Band Gap Engineering of Binary and Cobalt-Doped PbS Thin Films Integrated by SILAR Method for Optoelectronic Potentials

Thin films of PbS, both undoped and cobalt-doped (Co-PbS), were produced on glass substrates using the straightforward and controllable approach of sequential ionic layer adsorption and reaction (SILAR). The reactive substances employed to deposit the PbS thin films were lead nitrate (Pb(NO ) ), cobalt nitrate (Co(NO₃)₂(H₂O)₆), sodium thiosulphate (Na S O ) and H O for different dipping concentrations of lead and cobalt. The films were adherent to the substrate and were compact, and crack-free with a shiny silver color. The films were structurally characterized by XRD and were found well crystallized according to the face-centered cubic formation. The films were optically characterized by the UV-Vis. spectrophotometer and absorption were found stronger in the UV and UV-Vis. region and then diminishes. Band gaps were determined to be between 1.8 eV and 2.2 eV, making them significant materials with the option of band gap engineering according to the desire by manipulating the compositions.