Pure and Fe-doped zinc oxide nanocrystalline films were prepared
via a sol–gel method using -
C for 2 h.
The thin films were prepared and characterized by X-ray diffraction
(XRD), atomic force microscopy (AFM), field emission scanning
electron microscopy (FE-SEM) and UV- visible spectroscopy. The
XRD results showed that ZnO has hexagonal wurtzite structure and
the Fe ions were well incorporated into the ZnO structure. As the Fe
level increased from 2 wt% to 8 wt%, the crystallite size reduced in
comparison with the pure ZnO. The transmittance spectra were then
recorded at wavelengths ranging from 300 nm to 1000 nm. The
optical band gap energy of spin-coated films also decreased as Fe
doping concentration increased. In particular, their optical band gap
energies were 3.75, 3.6, 3.5, 3.45 and 3.3 eV doping concentration of
0%, 2%, 4%, 6% and 8% Fe, respectively. The performance of the
pure and doped ZnO thin films was examined for the photocatalytic
activity using organic dyes (methyl orange, methyl blue, methyl
violet). The samples ZnO with concentration of Fe showed increased
photocatalytic activity with an optimal maximum performance at
0.8 wt%.
Spin coating technique used to prepare ZnPc, CdS and ZnPc/CdS blend thin films, these films annealed at 423K for 1h, 2h and 3h. Optical behavior of these films were examined using UV-Vis. and PL. The absorption spectrum of ZnPc shows a decreasing in absorption with the increase of annealing time while CdS spectrum give a clearly absorption peak at~510 nm. Energy gap of ZnPc increases from 1.41 to 1.52 eV by increasing the annealing time. Eg of CdS decrease by increasing annealing time, from 2.3 eV to 2.2 eV. The intensities of the peaks obtained from PL spectra were strongly dependent on annealing time and confirmed the results obtained from UV-Vis. D.C. conductivity measurement showed that all the thin films have two differen
... Show MoreIn this work, Schiff base ligands L1: N, N-bis (2-hydroxy-1-naphthaldehyde) hydrazine, L2: N, N-bis (salicylidene) hydrazine, and L3:N –salicylidene- hydrazine were synthesized by condensation reaction. The prepared ligands were reacted with specific divalent metal ions such as (Mn2+, Fe2+, Ni2+) to prepare their complexes. The ligands and complexes were characterized by C.H.N, FT-IR, UV-Vis, solubility, melting point and magnetic susceptibility measurements. The results show that the ligands of complexes (Mn2+, Fe2+) have octahedral geometry while the ligands of complexes (Ni2+) have tetrahedral geometry.
In this work, functionally graded materials were synthesized by centrifugal technique at different
volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T
= 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites
and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina
(Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength
occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value was
at 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the fu
The use of piezocatalysis with photocatalysis in the degradation of organic pollutants has become an attractive research field due to the enhanced synergistic effect of the two processes. Herein, binary composites of AgBr decorated onto Br-doped g-C3N4 in different weight percentages (AgBr content was varied from 10 wt% to 40 wt%) have been built as heterojunction piezo-photo catalysts with a highly efficient performance. The 20 wt%AgBr/Br-g-C3N4 catalysts showed synergistically improved piezo-photo catalytic decomposition toward Methylene blue (MB) under visible-light and sonication exposure in a simple constructed split-plate airlift contactor, completing 99.7 % degradation of MB within 60 min. The heterogeneous junction established among
... Show MoreCopper Zinc Sulphide (Cu0.5Zn0.5S) alloy and thin films were fabricated in a vacuum. Nano crystallized (CZS) film with thick 450±20 nm was deposit at substrates glasses using thermal evaporation technique below ~ 2 × 10− 5 mbar vacuum to investigated the films structural, morphological and optical properties depended on annealing temperatures ( as-deposited, 423, 523 and 623) K for one hour. The influences annealed temperature on structurally besides morphologically characteristics on these films were investigated using XRD and AFM respectively. XRD confirms the formation a mixed hexagonal phase of CuS-ZnS in (102) direction with polycrystalline in nature having very fine crystallites size varying from (5.5-13.09) nm. AFM analys
... Show MorePlasma electrolytic oxidation and dip chemical coating as fabrication techniques are performed in ambient temperature and pressure, giving a competitive-edge in the commercial applicability. Thus, we proposed new compositions of flower-like hybrid materials, MgO-TiO2-HQ(8-hydroxyquinoline), MgOTiO2-HQ-APY(2-aminopyridine) and MgO-TiO2-HQ-APH(2-aminophenol), as photocatalysis with high corrosion resistance via a combination of plasma electrolytic oxidation and dip chemical coating in which 8-HQ, 2-APY, and 2-APH were used as the organic components. TiO2-HQ-APY and MgO-TiO2-HQ-APH exhibited improved simultaneous electrochemical and photocatalytic performance on photodecomposition of methylene blue (MB) in an aqueous solution in the presence o
... Show MoreCopper zinc tin sulfide selenide, Cu2 ZnSn(S1−x Se x)4 , absorbers are promising earth-abundant and environmentally benign materials for low-cost photovoltaic applications. This study investigates the structural and optical properties of Cu 2 ZnSn(S1−x Se x)4 nanostructured thin films prepared by pulsed laser deposition using melt-quenched targets with selenium compositions x = 0.0–1.0. X-ray diffraction revealed that films with low selenium content remained amorphous, whereas higher selenium incorporation promoted the formation of polycrystalline kesterite–stannite phases with preferred orientations along (112), (200), (220), and (312). The crystallite size increased from 12.3 to 17.9 nm as selenium reached x = 1.0, indicating enha
... Show MorePolymer blended electrolytes of various concentrations of undoped PAN/PMMA (80/20, 75/25, 70/30, 65/35 and 60/40 wt%) and doped with lithium salts (LiCl, Li2SO4H2O, LiNO3, Li2CO3) at 20% wt have been prepared by the solution casting method using dimethylformamide as a solvent. The electrical conductivity has been carried out using an LCR meter. The results showed that the highest ionic conductivity was 2.80x10-7 (Ω.cm)-1 and 1.05x10-1 (Ω.cm)-1 at 100 kHz frequency at room temperature for undoped (60% PAN + 40% PMMA) and (80% PAN + 20% PMMA) doped with 20%wt Li2CO3 composite blends, respect
... Show MorePolymer blended electrolytes of various concentrations of undoped PAN/PMMA (80/20, 75/25, 70/30, 65/35 and 60/40 wt%) and doped with lithium salts (LiCl, Li2SO4H2O, LiNO3, Li2CO3) at 20% wt have been prepared by the solution casting method using dimethylformamide as a solvent. The electrical conductivity has been carried out using an LCR meter. The results showed that the highest ionic conductivity was 2.80x10-7 (Ω.cm)-1 and 1.05x10-1 (Ω.cm)-1 at 100 kHz frequency at room temperature for undoped (60% PAN + 40% PMMA) and (80% PAN + 20% PMMA) doped with 20%wt Li2CO3 composite blends, respectively. It was found from the measurements of the A.C conductivity of undoped (PAN+PMMA) and doped with different lithium salts in the frequency
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