Preparation of PbS compound and studying the effect of doping with barium on some of its physical properties

Abstract

Three Samples were prepared in the form of thin films of barium –doped Lead sulfide  , () on previously cleaned glass slides by chemical bath deposition (CBD) technique .

The surface structure of the prepared samples was studied using the Atomic Force Microscope (AFM) device . It was found that the surface structure of the samples is a nano – granular structure and the size of the granules decreases with the increase in the doping ratio .

The diffraction spectrum of X- rays on the samples ()was studied .The preferred direction of growth was according to the crystalline plane (200),and by analyzing the XRD spectrum of the prepared samples ,a decrease in the crystallization size was found with an increase in the dopant percentage by a decrease in the intensity of the dislocations.

The  feature was  studied for the prepared samples  at different temperatures for the first sample . The activation energy calculated and it was found to be equal  to 0.51 ev.  As for samples 2,3 no change in the feature   was observed with the change in temperature .

Using () Spectrometer , The absorption spectra of the prepared samples were studied within a wavelength range (200-1500)  , and the energy gap of samples was calculated , and an increase in the value of the energy gap was observed with the increase  in the percentage of doping .