Microstructure, electrical, and transport properties: Graphene oxide reinforced poly (vinyl alcohol)-chitosan based polymer blend electrolytes

Abstract

In this present work, graphene oxide (GO) was synthesized using modified Hummer’s method. The polyvinyl alcohol-chitosan (PVA-CS) and GO doped solid polymer blend nanocomposite film were prepared using solution cast method. FTIR study shows the shift in characteristic peaks of the pure polymer blend due to doping and a new peak is observed at 1734 cm⁻¹ in GO (5 wt%) doped polymer composites. Optical absorption band is shifted from 206 nm to 237 nm with an increase in GO concentration to 5 wt% and the E_g value decreased from 4.69 eV to 2.32 eV for 5 wt% GO concentration. X-ray diffraction study indicates the crystalline nature of the PVA-CS increases with GO concentration. SEM images show the surface roughness of PVA-CS increases upon GO doping. Impedance plots revealed that the resistive component and the relaxation time decreases with GO concentration. The highest conductivity of 2.83 X 10^-4 Scm⁻¹ is observed for 5 wt% GO concentration. The transport property shows that the ions are the majority conducting charge carriers in this composites.