Flexible piezoelectric sensor based on PVP-modified BaTiO₃/MXene/PVDF-TrFE composite film for wearable applications

Flexible piezoelectric sensors have attracted extensive interest from both domestic and international researchers in wearable devices and electronic skin. This study proposes to introduce polyvinylpyrrolidone (PVP) and two dimensional transition-metal-carbon/nitride (MXene) to solve the agglomeration phenomenon and insufficient polarization between poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) and barium titanate nanoparticles. PVP@BaTiO₃/MXene/PVDF-TrFE piezoelectric films were prepared by surface modification method and solvent substitution method, and the output voltage of the films was enhanced by 241.80% compared with that of PVDF-TrFE films. The piezoelectric sensors were prepared using films with a thickness of 0.03 mm for testing and analysis. The results demonstrate that the proposed sensor exhibits excellent linearity characteristics within the pressure range of 0.1N to 18N, with a sensitivity of 182.17 mV/N and a response time of 40ms. Furthermore, the sensor consistently maintains stable output voltage in an extensive durability test involving 10,000 pressing cycles. The sensor has been demonstrated to effectively recognize the mass change of an object. Furthermore, the integration of these sensors into an array facilitates the effective recognition of the sliding signal, thereby enabling the realization of complex pressure distribution detection. The sensor shows considerable promise for application in fields such as wearable devices.as wearable devices.