M. Taleblou, E. Borhani, B. Yarmand, A. Kolahi,
Volume 15, Issue 3 (9-2018)
Abstract
Thin films of SnS2 were prepared, as the absorber layer in solar cells, using an aqueous solution of SnCl4 and thiourea by spray pyrolysis technique. Effect of the Substrate temperature on the properties of these thin films was studied. Investigation via XRD showed the formation of polycrystalline SnS2 along (001) in all layers; there was no sign of other unwanted phases. With increasing of substrate temperature from 325 to 400 0C, the crystallinity of the sample was improved, after that, it deteriorated the crystallinity. Layers had granular morphology and Valley- Hills topography. UV-VIS spectra revealed that the transmittance of all layers was lower than 40% in the visible region and the band gap reduced from 2.8 to 2.55 eV with increment in temperature from 350 to 400 0C. Photoluminescence spectra of the prepared film, which was formed at 400 0C showed a dominant peak at 530 nm, caused recombination of excitons. The least electrical resistivity of the SnS2 thin film prepared at 400 0C in dark and light environment were 4.6 ×10 -3 Ωcm and 0.65×10 -3 Ωcm, respectively; which demonstrated 400 0C was the optimum temperature in point of optoelectrical properties in the SnS2 thin film.
S. M. Alduwaib, Muhannad M. Abd,
Volume 17, Issue 4 (12-2020)
Abstract
Graphene oxide thin layers, graphene oxide:silver nano-composite, graphene oxide:zinc oxide nano-composite and graphene oxide:zinc oxide/graphene oxide:silver bilayer were deposited by spray pyrolysis method. The synthesized thin layers were characterized using X-ray diffraction spectroscopy, field emission scanning electron microscope, energy dispersive x-ray spectroscopy and Raman spectroscopy. The optical properties and the band gap of the thin layers were also studied and calculated using the Tauc equation. Gram-negative bacterium of Escherichia coli was used to study the antibacterial properties of thin layers. The results showed that among the thin layers investigated, GO:ZnO/GO:Ag bilayer had the greatest effect on the inhibition of E. coli growth and was able to control the growth of bacterium after 2 hours.
