Copper Sulfide (CuS) thin films were deposited onto a glass substrate using the Chemical Bath Deposition (CBD) technique. The chemical bath Precursors were made up of CuSO4, SC(NH2)2, and C4H6O6. Different parameters have been considered to specify the optimum conditions for fabricating CuS thin films, such as solution temperature, deposition time, pH level, and different precursor concentrations. It has been found that the optimum deposition time is 20 min at temperature 80 °C and pH = 11. The optimum precursor concentrations were 0.15 M, 0.2 M, and 0.1 M of CuSO4, SC(NH2)2, and C4H6O6, respectively. The structural properties of the thin film were studied using X-ray diffraction (XRD), and a single peak was observed for the thin film made at optimum conditions, while all other cases were amorphous. It is obvious from the optical characterization that the transmission spectra show a red-shift for the cases of increasing deposition time, bath temperature, C4H6O6 concentration, and pH. For the case of increasing CuSO4, blue shifts in the transmission spectra were observed. The energy band gap, resistivity, and activation energy of CuS thin films under optimum conditions are 2.35 eV, 0.7 Ω·cm, and 0.0152 eV, respectively.

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.

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Nanostructured cadmium oxide (CdO) thin films were deposited onto glass substrates using the chemical bath deposition (CBD) technique. Different deposition parameters such as deposition time, bath temperature, pH, and CdSO4 concentration have been considered to specify the optimum conditions to obtain uniform and well-adherent thin films. The thin films prepared under these optimum conditions were annealed for different times (20, 40, and 60 min) at 300 °C, where no previous studies had been done to study the effect of annealing time. The XRD analysis showed that the as-deposited film is Cd(OH)2 with a hexagonal phase. While all the annealed films are CdO with a cubic phase. The crystallite size increases with the annealing time. However, the strain, dislocation density, and the number of crystallites were found to be decreased with annealing time. SEM images of annealed films showed a spherical nanoparticle with an average of particle size 80–46 nm. EDX analysis revealed that the ratio of cadmium to oxygen increases with increasing the annealing time to 40 min. The optical characterization shows that the transmittance is in the range of 63–73% and the energy gap is in the range of 2.61–2.56 eV. It has been found that the transmittance increased and the energy gap decreased with the annealing time. The prepared CdO films can be used in photodegradation applications to remove pollutants from water.

Recently, the efficient preparation techniques of zinc sulfide (ZnS) nanostructured films have drawn great attention due to their potential applications in optoelectronics. In this study, the low-cost and high-yield chemical bath deposition (CBD) technique was used to deposit ZnS nanostructured thin films. The effect of various deposition parameters such as time, pH, precursor concentration, and temperature on the morphology and energy bandgap (Eg) of the prepared thin films were investigated. The characterization of the prepared thin films revealed the formation of polycrystalline ZnS with Narcissus-like nanostructures. Moreover, the optical characterization showed inverse proportionality between both the transmission and Eg of the nanostructured thin films and the variation of the deposition parameters. A range of different Eg values between 3.92 eV with 20% transmission and 4.06 eV with 80% transmission was obtained. Tuning the Eg values and transmission of the prepared nanostructured films by manipulating the deposition parameters of such an efficient technique could lead to applications in optoelectronics such as solar cells and detectors.