Polyaniline (PANI) polymer was successfully prepared by the chemical oxidation method at 0 oC. Polyaniline-nano grapheme (GN) powder nanocomposites were prepared by the addition of GN with different weight ratios (0.1, 1, 5, and 10 g wt. %) during the polymerization of PANI. It was found that the polymerization reaction of poly-aniline was exothermic. The effect of adding nano-graphene powder during polymerization process on the time and temperature of the reaction was studied. The resulting polymer was diagnosed using several methods, including Fourier transform infrared spectroscopy (FT-IR) and UV-VIS spectrophotometry. The results of FTIR demonstrated a shift to higher wave numbers in the peaks of nanocomposites, due to PANI peaks, in addition to the matching between the groups of active sites of the polymer with its chemical composition. The results of the optical properties showed a decrease in the energy gap of the nanocomposite compared with that of the pure PANI sample. The morphology of the samples was studied using Scanning Electron Microscope (SEM). The increase in the concentration of GN led to a change in the surface morphology of the composites. The results predict that the PANI/GN nano-composites can be used in many applications, such as those of sensors.
Zinc Oxide transparent thin films (ZnO) with different thickness from (220 to 420)nm
±15nm were prepared by thermal evaporation technique onto glass substrates at 200 with
the deposition rate of (10 2) nm sec
-1
, X-ray diffraction patterns confirm the proper phase
formation of the material. The investigation of (XRD) indicates that the (ZnO) film is
polycrystalline type of Hexagonal and the preferred orientation along (002) plane. The Optical
properties of ZnO were determined through the optical transmission method using ultraviolet-visible spectrophotometer with wavelength (300 – 1100) nm. The optical band gap values of
ZnO thin films were slightly increased from (2.9 - 3.1) eV as the film thickn
Structural and optical properties of CdO and CdO0.99Cu0.01 thin
films were prepared in this work. Cadmium Oxide (CdO) and
CdO0.99Cu0.01semiconducting films are deposited on glass substrates
by using pulsed laser deposition method (PLD) using SHG with Qswitched
Nd:YAG pulsed laser operation at 1064nm in 6x10-2 mbar
vacuum condition and frequency 6 Hz. CdO and CdO0.99Cu0.01 thin
films annealed at 550 C̊ for 12 min. The crystalline structure was
studied by X-ray diffraction (XRD) method and atomic force
microscope (AFM). It shows that the films are polycrystalline.
Optical properties of thin films were analyzed. The direct band gap
energy of CdO and CdO0.99Cu0.01 thin films were determined from
(αhυ)1/2 v
X-ray diffraction pattern reveled the tetragonal crystal system of SnO2 Thin films of SnO2 were prepared on glass substrates using Spray Pyrolysis Technique. The absorption and transmition spectra were recorded in the rang of 300-900nm, the spectral dependences of absorption coefficient were calculated from transmission spectra. The direct and allowed optical energy gap has been evaluated from plots of (αhυ)² vs. (hυ) . The energy gap was found to be 2.4-2.6eV. The optical constant such as extinction coefficient( k ) and absorption coefficient ( α) have been evaluated.
The influence of sintering and annealing temperatures on the structural, surface morphology, and optical properties of Ag2Cu2O4 thin films which deposited on glass substrates by pulsed laser deposition method have been studied. Ag2Cu2O4 powders have polycrystalline structure, and the Ag2Cu2O4 phase was appear as low intensity peak at 35.57o which correspond the reflection from (110) plane. Scan electron microscopy images of Ag2Cu2O4 powder has been showed agglomerate of oxide particles with platelets shape. The structure of thin films has been improved with annealing temperature. Atomic Force micrographs of Ag2Cu2O4 films showed uniform, homogenous films and the shape of grains was almost spherical and larger grain size of 97.85 nm has o
... Show MoreIn this work, the effect of Zn dopant on structural and optical properties of cadmium oxides, CdO, thin film were studied prepared by pulse laser deposition on glass substrate then annealed at 250 ᵒC in air. All films were examined by X-ray diffraction and UV- visible spectrometer. The XRD analysis shows appearance of new phase identical with hexagonal ZnO additional with cubic phase at high Zn content, which effected on the optical properties. The optical energy gap increase from 2.45 eV to 2.70 eV with increasing Zn content from 0 to 40 %.
Undoped and Co-doped zinc oxide (CZO) thin films have been prepared by spray pyrolysis technique using solution of zinc acetate and cobalt chloride. The effect of Co dopants on structural and optical properties has been investigated. The films were found to exhibit maximum transmittance (~90%) and low absorbance. The structural properties of the deposited films were examined by x-ray diffraction (XRD). These films, deposited on glass substrates at (400? C), have a polycrystalline texture with a wurtzite hexagonal structure, and the grain size was decreased with increasing Co concentration, and no change was observed in lattice constants while the optical band gap decreased from (3.18-3.02) eV for direct allowed transition. Other parameters
... Show MoreAbstract : Tin oxide SnO2 films were prepared by atmospheric chemical vapor deposition (APCVD) technique. Our study focus on prepare SnO2 films by using capillary tube as deposition nozzle and the effect of these tubes on the structural properties and optical properties of the prepared samples. X-ray diffraction (XRD) was employed to find the crystallite size. (XRD) studies show that the structure of a thin films changes from polycrystalline to amorphous by increasing the number of capillary tubes used in sample preparation. Maximum transmission can be measured is (95%) at three capillary tube. (AFM) where use to analyze the morphology of the tin oxides surface. Roughness and average grain size for different number of capillary tubes have b
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