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CdSx thin films (x = 1.0, 0.8, 0.6, 0.4, 0.2) were prepared by the sol–gel spin coating method. The grazing incidence diffraction and Raman spectroscopy techniques were applied to explore the phases formed and microstructure of the produced thin films. The chemical composition of the formed thin films was investigated using X-ray photoelectron spectroscopy (XPS) measurements. Raman spectra revealed the presence of minor CdO phase in films with x = 0.4 and 0.2. Optical parameters could be modified by changing the ratio (x). The influence of sulfur deficiency on the optical properties was explored using photoluminescence and UV–Vis–NIR spectrophotometer techniques. Relative to CdS film, the reflectivity and the refractive index of S-deficient films, except for x = 0.8, decreased in the range 300–400 nm, after that increased a little in 400–530 nm, then increased in 530–1400 nm. The optical bandgap changed from 2.49 eV for CdS to 2.47, 2.58, 2.56, and 2.46 eV for x = 0.8, 0.6, 0.4, and 0.2, respectively. The optical parameters of the films were obtained using Wemple and DiDomenico model. In the whole wavelength range, CdS0.8 attained the highest optical conductivity values. All films emitted green and blue colors but with different intensity dependent on the parameter (x). [ABSTRACT FROM AUTHOR]

Zn and Mn co-doped nano-NiFe2O4 (NFO) system was prepared by alloying NFO with ZnMn2O4 (ZMO) samples. The possibility of forming NFO single phase was examined using X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) techniques. The effects of co-doping on the crystallite size, cell parameter and cation distribution of NFO were investigated. All samples were found to be non-stoichiometric with Ni2+ excess residing at the octahedral sites. The FTIR tetrahedral band was shifted to lower wavenumbers as the amount of Zn and Mn doping increased in NFO matrix. All ions oxidation states were detected using the X-ray photoelectron spectroscopy technique. The effects of alloying between NFO and ZMO on the diffused absorbance, reflectance spectra, extinction coefficient, refractive index, dielectric constant, conductivity and direct optical bandgap energy were examined using diffused reflectance technique. The nanocomposite samples emitted UV, violet, blue and green colors with photoluminescence (PL) intensity dependent on the amount of ZMO doping in the matrix. [ABSTRACT FROM AUTHOR]