Optical and structural properties of polyvinylidene fluoride (PVDF) / reduced graphene oxide (RGO) nanocomposites

Nanocomposites consisting of polyvinylidene fluoride [PVDF] and reduced graphene oxide [RGO] were fabricated by solution casting method. TEM image of the RGO exhibits paper-like structure with single or very thin layers. FTIR and XRD revealed that the structure of PVDF is strongly affected upon the addition of RGO and the β-phase fraction was found to increase on the expense of α-phase. DSC data indicates that increasing the RGO content decreases the nanocomposites crystallinity. Optical properties were investigated in the wavelength range (200-800 nm). The effect of RGO content on the optical band gap was studied. Doppler broadening parameters (S and W) of 511 keV annihilation radiations were measured. A reasonable correlation was found between S-parameter, the crystallinity and the optical band gap. Doppler broadening parameters provide an explanation of the positronium formation as well as the type and concentration of defects in the investigated composites.