Flexible piezoelectric nanogenerator based on Ti3C2Tx-coated electrospun PVDF–TrFE nanofibers

Abstract

This study presents the development of a flexible piezoelectric nanogenerator based on electrospun PVDF–TrFE nanofibers coated with Ti₃C₂T_x MXene. The device is designed to harvest ambient mechanical energy for self-sustaining systems, addressing the limitations of conventional piezoelectric materials. We report the synthesis of Ti₃C₂T_x MXene, a novel 2D nanomaterial known for its high electrical conductivity and abundant surface terminations, which facilitate hydrogen bonding interactions with the dipoles of PVDF–TrFE molecular chains. The Ti₃C₂T_x MXene nanosheets were synthesized and deposited as a thin layer onto PVDF–TrFE nanofiber mats via a vacuum-assisted filtration method. This coating enhances the net dipole moment around the MXene surface, predominantly aligning it along the z-axis. The electrospinning process was optimized to produce uniform PVDF–TrFE nanofibers with a high β-phase content, which is crucial for enhanced piezoelectric performance. The MXene coating significantly improved the electrical properties of the nanofibers, resulting in a nanogenerator with an output voltage 20 times higher than that to pure PVDF–TrFE. This innovative composite demonstrates great potential for applications in self-powered wearable and portable devices.