In-situ synthesis of PbS nanocomposites films in PEOX-PVA: Interaction effect of parent polymer matrix on structural and optical properties

Abstract

This paper reports the in-situ synthesis of PbS nanoparticle films grown in the PEOX-PVA polymer matrix. The films have been prepared for various concentrations of PbS nanoparticles developed in blend polymer PEOX-PVA along with its parent polymers PEOX and PVA. The effect of polymer matrix on its structural properties has been studied using Rietveld analysis of x-ray diffraction data to determine the following parameters, i.e., crystal structure, space group, lattice parameter, and crystallite size. The chemical bonding and interaction effect of the parent polymer matrix with PbS nanoparticles have been analysed using FTIR and thermal gravimetry. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) have been used to observe the overall morphology of the nanocomposites. The variation in the bandgap of PbS nanocomposite films has been determined from 3.6 to 1.25 eV with varying concentrations of PbS (0.01 M–0.1 M) in all three polymer matrices. The refractive index of PbS nanocomposites films deduced at λ = 650 nm to be 1.4333 to 1.5612, which is much lower than the bulk value of 4.2. It is inferred from the present study that the interaction of polymer matrices with the PbS does not lead to mere addition. Detailed results are analysed considering the quantum confinement effect.