Abstract
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.
•First time investigation on Sn incorporation of PbS structure by nebulizer spray pyrolysis.•Reported the reduction phenomena of band gap with respect to doping influence for enhancing cell efficiency.•Produced PbS:Sn film with low resistivity (0.32 × 103Ωcm) and high carrier concentration (6.78 × 1013 cm−3).•Fabricated FTO/n-CdS/p-PbS:Sn/Ag heterostructure exposed reasonable cell efficiency of about 0.73%.•The 6 wt% of Sn was found as most suitable doping level for the host PbS structure.