In this study, an easy, low-cost, green, and environmentally
friendlier reagents have been used to prepare CdS QDs, in chemical
reaction method by mixed different ratio of CdO and sulfur in
paraffin liquid as solvent and oleic acid as the reacting media in
different concentration to get the optimum condition of the reaction
to formation CdS QDs. The results give an indication that the
behavior is at small concentration of 4ml of the oleic acid is best
concentration which give CdS QDs of small about to 9.23 nm with
nano fiber configuration.
In this research, We study the effect of irradiation by gamma rays from (Cs137) source for the period time (21) days on optical propertices such as absorption coeffeicient (ï¡)and energy gap (Eg) for copper oxides thin films (CuO) prepared by the chemical spray pyrolysis and deposited on glass substrates at (350oC) for two different thicknesses ( 1000Ã…and 3000Ã…) .
Thin films of (CuO)x(ZnO)1-x composite were prepared by pulsed laser deposition technique and x ratio of 0≤ x ≤ 0.8 on clean corning glass substrate at room temperatures (RT) and annealed at 373 and 473K. The X-ray diffraction (XRD) analysis indicated that all prepared films have polycrystalline nature and the phase change from ZnO hexagonal wurtzite to CuO monoclinic structure with increasing x ratio. The deposited films were optically characterized by UV-VIS spectroscopy. The optical measurements showed that (CuO)x(ZnO)1-x films have direct energy gap. The energy band gaps of prepared thin films
Thin films of zinc selenide ZnSe have been prepared by using thermal evaporation method in vacuum with different thickness (1000 – 4000) Ao and a deposited on glass substrate and studying some electrical properties including the determination of A.C conductivity and real, imaginary parts of dielectric constant and tangent of loss angle. The result shows that increasing value of A.C conductivity with increasing thickness and temperature, and increasing capacitance value with increasing the temperature and decrease with increasing frequency . Real and imaginary parts of dielectric constant and tangent of loss angle decrease with increasing frequency
In this work, Titanium oxide thin films doped with different concentration of CuO (0,5,10, 15,20) %wt were prepared by pulse laser deposition(PLD) technique on glass substrates at room temperature with constant deposition parameter such as : pulse (Nd:YAG), laser with λ=1064 nm, constant energy 800 mJ , repetition rate 6 Hz and No. of pulse (500). The structure , optical and electrical properties were studied . The results of X-ray diffraction( XRD) confirmed that the film grown by this technique have good crystalline tetragonal mixed anatase and rutile phase structure, The preferred orientation was along (110) direction for Rutile phase. The optical properties of the films were studied by UV-VIS spectrum in the range of (360-1100)
... Show MoreQuantum dots (QDs) of cadmium sulfide (CdS) was prepared by chemical
reaction method with different potential of hydrogen (pH) values. The
morphological and optical measurements of cadmium sulfide QDs were considered
by atomic force microscopy (AFM), ultraviolet-visible (UV-VIS.) and
photoluminescence (PL) spectrometer respectively. The energy gap (Eg) was
calculated from photoluminescence spectra were found to be about 2.7, 2.6 and 2.5
eV at pH values 8, 10 and 12 respectively for CdS QDs. The decreasing of energy
gaps is rises from the effect the pH solution increases, which in turn leads to the
shifted of the PL spectrum toward red shifted, which creates the energy bands at
surface states are shallow bands.
In the present study, the structural properties which included the X-rays diffraction, and DSC, the mechanical properties, which include tensile test, threepoint bending test (Bending Test), hardness test and thermal conductivity of the polymers reinforced with calcite (PVC/CaCO3) at different temperature (25-40-80-
120-160-200-220) °C. The research results showed that the XC degree of X-ray diffraction decreased at high temperatures (220 ˚C), while the inter-polymerized polymer (PVC / CaCO3) increased at high temperatures. The DSC test results showed that the degree of crystallinity (XC) decreases at high temperatures (220 ˚C). The mechanical test results, their values were found to decrease at (