Fabrication and dielectric properties of oriented polyvinylidene fluoride nanocomposites incorporated with graphene nanosheets

The morphology and microsctructure of layered graphene nanosheets/polyvinylidene fluoride (GNS/PVDF) nanocomposites fabricated by a facile and effective process are investigated. The graphene nanosheets were well dispersed and highly oriented in the matrix due to the unique preparation process. The morphology and microstructure were investigated. The results showed that the nanocomposites exhibited a much lower percolation threshold (1.29 vol%) than materials filled with carbon nanotubes. More importantly, a high dielectric constant of 63 (100 Hz) was obtained when the concentration of graphene was 1.27 vol% and it was 9 times higher than that of pure PVDF. The dielectric performance of the nanocomposites can be attributed to the homogeneous dispersion of GNS, well-aligned GNS, and resulting microcapacitor structure. An orientation mechanism for the well-aligned microstructure is proposed.