Enhancing β-phase and crystallization speed of poly(vinylidene fluoride) thin film by doping with graphene oxide

High β-phase poly(vinylidene fluoride) (PVDF) thin films were spin-coated from a solution doped with small amounts of graphene oxide (GO). The effects of GO on the characteristics of PVDF were examined by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction measurements, and differential scanning calorimetry. The main crystal structure of GO doped PVDF thin film was β-phase and the grain size of thin film decreased from 15 μm (pure PVDF) to 3 μm (GO doing). The optimized annealing temperature of PVDF/GO thin film was identified to be 75 °C. At room temperature, the permittivity of PVDF thin film increased from 5.3 to 6.2 at 1 kHz. Further, the isothermal crystallization kinetics of PVDF/GO thin films demonstrated that GO could serve as an effective nucleating agent to promote the crystallization of PVDF.