Investigation of key physical properties of new La@PbS filled Poly (vinyl and pyrrolidone) nanocomposite films for opto-electronics

Polymer blends incorporated with various nanoparticles are the key components for obtaining new and advanced physical properties for a wide area of applications. Herein, poly (vinyl and pyrrolidone) blend films containing different content of La@PbS nanoparticles are well prepared by following the casting procedure. La-doped PbS nanoparticles were facile synthesized via a chemical route at low temperatures. The structure of compositions was investigated through XRD, TEM, AFM, and FTIR. UV–visible spectroscopy shows that the absorption edge is redshifted to a higher wavelength and the absorbance increases with the La@PbS content. The direct and indirect transitions in the hybrid nanocomposites (HNCs) are reduced as the influence of filling percentage. Tauc’s model and quantum theory confirmed the presence of direct optical bandgap transitions in the HNC films. Urbach energy (E u ) and refractive index were also calculated. Through Wemple–Di Domenico’s (WDD) model of single-oscillator the optical susceptibilities and nonlinear refractive index were estimated. The dielectric constant and electrical conductivity of the HNC films are influenced not only by frequency but also by the La@PbS percentage. The dominant mechanism in all films is related to barrier hopping (CBH) and follows Jonscher’s power (JP) performance.