Improved dielectric and mechanical performance in three phase poly(vinylidene fluoride) composites with hybrid fillers of MXene and g-C3N4

In this study, MXene and graphitic carbon nitride (g-C 3 N 4 ) nanosheets were introduced into Poly(vinylidene fluoride) (PVDF) matrix to fabricate ternary composites with a well balanced dielectric constant and dielectric loss. The g-C 3 N 4 /MXene hybrid fillers were prepared via solution blending, followed by the fabrication of g-C 3 N 4 /MXene/PVDF composite films through solution casting. At 1 kHz, the composite film containing 6 wt% g-C 3 N 4 exhibited a high dielectric constant of 56.2 and a low dielectric loss of 0.12. The g-C 3 N 4 nanosheets effectively inhibited the self-stacking of MXene nanosheets, thereby suppressing the formation of conductive pathways and reducing the dielectric loss of g-C 3 N 4 /MXene/PVDF composites. Additionally, g-C 3 N 4 /MXene hybrid fillers enhanced interfacial polarization, promoted the formation of microcapacitor structures within the composites, and improved mechanical properties. The storage modulus of the composite film containing 6 wt% g-C 3 N 4 reached 1230 MPa, which is 2.12 times that of pure PVDF. This work presents a promising strategy for developing PVDF-based dielectric composites with superior dielectric performance.