Molecular dynamics simulations of ferroelectricity in P(VDF-TrFE)

Poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) is a derivative of polyvinylidene fluoride (PVDF), known for its excellent ferroelectric properties, optical characteristics, chemical stability, and flexibility, making it a promising material for applications in electronic devices. In this study, the polarization switching mechanism of the β-phase of P(VDF-TrFE) is investigated using the polarized crystal charge method, along with molecular dynamics simulations. The simulation results show that the saturation polarization value is approximately 5.3 μC/cm², and a coercive field of around 0.5 V/nm is required to switch its polarization states. By fitting the polarization reversal curve with the Kolmogorov–Avrami–Ishibashi model, it is observed that the data in the asymptotic and switching regions closely align with the predictions of the model, and the Avrami index n consistently ranges between 1 and 2. The polarization reversal is completed within approximately 10 ps, demonstrating high-speed dynamic behavior. Additionally, we predict that the ferroelectric phase transition occurs between 420 K and 430 K, with stable polarization performance maintained over a wide temperature range, which is consistent with experimental results.