MWCNTs/C60 “Grape-like” Nanostructures for Enhancing Piezoelectric Performance in PVDF Nanofibers through Constructing Localized Conductive Domains

Polyvinylidene fluoride (PVDF) piezoelectric nanofibers gain significant attention for flexible electronic devices, yet their low piezoelectric conversion efficiency remains a critical barrier to broader application. In this study, multiwalled carbon nanotubes (MWCNTs) are combined with fullerene (C60) to form a distinctive “grape-like” nanostructure (MC), which is then embedded into the PVDF matrix via electrospinning to produce PVDF/MC composite nanofibers. The incorporation of MC increases the β-phase content of the PVDF nanofibers by 11.07%, enhancing their piezoelectric properties, and also acts as localized conductive domains and stress concentration centers, synergistically boosting the output performance of the piezoelectric devices. Consequently, piezoelectric devices based on PVDF/MC-3 wt % composite nanofibers exhibit voltage and current outputs 559.1% and 1382.8% higher than those of pure PVDF, respectively. This innovative strategy of leveraging “grape-like” nanostructures to enhance PVDF’s piezoelectric performance represents a promising pathway toward achieving efficient energy conversion in piezoelectric materials.