Computer aided molecular modeling of the piezoelectric properties of ferroelectric composites on the base of polyvinylidene fluoride with graphene and graphene oxide

Molecular modeling of ferroelectric composites containing polyvinylidene fluoride (PVDF), graphene (G) and/or graphene oxide (GO), was performed using the semi-empirical quantum approximation PM3 in the HyperChem software package. The piezoelectric properties of the composites were analyzed and compared with the experimental data obtained for thin films containing poly(vinylidene-fluoride-trifluoroethylene) with graphene oxide (P (VDF-TrFE)/GO). A qualitative agreement was obtained between the simulation results and the experimental measurements of the piezoelectric coefficient, its decrease in the presence of G or GO was revealed. When models containing one or more layers of graphene with 54 carbon atoms were investigated, it was found that the average piezoelectric coefficient was reduced to -9.8 pm/V for the one-sided PVDF/G model and to -18.98 pm/V for the two-sided sandwich model G/PVDF/G in compare with the calculated piezoelectric coefficient for pure PVDF (-42.2 pm/V). After computer modeling for models incorporating one or more layers of 96 carbon atoms in the oxide graphene, it was found that the piezoelectric coefficient was reduced to a value of -14.6 pm/V for a one-sided PVDF / GO model and to a value of -29.8 pm/V for a two-sided sandwich model GO/ PVDF/GO compared to the piezoelectric coefficient for pure PVDF.