Influence of gamma irradiation on the properties of PbS thin films

γ-Ray-Induced Photocatalytic Activity of Bi-Doped PbS toward Organic Dye Removal under Sunlight

“…However, the band gap has decreased (2.2 eV for pristine) after irradiation and indicates an absorption edge shift (Figure ). Band gap reduction is because of displacement of atoms from their sites due to the annealing effect of γ-irradiation . Similar reductions in optical bandgap energy have been reported by Sarker et al as a result of high-dose gamma irradiation’s ability to reduce defects and disorderliness at grain boundaries …”

“…Irradiated PbS:Bi has lower dislocation, microstrain, and stacking fault than pristine PbS, reflecting an increase in crystallite size, and a reduction in crystal lattice defects. Ali et al examined a similar increase in the crystallite size when they used high-dosage gamma irradiation on PbS grown employing the SILAR technique . All of these results support the improvement in crystallinity caused by gamma irradiation.…”

“…The allowed 3 P 1 → 1 S 0 transition of the Bi 3+ ion has been attributed to a broad blue emission band with its center at 446 nm (2.78 eV). Because of the quenching effect, which reduces electron–hole recombination, we notice a drop in peak intensity in doped PbS samples . This is the result of the postdoping disturbance of the density state at the VB edge .…”

“…All products were exposed to the same extremely high dose of radiation (90 kGy). This dosage was decided after reviewing the relevant literature. , …”

“…In recent years, high-energy γ-irradiation’s impact on nanomaterials has been the subject of extensive study. , These high-energy gamma rays can penetrate the crystal lattice and cause changes to the material’s physical properties. − Depending on the energy of the γ-rays, they interact with matter in one of the three ways: either through Compton scattering, the photoelectric effect, or pair creation. High-energy gamma irradiation causes ionization in the material, which in turn causes defects in the form of an alteration in atoms or ions energy levels that make up the material.…”