RESUMO
Chemical bath deposition (CBD) technique is utilized to grow lead-oxide (PbO) nanostructures (NSs) over PbO seed fabricated by physical vapor deposition (PVD) method on glass substrates. The effect of growth temperatures 50 and 70 °C on the surface topography, optical properties, and crystal structure of lead-oxide NSs has been studied. The investigated results suggested that the growth temperature has a huge and very considerable influence on the PbO NS, and the fabricated PbO NS has been indexed as the Pb3O4 polycrystalline tetragonal phase. The crystal size for PbO thin films grown at 50 °C was 85.688 nm and increased to 96.61 nm once the growth temperature reached 70 °C. The fabricated PbO nanofilms show a high rate of transmittance, which are â¼70 and 75% in the visible spectrum for the films deposited at 50 and 70 °C, respectively. The obtained Eg was in the range of 2.099-2.288 eV. Also, the linear attenuation coefficient values of gamma-rays for shielding the Cs-137 radioactive source increased at 50 °C. The transmission factor, mean free path, and half-value layer are reduced at a higher attenuation coefficient of PbO grown at 50 °C. This study evaluates the relationship between synthesized lead-oxide NSs and the radiation energy attenuation of gamma-rays. This study provided a suitable, novel, and flexible protective shield of clothes or an apron made of lead or lead oxide to protect against ionizing radiation that meets safety rules and protects medical workers from ionizing radiation.
RESUMO
Zinc sulfide (ZnS) thin films were prepared and synthesized by the chemical bath deposition (CBD) technique on microscopic glass substrates using stoichiometric amounts of the precursor materials (ZnSO4·7H2O, NH4OH, and CS(NH2)2). Structural, morphological, compositional, and optical characterization of the films were studied. The obtained thin films were found to exhibit polycrystalline possessions. The effect of annealing temperature on the crystallographic structure and optical bandgap of ZnS thin films were both examined. The grain size and unit cell volume were both found to be increased. In addition, the strain, dislocation density, and the number of crystallites were found to be decreased with annealing temperature at 300 °C. However, the annealed sample was perceived to have more Zn content than S. The optical characterization reveals that the transmittance was around 76% of the as-deposited thin film and had been decreased to ~50% with the increasing of the annealing temperature. At the same time, the bandgap energy of the as-deposited film was 3.98 eV and was found to be decreased to 3.93 eV after annealing.