Optical Properties of CuS Nanoparticles Embedded Polyvinyl Alcohol (PVA) Films

Abstract

The pristine poly(vinyl alcohol) and CuS nanoparticles with different concentrations (1 %-10 %) doped PVA films were prepared by solution casting method. The CuS nanoparticles were prepared by chemical precipitation; and XRD studies confirmed the formation of pure CuS nanoparticles with average size of 18 nm. The optical properties of pristine as well as doped PVA films were evaluated using UV-VIS-NIR spectroscopy. UV-VIS-NIR spectrum of CuS nanoparticles showed LSPR band in NIR region. The optical properties like absorption coefficient, bandgaps, high frequency refractive index, and metallization criterion have been evaluated; both the direct and indirect band gaps decreased in case of doped PVA films; and the results and the features are discussed.