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Transparent conductive Al doped ZnO thin films were deposited by ultrasonic spray technique. Conditions of preparation have been optimized to get good quality. A set of aluminum (Al) doped ZnO (between 0 and 5 wt%) thin films were grown on glass substrate at 350 ı C. Nanocrystalline films with a hexagonal wurtzite structure show a strong (002) preferred orientation. The maximum value of grain size G D 32.05 nm is attained of Al doped ZnO film with 3 wt%. All the films have low absorbance in the visible region, thus the films are transparent in the visible region; the band gap energy increased from 3.10 to 3.26 eV when Al concentration increased from 0 to 3 wt%. The electrical conductivity of the films increased from 7.5 to 15.2 ( cm) 1 . So the best results are achieved in Al doped ZnO film with 3 wt%.

In this work, we have prepared new materials of the nickel sulfide thin films by using the spray pyrolysis technique for promising co-catalyst to improve the photocatalytic performance or superconductivity. The effect of deposition temperature (523, 573 and 623 K) on structural, optical and electrical properties was investigated. The XRD diffraction shows that the prepared nickel sulfide at 523, 573 and 623 K having an orthorhombic, hexagonal and hexagonal structure, which were Ni3S2, Ni17S18 and NiS2, respectively. The minimum value of crystallite size (45,9 nm) was measured of deposited film at 573K. The thin films prepared at 523 and 573 K have an average transmittance is about 20 %. The prepared Ni1S2 thin film at T=623 K has the lowest calculated optical band gap and Urbach energy. The Ni1S2 thin film also has the best calculated of the refractive index and the extinction coefficient. The FTIR spectrums of the nickel sulfide have various bands such as Ni-S, C-H, O-H, N–H and C-S. The maximum electrical conductivity is 4,29x105 (Ω.cm)−1 was obtained at 573K of the Ni17S18. The nickel sulfide thin films sprayed at 573K have good structural, optical and electrical properties.

In this work, we prepared thin films of nickel sulfide by spray pyrolysis on substrates of the glass at temperature of 300°C. The solution used is a mixture of nickel acetate and thiourea as a source of nickel and sulfur respectively, acetic acid was used as a complexing agent, and then heated the resulting layers in an ordinary furnace at 300°C at different times of 1h, 2h and 3h to study the annealing time effect on the physical and chemical properties. The characterization methods used indicate remarkable changes in the structural, electrical, morphological and optical properties of NiS films under annealing time. The results obtained have shown that the prepared NiS films contain good crystallization, dense morphology, good stochiometric ratio and high conductivity, and these specifications make them a potential candidate as electrode material for application in super-capacitors.

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In this work, nickel oxide was fabricated on glass substrate at 450 °C by spray pyrolysis technique. The NiO layers were obtained with 0.05M molarity, which were deposited by various deposition rates 20, 40, 60 and 80 ml. The effects of deposition rate on the structural, electrical and optical properties were examined. All fabricated NiO thin films were observed a nanocrystalline a cubic structure with a strong (111) preferred orientation, it is only phase was observed in all deposited NiO. The film elaborated with 60 ml have a minimum value of crystallite size was 15.8 nm. All NiO thin films have an average transmittance is about 70 % in the visible region. The NiO thin films have a verity in the band gap energy from 3.34 to 3.51 eV because the effect of deposition, the minimum value was found at 80 ml, this condition have a lowest Urbach energy. The NiO thin films have an electrical resistivity was decreased from 0.625 to 0.152 (Ω.cm) with increasing the deposition rate from 20 to 80ml. The best results of NiO thin films are obtained in the deposition NiO films by 40 and 80 ml.

The effect of Zn doping on optical, structural and electrical properties of Ni1-xZnxO thin films has been successfully deposited on glass substrate by Spray Pyrolysis technique. The main objective of this research is to study the Ni1-xZnxO thin films to determine the optical gap energy by various methods and compare it with calculated values. The transmission spectra shows that the Ni1-xZnxO thin films have a good optical transparency in the visible region. The optical gap energy varied between 3.50 and 3.75 eV, which was determined by various methods and equations. they are explained in the curves of A, A2 , α, α2 (Ahυ) 2 and (αhυ) 2 as a function of the photon energy hυ. We observed that the suitable method to calculate the optical gap energy is (Ahυ) 2 versus hυ, but this method can't be related to the film thickness. The urbach energy of the Ni1-xZnxO thin films also was determined by the curves of LnA and Lnα as a function of photon energy hυ. We deduced that LnA versus hυ is also suitable to estimate the urbach energy. However, the Ni0.90Zn0.10O thin films have a few defects with minimum value of urbach energy. The Ni0.90Zn0.10O thin films have maximum value of optical gap energy. XRD patterns of the Ni1-xZnxO thin films indicate that films are polycrystalline with cubic structure. The electrical conductivity of our films is in the order of 9*10-3 (Ω.cm)-1 .

Nickel sulfide (NiS) thin film has been deposited on glass substrates by spray-pyrolysis at 325 ± 5 °C. The precursor aqueous solution was synthetized using hexahydrated nickel nitrates and thiourea. The structural, morphological, optical and electrical properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy and four probes electrical measurements. The XRD analysis confirmed the hexagonal structure of NiS thin film, which was found to crystalize along [010] direction with an average crystallites size of 10.5 nm. The lattice parameters are a = b = 3.420 Å and c = 5.300 Å in the space group P63/mmc. The optical properties of the films were investigated through the transmittance and the reflectance measurements. The results revealed that the material exhibits a direct optical band gap of 1.03 eV. The elementary composition analysis confirmed the presence of Ni and S with a stoichiometry ratio (Ni/S) of 1.05. The morphology analysis revealed a homogenous crack-free, compact appearance and a granular surface in all scanned areas. The average roughness of the surface was 6.48 nm. On the other hand, the film exhibits a high electrical conductivity ca. 1.10 × 105 S/cm at room temperature. The above results show that the prepared NiS in this study has a good crystallization, dense morphology, good stoichiometric ratio and high conductivity; therefore, it stands as a potential candidate for application in supercapacitors as an electrode material.