Publications by authors named "Metwally Madkour"

In this contribution, the performance of powdered titanium dioxide (TiO)-based photocatalysts was evaluated in a pilot photocatalytic plant for the degradation of different dyes, with an investigated volume of 1 L and solar simulated light as irradiation source. Five different samples, synthesized in our laboratories, were tested in the pilot plant, each consisting of TiO nanoparticles (NPs) coupled with a different material (persistent luminescent material and semiconductor material) and treated in different thermal conditions. All synthesized samples have been subjected to X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller analysis (BET), and transmission electron microscopy (TEM) characterization, to shed light on the influence of introducing other materials on titania characteristics.

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Binary metal oxide/ternary metal sulphide based nanoheterostructures, such as CuO/CuSnS, were prepared via a modified hydrothermal route. The prepared nanoheterostructures were characterized using scanning electron microscopy, x-ray powder diffractometer, XPS, ultraviolet-visible spectroscopy, isoelectric point, and Brunauer-Emmett-Teller techniques. The XPS results revealed the successful incorporation of Cu/Cu with different ratios.

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Mo/Tc generators play a significant role in supplying Tc for diagnostic interventions in nuclear medicine. However, the applicability of using low specific activity (LSA) Mo asks for sorbents with high sorption capacity. Herein, this study aims to evaluate the sorption behavior of LSA Mo towards several CeO nano-sorbents developed in our laboratory.

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In this paper, we studied the electrochemical capacitive performance of thermally evaporated copper iodide thin film doped with different quantities of Al (3, 5, 7, and 9 mol%). The morphological structure, crystalline nature, and surface composition of the deposited films with different dopant levels were confirmed using X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FE-SEM). The electrochemical performance was evaluated based on cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) measurements, and electrochemical impedance spectroscopy (EIS) in a NaSO electrolyte.

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Removal of heavy metal pollutants from water is a challenge to water security and the environment. Therefore, in this work, multinary chalcogenide based nanoheterostructures such as ZnS/SnInS nanoheterostructure with different loading amounts were prepared. The prepared nanoheterostructures were utilized as photocatalysts for chromium (Cr(vi)) photoreduction.

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Chitosan/magnesia hybrid films (CS-Mg) have been prepared via sol-gel process and employed as heterogeneous catalysts. An in situ generation of a magnesia network in the chitosan matrix was performed through hydrolysis/condensation reactions of magnesium ethoxide. The synthesized hybrid films were characterized using various analytical techniques, such as X-ray photo-electron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM).

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A series of metal complexes were prepared from separate reactions of lanthanide nitrate salts (La(iii), Ce(iii), Sm(iii), Gd(iii) and Ho(iii)) with 4-methylbenzoylhydrazide. The structures of the complexes were confirmed by analytical studies, spectral measurements and thermal studies. Complexes were formed with different stoichiometries of 1 : 2 and 1 : 3 (M : L).

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The use of carbon black-FeO magnetic nanocomposite (CB-FeO) as a probe for surface-enhanced laser desorption ionization mass spectrometry (SELDI-MS) with a high extraction efficiency and sensitive detection is described. The magnetic nanocomposite was synthesized and fully characterized using X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, Ultraviolet-Visible spectroscopy, transmission electron microscopy and nitrogen sorption. The feasibility of the SELDI probe to extract and detect three classes of drugs (labetalol, metoprolol, doxepin, desipramine, triprolidine and methapyrilene) spiked in wine is demonstrated.

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Colloidal synthesis of nanoparticles using polymeric stabilizers as a template of a structure directing agent provided a plethora of opportunities in fabricating nanoparticles (NPs) with controlled size, shape, composition and structural characteristics. To understand the complete potency of polymeric stabilizers during the synthesis of nanoparticles, the relationship between polymer characteristics such as structure, molecular weight and concentration and nanoparticles characteristics is discussed in depth. This review portrays the use of polymers to attain nanostructured materials via covalent and non-covalent approaches.

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We explored the applicability of different metal oxide nanoparticles (NPs; ZnO, TiO, FeO, and CeO) for the optical imaging and mass spectrometric determination of small drug molecules in latent fingerprints (LFPs). Optical imaging was achieved using a dry method-simply dusting the LFPs with a minute amount of NP powder-and still images were captured using a digital microscope and a smartphone camera. Mass spectrometric determination was performed using the NPs as substrates for surface-assisted laser desorption ionization/mass spectrometry (SALDI-MS), which enabled the detection of small drug molecules with high signal intensities.

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SALDI-MS analysis of pharmaceutical drug molecules (amitriptyline, imipramine and promazine) using carbon-based substrates, namely, activated charcoal (AC), carbon nanotubes (CNTs), carbon black (CB), graphene (rGO), graphene oxide (GO) and graphite, was explored and compared with the conventional organic matrix of MALDI. CB exhibited superior performance with respect to the other substrates in terms of detection sensitivity. Despite the effectiveness of CB to detect all drug molecules, it demonstrated a number of background signals, which may be an issue for the analysis of other molecules in the future.

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Herein, a simple approach based on tailoring the surface charge of nanoparticles, NPs, during the preparation to boost the electrostatic attraction between NPs and the organic pollutant was investigated. In this study, chargeable titania nanoparticles (TiΟ NPs) were synthesized via a hydrothermal route under different pH conditions (pH = 1.6, 7.

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Herein, we report the synthesis of chromium oxide nanoparticles, α -CrO NPs, followed by full characterization via XRD, SEM, XPS, and N sorptiometry. The synthesized nanoparticles were tested as catalysts toward the oxidation of CO. The impact of calcination temperature on the catalytic activity was also investigated.

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Zinc oxide (ZnO) nanostructures of uniform shapes and sizes (spherical, needle-like, and acicular) were directly synthesized using a relatively precursor-insensitive water-in-n-heptane microemulsion system stabilized by a mixture of cationic and non-ionic surfactants. With this colloidal system, the synthesized ZnO possesses the highest reported surface area (76 m(2) g(-1)) among the published reports utilizing other microemulsion systems. Such precursor insensitivity allowed studying the effect of Zn precursor:precipitating agent molar ratio (as high as 1:8) on the particle size, specific surface area, porosity, and morphology of the synthesized nanoparticles.

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Although TiO2 is one of the most efficient photocatalysts, with the highest stability and the lowest cost, there are drawbacks that hinder its practical applications like its wide band gap and high recombination rate of the charge carriers. Consequently, many efforts were directed toward enhancing the photocatalytic activity of TiO2 and extending its response to the visible region. To head off these attempts, modification of TiO2 with noble metal nanoparticles (NMNPs) received considerable attention due to their role in accelerating the transfer of photoexcited electrons from TiO2 and also due to the surface plasmon resonance which induces the photocatalytic activity of TiO2 under visible light irradiation.

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The structure of solubilized water in water-in-n-heptane aggregates stabilized by mixtures of single- and double-tail quaternary ammonium surfactants, namely didodecyldimethylammonium chloride/dodecyltrimethylammonium chloride (DDAC/DTAC) or didodecyldimethylammonium bromide/dodecyltrimethylammonium bromide (DDAB/DTAB) was studied by two noninvasive techniques, (1)H NMR and FT-IR. In the former, the chemical shift data, δ(obs), were used to calculate the so-called deuterium/protium fractionation factor, φ(M), of the aggregate-solubilized water and were found to be unity. In the FT-IR study, upon increasing water/surfactant molar ratio, W, the frequency, ν(OD), of the HOD species decreases, while its full width at half height and its area increase.

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