Chromium oxide (Cr2O3) doped ZnO nanoparticles were prepared by pulsed laser deposition (PLD) technique at different concentration ratios (0, 3, 5, 7 and 9 wt %) of ZnO on glass substrate. The effects of ZnO dopant on the average crystallite size of the synthesized nanoparticles was examined By X-ray diffraction. The morphological features were detected using atomic force microscopy (AFM). The optical band gap value was observed to range between 2.78 to 2.50 eV by UV-Vis absorption spectroscopy, with longer wavelength shifted in comparison with that of the bulk Cr2O3 (~3eV). Gas sensitivity, response, and recovery times of the sensor in the presence of NH3 gas were studied and discussed. In the present work, we found that the sensitivity was increased upon increasing the concentration ratio from 3 to 5%wt of ZnO, whereas it was decreased again over that value. Also, we found that the sensitivity was increased when increasing operating temperature, while the response time was decreased. The optimum concentrations ratio for NH3 gas sensitivity at 5%wt ZnO revealed sensitivity of 66.67% and response time of 14s at operating temperature of 300oC and 700mJ PLD energy.
Thin films of BhSe3 have being deposited on glass substrates of
about 80 - 172 ± 14 nm thickness from an aqueous solution bath at temperature 293 K for period 0.5 to 6.0 hours using alchemical bath deposition method .
The films are characterized by X-ray diffraction, X-ray
florescent techniques and optical transmittance spectra measurements in the rang 350 - 400 nm at 293 K. And shows that as deposited films are amorphous and a transition to polycrystalline state has taken place after annealing them at 373 K, for 30 minutes, But they will be dan1aged
... Show MoreTin Selenide (SnSe) Nano crystalline thin films of thickness 400±20 nm were deposited on glass substrate by thermal evaporation technique at R.T under a vacuum of ∼ 2 × 10− 5 mbar to study the effect of annealing temperatures (as-deposited, 100, 150 and 200) °C on its structural, surface morphology and optical properties. The films structure was characterized using X-ray diffraction (XRD) which showed that all the films have polycrystalline in nature and orthorhombic structure, with the preferred orientation along the (111) plane. These films was synthesized of very fine crystallites size of (14.8-24.5) nm, the effect of annealing temperatures on the cell parameters, crystallite size and dislocation density were observed.
... Show MoreNanostructural cupric oxide (CuO) films were prepared on Si and glass substrate by pulsed laser deposition technique (PLD) using laser Nd:YAG, using different laser pulses energies from 200 to 600 mJ. The X-ray diffraction pattern (XRD) of the films showed a polycrystalline structure with a monoclinic symmetry and preferred orientation toward (111) plane with nano structure. The crystallite size was increasing with increasing of laser pulse energy. Optical properties was characterized by using UV–vis spectrometer in the wave lengthrange (200-1100) nm at room temperature. The results showed that the transmission spectrum decreases with the laser pulses energy increase. Sensitivity of NO2 gas at different operating temperatures, (50°C,
... Show MoreMetal nanoparticles (NPs) of silver (Ag), copper (Cu), zinc oxide (ZnO), cadmium oxide (CdO) and tin (Sn) were synthesized by laser ablation of a solid target in de-ionized water (DI). X-ray diffraction patterns showed the formation of AgO, Ag, Cu, ZnO, CdO, and Sn NPs. Absorbance spectrum of the produced nanoparticles was measured by UV-Vis spectrophotometer which showed that Ag and CdO NPs shifted to the short wavelength (blue shift), indicating the formation of NPs with smaller sizes, whereas CuO showed the formation two peaks. ZnO and Sn NPs shifted to the long wavelength (red shift) which indicates the formation NPs with larger size. Zeta potential results proved that ZnO nanoparticles were more stable (-26.53mV) than the othe
... Show Morein this paper, the current work was devoted to the manufacture of TiO2 nanoparticles doped with manganese, synthesis by the sol-gel technique using a dip-conting device, for their hydrophilic properties and photocatalytic activity, and the products were characterized by X-ray diffraction, scanning electron microscopy, and Uv-Visible absorption, and the results XRD showed an phase Anatase , and the results of the SEM Explained the shape of the morphology of the samples after the doping process compared with pure TiO2, and the results of a shift in light absorption from ultraviolet rays to visible light were evident. The results showed that the thin films have a high wettability under visible rays
... Show MoreIn this paper Zener diode was designed by mixing three mixing ratios of Ag2O(1-x)ZnO(x), where x is 0.5, 0.3, and 0.1, that are deposited on a p-type porous silicon using laser induced plasma technique at room temperature (RT). The results of the Zener diode showed a decrease in knee and Zener voltage when the mixing ratio of Ag2O(1-x)ZnO(x) structure was increased. Nanofilms of 200nm thickness were prepared from pure ZnO and Ag2O as well as Ag2O(1-x)ZnO(x) with three maxing ratios and deposited on glass slides at RT to analyze the structure and optical properties. The structures of Ag2O and Ag2O
This work investigates the structural, optical, and surface properties of ZnO thin films prepared by sol-gel method. The effect on waveguide sensor was examined at different irradiation durations of alpha particles. The X-ray diffraction (XRD) measurements revealed that the crystalline phase of ZnO thin films does not change after irradiation and showed a hexagonal structure of wurtzite type with an orientation toward (002). Moreover, ZnO thin films absorbance was increased with increasing irradiation time, whereas the transmittance was decreased. Additionally, increasing the irradiation time of alpha particles caused an increase in the extinction coefficient and the imaginary part, while the optical energy gap of the ZnO samples w
... Show MoreIn this paper, the effect of films thickness on the structural and optical properties of gold (Au) thin films prepared by the DC sputtering method was studied. At three different deposition times, three samples of gold thin films of three different thicknesses (200,400, and 600 nm) were prepared. X-ray diffraction patterns, scanning electron microscopy (SEM), and atomic force microscopy (AFM) images, as well as optical spectroscopy, were used to characterize thin films. The crystalline structure of gold thin films was determined by the XRD pattern which showed to be cubic phase and polycrystalline in nature. The preferred orientation was (111) at 2Ѳ equal 37.4. The effect of deposition time on the morphology of the deposited films was v
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