Fabrication of heterostructure solar cell using the optimized Sn incorporated PbS films via atomized nebulizer spray pyrolysis

Thin films of PbS doped with tin (2 ≤ Sn ≤ 8 wt.%) were deposited on glass substrates by cost- effective nebulizer spray method. X-ray diffraction studies confirm the polycrystalline nature with a face centered cubic structure along with the orientation of (200) plane. SEM/AFM studies reveal that the nano-sized spherical and granular shaped grains roofed the whole film surface and the grain shapes were changed with the change in Sn doping percentage. Bandgap was found to decrease from 1.98 eV to 1.66 eV with an increase in the doping concentration from 2 to 6 wt%. Hall Effect measurement confirmed p-type conducting nature for all the doped PbS films. The resistivity and carrier concentration values are found to be about 0.32 × 103 Ωcm and 6.78 × 1013 cm−3, respectively, for the optimized PbS:Sn film (6 wt%). The response of the heterostructured (FTO/n-CdS/p-PbS:Sn/Ag) solar cell with the optimal Sn doping (6 wt% Sn) was studied under dark and illuminated conditions.