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result(s) for
"Abdel-wahab, Mohamed Sh"
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A comparison between adsorption and photocatalytic degradation for the management of sulfamethoxazole in water
by
Elkomy, Ahmed Salah
,
Shehata, Nabila
,
Sh. Abdel-wahab, Mohamed
in
639/638
,
704/172
,
Adsorption
2025
Sulfamethoxazole (SMX) is one of the majority of vital antibiotic medications and is widely employed for the treatment of bacterial infections. This pharmaceutical residue has been detected in surface water and sewage wastewater treatment plants (WWTP). Moreover, it has negative impacts on humans and ecosystems. The main aim of this work is to remediate water from SMX using two different water treatment techniques i.e. adsorption and photocatalytic degradation by using silver phosphate (Ag
3
PO
4
). The materials were characterized using structural (e.g. elemental dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD), and morphological (Brunauer–Emmett–Teller (BET), and scanning electron microscopy (SEM)) analytical methods. The percentage of elimination of SMX at optimum solution pH, adsorbent dose, initial drug concentration and equilibrium time, was 95.15% by adsorption which corresponds to a maximum adsorption capacity (Q
max
) of 1299.7 mgg
−1
and the removal percentage of SMX was 98.2% according to the photocatalytic degradation. Fritz-Schlunder model is the best to describe the adsorption of SMX onto Ag
3
PO
4
. Ag
3
PO
4
can be efficiently recycled as an adsorbent using distilled water up to 4 cycles followed by ethanol 70% and turmeric extract. For the recycling of Ag
3
PO
4
as a photocatalyst, 0.1 M NaOH is the best solvent followed by water, ethanol 70%.
Journal Article
Structural, Optical, and Electrical Investigations of Nd2O3-Doped PVA/PVP Polymeric Composites for Electronic and Optoelectronic Applications
by
Samer H. Zyoud
,
Thekrayat H. AlAbdulaal
,
Mohammad S. Al-Assiri
in
Absorption spectra
,
Composite materials
,
Composite structures
2023
In this present work, a PVA/PVP-blend polymer was doped with various concentrations of neodymium oxide (PB-Nd+3) composite films using the solution casting technique. X-ray diffraction (XRD) analysis was used to investigate the composite structure and proved the semi-crystallinity of the pure PVA/PVP polymeric sample. Furthermore, Fourier transform infrared (FT-IR) analysis, a chemical-structure tool, illustrated a significant interaction of PB-Nd+3 elements in the polymeric blends. The transmittance data reached 88% for the host PVA/PVP blend matrix, while the absorption increased with the high dopant quantities of PB-Nd+3. The absorption spectrum fitting (ASF) and Tauc’s models optically estimated the direct and indirect energy bandgaps, where the addition of PB-Nd+3 concentrations resulted in a drop in the energy bandgap values. A remarkably higher quantity of Urbach energy for the investigated composite films was observed with the increase in the PB-Nd+3 contents. Moreover, seven theoretical equations were utilized, in this current research, to indicate the correlation between the refractive index and the energy bandgap. The indirect bandgaps for the proposed composites were evaluated to be in the range of 5.6 eV to 4.82 eV; in addition, the direct energy gaps decreased from 6.09 eV to 5.83 eV as the dopant ratios increased. The nonlinear optical parameters were influenced by adding PB-Nd+3, which tended to increase the values. The PB-Nd+3 composite films enhanced the optical limiting effects and offered a cut-off laser in the visible region. The real and imaginary parts of the dielectric permittivity of the blend polymer embedded in PB-Nd+3 increased in the low-frequency region. The AC conductivity and nonlinear I-V characteristics were augmented with the doping level of PB-Nd+3 contents in the blended PVA/PVP polymer. The outstanding findings regarding the structural, electrical, optical, and dielectric performance of the proposed materials show that the new PB-Nd+3-doped PVA/PVP composite polymeric films are applicable in optoelectronics, cut-off lasers, and electrical devices.
Journal Article
Linear/Nonlinear Optical Characteristics of ZnO-Doped PVA/PVP Polymeric Films for Electronic and Optical Limiting Applications
by
Samer H. Zyoud
,
Thekrayat H. AlAbdulaal
,
Mohammad S. Al-Assiri
in
Analysis
,
Chemical synthesis
,
Constraining
2023
ZnO-doped Polyvinyl alcohol/polyvinyl pyrrolidone (PVA/PVP) polymeric films were prepared in this study through an easy and inexpensive solution-casting method. The scope of the study was based on the structural, dielectric, and optical parameters, as well as on the optical limiting effects of the ZnO-doped polymer blend (PB) as nanocomposite films. The X-ray diffraction (XRD) analysis indicated that the synthesized nanocomposites were semicrystalline. The calculated crystalline size of the polymeric semicrystalline peak decreased as ZnO increased or enhanced the blend polymer. Fourier’s transformer infrared (FT-IR) study confirmed a substantial dispersion of ZnO nanoparticles in a polymeric PVA/PVP matrix. The optical absorption properties suggested focusing on the surface plasmonic peak (SPR). The refractive index values ranged from 1.718 for the pure PB ZnO0 sample in the Hossam, Ibrahim, and Heba model to 3.036 for the PB ZnO5 film from the Anani model. Nonlinear optical parameters (χ((3)), and n(2)) were calculated and analyzed for the PB ZnO nanocomposite films under investigation. The maximum value for χ((1)) was 0.550, while for χ((3)), its susceptibility value was 155.85 × 10−13 esu, and for the nonlinear refractive index (n((2)), it was 20.87 × 10−11 esu. A gradual decrease was revealed in the optical limiting sources, as a high content of ZnO was induced in the blend PVA/PVP polymer. Due to their unique properties, these materials can be used in electronic and optoelectronic devices.
Journal Article
The Auto-Combustion Method Synthesized Eu2O3- ZnO Nanostructured Composites for Electronic and Photocatalytic Applications
by
Manal AlShadidi
,
Vanga Ganesh
,
Samia Nasr
in
Biomedical materials
,
Combustion
,
combustion method; Eu2O3-ZnO nanostructured composites; structural; optical; electrical; photocatalytic activity
2022
An efficient and environmentally friendly combustion technique was employed to produce ZnO nanopowders with different Eu concentrations (from 0.001 g to 5 g). The structural morphology of the Eu2O3-ZnO nanocomposites was examined using XRD, SEM, and infrared spectroscopy (FT-IR). In addition, UV-Vis diffuse reflectance spectroscopy was also used to investigate the effects of europium (Eu) dopant on the optical behaviors and energy bandgaps of nano-complex oxides. The photocatalytic degradation efficiency of phenol and methylene blue was investigated using all the prepared Eu2O3-ZnO nanostructured samples. Photocatalytic effectiveness increased when europium (Eu) doping ratios increased. After adding moderate Eu, more hydroxyl radicals were generated over ZnO. The best photocatalyst for phenol degradation was 1 percent Eu2O3-ZnO, while it was 0.5 percent Eu2O3-ZnO for methylene blue solutions. The obtained Eu2O3-doped ZnO nanostructured materials are considered innovative, promising candidates for a wide range of nano-applications, including biomedical and photocatalytic degradation of organic dyes and phenol.
Journal Article
Enhancement in the Structural, Electrical, Optical, and Photocatalytic Properties of La2O3-Doped ZnO Nanostructures
by
Manal AlShadidi
,
Vanga Ganesh
,
Thekrayat H. AlAbdulaal
in
Alternating current
,
Biomedical materials
,
Catalytic activity
2022
A lanthanum oxide (La2O3)-ZnO nanostructured material was synthesized in the proposed study with different La2O3 concentrations, 0.001 g to 5 g (named So to S7), using the combustion method. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transformation infrared spectroscopy (FT-IR) were utilized for investigating the structure, morphology, and spectral studies of the La2O3- ZnO nanomaterials, respectively. The results obtained from previous techniques support ZnO’s growth from crystalline to nanoparticles’ fine structure by changing the concentrations of lanthanum oxide (La2O3) dopants in the host matrix. The percentage of ZnO doped with La- influences the ZnO photocatalytic activity. SEM analysis confirmed the grain size ranged between 81 and 138 nm. Furthermore, UV-Vis diffuse reflectance spectroscopy was performed to verify the effects of La2O3 dopants on the linear optical properties of the nano-composite oxides. There was a variation in the energy bandgaps of La2O3-ZnO nanocomposites, increasing the weight concentrations of lanthanum dopants. The AC electrical conductivity, dielectric properties, and current–voltage properties support the enactment of the electrical characteristics of the ZnO nanoparticles by adding La2O3. All the samples under investigation were used for photodegradation with Rhodamine B (RhB) and Methylene Blue (MB). In less than 30 min of visible light irradiation, S4 (0.5 g) La2O3-ZnO reached 99% of RhB and MB degradation activity. This study showed the best photocatalytic effect for RhB and MB degradation of 0.13 and 0.11 min−1 by 0.5 g La2O3-ZnO. Recycling was performed five times for the nanocatalysts that displayed up to 98 percent catalytic efficiency for RhB and MB degradation in 30 min. The prepared La2O3-ZnO nanostructured composites are considered novel candidates for various applications in biomedical and photocatalytic studies.
Journal Article
Electrocatalytic Degradation of Rhodamine B Using Li-Doped ZnO Nanoparticles: Novel Approach
by
Bandapelli Ravi Kumar
,
Thekrayat. H. AlAbdulaal
,
Vanga Ganesh
in
Combustion
,
Crystallization
,
Dielectric loss
2023
In this paper, we discuss the preparation of Li-doped ZnO nanostructures through combustion and report on their structural, morphological, optical, and electrocatalysis properties. X-ray diffraction analyses show that the samples have a structure crystallized into the usual hexagonal wurtzite ZnO structure according to the P63mc space group. The scanning electron microscope images conceal all samples’ nanosphere bundles and aggregates. The reflectance spectra analysis showed that the direct bandgap values varied from 3.273 eV (for pure ZnO, i.e., ZnL1) to 3.256 eV (for high Li-doped ZnO). The measured capacitance concerning frequency has estimated the variation of dielectric constant, dielectric loss, and AC conductivity against AC electric field frequency. The dielectric constant variations and AC conductivity are analyzed and discussed by well-known models such as Koop’s phenomenological theory and Jonscher’s law. The Raman spectra have been recorded and examined for the prepared samples. Rhodamine B was electro-catalytically degraded in all prepared samples, with the fastest time for ZnL5 being 3 min.
Journal Article
Fabrication and Characterization of Highly Efficient As-Synthesized WO3/Graphitic-C3N4 Nanocomposite for Photocatalytic Degradation of Organic Compounds
by
Hisham S. M. Abd-Rabboh
,
Ibrahim S. Yahia
,
Abdelfatteh Bouzidi
in
Carbon nitride
,
Catalytic activity
,
Energy gap
2022
The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts’ properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.
Journal Article
Facile Synthesis of Ni-Doped ZnO Nanostructures via Laser-Assisted Chemical Bath Synthesis with High and Durable Photocatalytic Activity
by
Abd El-sadek, Mahmoud S.
,
Abdelkader, Atef F. I.
,
Nasor, Mohamed
in
Analysis
,
Catalytic activity
,
Chemical properties
2023
Pure and Ni-doped (1%, 2%, and 3%) nanostructures were synthesized using a novel laser-assisted chemical bath synthesis (LACBS) technique. For the first time, LACBS was used to create a doping solution utilizing a 7 W blue laser with a 444.4 nm wavelength and a continuous beam. The Ni-doping concentration was varied by changing the amount of Ni precursor added. All samples were analyzed using XRD, SEM, EDX, FTIR, UV–Vis, and photocatalysis tests for photodegradation under blue laser illumination. XRD was used to confirm that the tested ZnO had a hexagonal wurtzite structure. The crystallite size decreased as the Ni-doping concentration rose. EDX experiments were conducted to analyze the elemental characteristics of the pure and Ni-doped (1%, 2%, and 3%) nanostructures. The existence of nanoscale hexagonal structures was confirmed through SEM studies. The band gap values of the pure and Ni-doped ZnO nanostructures decreased as the doping concentration increased. FTIR studies were conducted to examine the functional groups of the pure and doped samples. The produced materials exhibited excellent photocatalytic performance toward the degradation of MB organic dye, an example of a pollutant found in wastewater.
Journal Article
Fast and Excellent Enhanced Photocatalytic Degradation of Methylene Blue Using Silver-Doped Zinc Oxide Submicron Structures under Blue Laser Irradiation
by
Samer H. Zyoud
,
Moyad Shahwan
,
Malek G. Daher
in
Absorption spectra
,
Catalytic activity
,
Chemical properties
2023
In this study, laser-assisted chemical bath synthesis (LACBS) was used to prepare pure and Ag-doped ZnO submicron structures using a simplified hydrothermal approach that did not require a catalyst. The photocatalytic degradation of Methylene Blue was investigated under blue laser irradiation (λ = 444.5 nm and I = 8000 lx). The doping concentration varied (2%, 4%, 6%, 8%, tando 10%) and was prepared by LACBS using a continuous blue laser (P = 7 W, λ = 444.5 nm) for the first time. XRD, FE-SEM, EDX, and UV-Vis investigated the characteristics of the samples produced by the LACBS. ZnO: Ag(10%) submicron flowers are essential in rapid photodegradation under blue laser irradiation. The high surface area and catalytic activity of the prepared Ag-decorated ZnO are attributed to this improved photocatalytic activity. Using UV-visible spectroscopy, the photocatalytic efficiency was determined from the absorption spectra. The separation of photo-generated electron-hole pairs was facilitated, and the absorption edge of the hybrid submicron structures shifted into the visible spectrum region due to a combination of the Ag plasmonic effect and surface imperfections in ZnO. Effective visible light absorption was achieved via band-edge tuning, which increased the ZnO:Ag submicron structures’ ability to degrade dyes.
Journal Article
Impact of Mo-Doping on the Structural, Optical, and Electrocatalytic Degradation of ZnO Nanoparticles: Novel Approach
by
Vanga Ganesh
,
Thekrayat H. AlAbdulaal
,
Mervat I. Mohammed
in
Absorption spectra
,
Chemical properties
,
Combustion synthesis
2022
Pure and Molybdenum (Mo)-doped zinc oxide (ZnO) nanoparticles were prepared by a cost-effective combustion synthesis route. XRD results revealed the decrement in crystallite size of ZnO with an increase in Mo-doping concentration. Optical bandgap (Eg) values were determined using optical reflectance spectra of these films measured in the range of 190–800 nm. The Eg values decreased with increasing the Mo-doping concentration. The dielectric properties of these samples were studied to determine the dielectric constant values. Raman spectra of these samples were recorded to know the structure. These sample absorption spectra were recorded for electrocatalytic applications. All the prepared samples were subjected to electrocatalytic degradation of Rhodamine B. The 0.01 wt% Mo doped ZnO showed 100% in 7 min electrocatalytic degradation.
Journal Article