Preparation and studies of MXene@PDA/PVDF composites with improved dielectric properties

MXene has garnered extensive attention in the preparation of polymer dielectric materials due to its outstanding electrical conductivity. However, high dielectric loss has hindered the application of such polymer-based composites. In this study, MXene/PVDF composites were prepared with polyvinylidene fluoride (PVDF) as the matrix and two-dimensional nanosheets (Ti3C2Tx MXene) as fillers. To mitigate dielectric loss, MXene was adorned with a polydopamine (PDA) layer. Results showed that compared to MXene/PVDF composites, MXene@PDA/PVDF composites exhibit lower dielectric loss. At 103Hz, the dielectric constant of 2wt.% MXene@50%PDA/PVDF composite (50% PDA relative to the mass of MXene) is 12.8, showing a 1.5-fold that of pure PVDF. However, it boasts a mere dielectric loss of 0.017, signifying a remarkable reduction of 57.4% when compared to the MXene/PVDF composite. The 12wt.% MXene@25%PDA/PVDF composite (25% PDA relative to the mass of MXene) demonstrates a dielectric constant of 101.4 at 103Hz. It boasts a dielectric loss of 0.377, signifying a reduction of 36.1% compared to the MXene/PVDF composite. Composites with excellent dielectric properties can be prepared by the addition of MXene@PDA into PVDF.