Structural, optical, morphological and thermal properties of PEO/PVP blend containing different concentrations of biosynthesized Au nanoparticles

Casting technique was used for preparation of polyethylene oxide (PEO)/polyvinyl pyrrolidone (PVP) (70/30 wt.%) films filled with different concentrations of gold nanoparticles (Au NPs). X-ray diffraction (XRD) pattern proved the semi-crystalline nature of the pristine and filled polymer blend. Fourier transform infrared (FT-IR) and Ultraviolet/Visible (UV/Vis.) analyses were used to retrace the structural and optical changes with increasing Au content. UV/Vis. analysis spectroscopy was utilized to calculate the optical properties such as optical energy gap Eg, refractive index n and Urbach energy Eu for blend/Au nanocomposite films. Scanning electron micrograph (SEM) suggested the dependence of morphological structure on filling level and the surface morphology changed from rough to smooth. Transmission electron microscope (TEM) micrographs showed that the size of Au NPs was increased with continuous filling in PEO/PVP. Thermogravimetric analysis (TGA) was performed to investigate the thermal stability for nanocomposite films. Keywords: PEO/PVP, Au NPs, FT-IR, Optical properties, TGA