The effect of reduced graphene oxide intercalated hybrid organoclay on the dielectric properties of polyvinylidene fluoride nanocomposite films

In present investigation, reduced graphene oxide sandwiched organoclay (Clay@r-GO) was introduced as conductive nanofillers to promote the electroactive β-phase as well as conducting network within polyvinylidene fluoride (PVDF) via solution casting technique. The composition of Clay@r-GO nanohybrid filler was formulated in the weight ratio of 1: 20 of graphene oxide and organoclay after observing the independent contribution of r-GO and organoclay to the dielectric property of PVDF. PVDF/Clay@r-GO nanocomposite films were designed with various wt% of Clay@r-GO filler. The fabricated PVDF/Clay@r-GO nanocomposite film was characterized with SEM, TEM, FTIR and XRD. Electron microscopic results revealed that only 5 wt% of Clay@r-GO hybrid nanostructures was effective to inhibit the formation nonpolar α crystal, whereas; FTIR analysis showed the ~ 80% transformation of β-phase in PVDF/Clay@r-GO nanocomposite film with incorporation of only 2 wt% Clay@r-GO hybrid filler. With 2 wt% of nanohybrid filler, thermal stability of PVDF/Clay@r-GO nanocomposite film was highly improved with a char residue of 41.37% at 700 °C. Dielectric study reveals that only 2 wt% hybrid nanofillers was effective to impart high dielectric permittivity (ɛ`~102 at 1 Hz) as well as low dielectric loss (<1), whereas; a optimum permittivity (ɛ`~ 433 at 1 Hz) is observed for 15 wt% loading. Therefore, the fabricated PVDF/Clay@r-GO nanocomposite film may be used as advanced dielectric materials for real life application.