Enhanced Output Performance of NaNbO ₃ /P(VDF-TrFE)-Based Piezoelectric Nanogenerators by Femtosecond Laser Surface Modification for Bioenergy Harvesting and Human Motion Monitoring

The widespread application of Internet of Things (IoT) technology promotes the miniaturization and intelligent development of electronic devices, posing significant challenges to the effective microenergy harvesting and optimization of self-powered devices. Here, we present NaNbO3/P(VDF-TrFE)-based piezoelectric nanogenerators (NP-PENGs) based on femtosecond laser surface modification for bioenergy harvesting and human motion monitoring. In this study, NaNbO3 nanoparticles are synthesized by liquid-phase pulsed laser ablation, and the phase structure of P(VDF-TrFE)-based composite materials is processed by femtosecond laser surface modification. The aim is to establish a synergistic system of nanoparticle induction and laser precise control to enhance the content of the β-phase in three dimensions from nucleation initiation, orientation control, and structural stability. Importantly, the output potential of flexible P(VDF-TrFE) and 5 wt % NaNbO3/P(VDF-TrFE)-based PENGs after femtosecond laser processing can reach 26.1 V (36% improvement) and 40 V (52% improvement), respectively. Furthermore, the flexible PENG exhibits great stability under cyclic mechanical stress for 3000 s and successfully powers 20 LEDs. By attaching the NP-PENG to various parts of the human body, it can not only precisely sense human motion status but also real-time monitor the output voltage changes. This study provides an efficient and straightforward method for achieving precise control of high β-phase content and high-performance PENGs, and it demonstrates its enormous potential in the field of intelligent wearable devices.