Influence of Nano-CeO₂ and Graphene Nanoplatelets on the Conductivity and Dielectric Properties of Poly(vinylidene fluoride) Nanocomposite Films

Abstract

Novel three-phase polymer nanocomposites (PNCs) based on cerium oxide (CeO 2 ) nanoparticles (NPs) and graphene nanoplatelets (GNPs) incorporated in a poly(vinylidene fluoride) (PVDF) matrix were formulated using a solution-casting approach. To understand the structural and morphological features of PVDF/CeO 2 / GNP nanocomposites (NCs), scanning electron microscopy (SEM) and highresolution transmission electron microscopy (HRTEM) analyses were accomplished. The PVDF/CeO 2 /GNP NCs displayed improved thermal stability which resulted from strong bonding between GNPs and CeO 2 NPs and restriction of the polymer chain movement. The introduction of CeO 2 NPs and GNPs within the PVDF matrix and good synergy between CeO 2 NPs and GNPs led to variable mechanical properties of the prepared NCs. The PVDF/CeO 2 /GNP NCs portrayed reduced thermal stability, which could be due to the increased mobility of PVDF chains imposed by GNPs leading to the formation of volatile degradation products. Moreover, PVDF/ CeO 2 /GNP NCs exhibited good electrical conductivity and high dielectric permittivity. The obtained dielectric permittivity value for the PVDF/CeO 2 /GNP NCs was 3-fold greater than PVDF/CeO 2 NCs, making these novel tertiary composite materials a probable candidate for energy-storage applications.