Structural and optical properties of PVDF/GO nanocomposites

Abstract

Graphene oxide (GO) was prepared through the modified Hummar’s method. The polymer nanocomposites (PNC) composed of polyvinylidene fluoride (PVDF) and GO, with different wt% of GO were prepared, following the solution casting method in the form of thin films. The micro/nano-structural features and the optical properties of the PNC have been studied. The formation of GO was confirmed through FTIR and Raman spectra analysis. The microstructure, homogeneity, extent of agglomeration and the elemental composition of the PNC were found through the FESEM, energy dispersive analysis of X-rays and the elemental dot mapping, confirming excellent homogeneity of the PNC films. The optical properties like absorbance, refractive index, the extinction co-efficient and the dispersion behavior were investigated with the help of UV-visible spectrophotometer and spectroscopic ellipsometer respectively. The results reveal an increase in absorbance with the increase of weight % of GO in the PNC, attributed to higher electrical conductivity and surface area of GO. The optical parameters (e.g., refractive index, extinction coefficient, etc.) in the visible region show large variation as a function of weight % of GO due to PVDF/GO interaction and optimized properties was found to be for the 5% PNC, making it suitable for various optical applications.

Keywords:

• Graphene oxide
• microstructure
• optical properties
• FTIR and Raman spectra
• ellipsometry

Acknowledgments

The authors would like to acknowledge the Sophisticated Instrumentation Centre of Dr. Harisingh Gour Vishwavidyalaya for providing the experimental data.