Band gap in PbS nanostructured thin films from near-infrared to visible range by in situ Ni-doping

The growth of nanocrystalline PbS films by chemical bath deposition (CBD) onto glass at a deposition temperature 80± 2°C is presented in the research. We report on the modification, optical nanostructures due to in situ Ni-doping. The morphological changes of the layers were analyzed using the Scanning Electron microscopy (SEM), and microscopy electronic transmission (TEM). X-ray diffraction (XRD) spectra displayed peaks at the angular positions 2θ = [26.00, 30.07, 43.10, 51.00, 53.48], indicating growth on the zinc blende face. The grain size (GS) determined by XRD of the undoped samples, was found ~36 nm, whereas with the doped sample is found ~32-5 nm, as calculated by employing Scherer’s formula. By TEM, the doped-PbS materials were found crystalline films in the range 3.5-5 nm. Optical absorption (OA), forbidden band gap energy (Eg) shift disclose a shift in the range 2.1-3.8 eV. Finally, Gibbs free energy calculation for the V[Ni2+] doping-PbS process was also established. Resumen