Nickel oxide (NiO) material had been reported as one interesting candidate for transparent conductive oxides (TCO) applications, given their specific properties. In this work, we have synthesized un-doped nickel oxide (NiO) thin films by using the spray pyrolysis method deposited on heated glass substrates at 500°C. The effect of the Nickel source on the optical and electrical properties of the prepared films had been reported. We have used two sources of nickel: nickel nitrate (Ni (NO3)2.6H2O) and nickel Chloride (NiCl2.6H2O). The characterization techniques such as UV–visible spectroscopy and the two-point probe technique were used to investigate the prepared NiO thin films. The optical analyses show that all the samples exhibit averaged optical transparency between 52% and 61% in the visible region. The evalueted optical gap- the energy of the NiO thin films between 3.59 and 3.84eV with the change of nickel source. Refractive index and extinction coefficient values were decreased with a variation of nickel source. From Electrical measurement, it was observed that the minimum resistivity of the NiO films are 0.106 Ω from films prepared with nickel nitrate source.

This study reports the chemical composition of seven sandstones (OH1-OH7) from Ouargla desert in south-east of Algeria, then the investigation of these samples to be used as precursor for the hydrothermal synthetesis of piezoelectric mater in thin films form. Fourier-transform infrared (FT-IR) spectra shows the characteristic vibration bond peaks for the seven samples documenting the presence of quartz and calcite. Moreover, chemical composition of Ouargla sandstones has been determined by energy dispersive X-ray (EDS) and X-ray diffraction (XRD) allowed mainly a composition avrage major of 86.86 % α-quartz (SiO2) and minor of 13.14 % calcite (CaCO3). The EDS analysis revealed the presence of solid solution in the crystal lattice of six samples of the sandstones with trace amounts of Fe, Al, Ag, Na, K. The aqua regia digestion method was used to extract silicon and calcium from the rock samples in to synthesis the thin films. From (FT-IR), (SEM-EDS) and (XRD) we show that synthesis thin films at different temperture are composed mainly of 90.66 % calcite (CaCO3)/9.33 % α-quartz (SiO2) and 69 % α-quartz (SiO2)/31% Sodium Chloride (NaCl). The crystallite sizes of the sandstones were calculated and estimated to be nanometric, in contrast the thin films are not nanometric.