDs), which reveals a remarkable enhancement in piezoelectric output performance. PENGs doped with 0.3 wt % of CsPbBr3 QDs exhibit an optimized piezoelectric coefficient from 15.5 to 24.5 pC N–1, and the corresponding open-circuit voltage and short-circuit current are enhanced by 2.5 and 2.2 times, respectively, thanks to the increased β-phase content of the P(VDF-TrFE). The composite PENGs are sensitive to several human movements like bending, finger touch, and wind blowing, showing great potential for application in self-powered sensing and energy harvesting. Moreover, fatigue test under continuous mechanical stimuli, and after long periods of rest (up to 2 months), demonstrates the PENG capabilities to be used as a robust mechanical energy harvester.