Skip to main content

Enhancement of the photodegradation performance towards methylene blue and rhodamine B using AgxSn1 xO2 nanocomposites

Research Abstract

In the present study, the structural properties, as well as the photodegradation performance of methylene blue (MB) and rhodamine B (Rh B) using hydrothermal synthesized AgxSn1–xO2 (0 ≤ x ≤ 1) nanocomposites were studied. The study was investigated using various techniques including EDS, XRD, FE-SEM, HR-TEM, photoluminescence spectroscopy, N2 adsorption-desorption, GC-MS, and a double-beam spectrophotometer. The tetragonal SnO2 phase dominates, while the cubic Ag2O phase appears at larger x ratios (x ≥ 0.5). The crystallite and particle sizes were slightly raised for a low Ag ratio but dramatically increased for higher x ratios. Different morphologies emerge depending on the composition, such as spherical and irregular particles for x = 0 and 1, sheet-like morphology for x = 0.05, 0.2, and 0.4, and worm-like morphology for x = 0.5. The maximum surface area was calculated using the BET …

Research Authors
Abdelazim M Mebed, Khulaif Alshammari, Mohammed Ezzeldien, SA Al-Ghamdi, Alaa M Abd-Elnaiem, Mohamed Abd El-Aal, Dalia Hamad
Research Date
Research Department
Research Journal
Journal of Alloys and Compounds
Research Pages
176977
Research Publisher
Elsevier
Research Year
2024

Friedel–Crafts chemistry. Part 64. Facile syntheses of fused azepinoindoles by Jourdan–Ullmann and Friedel–Crafts approaches

Research Abstract

Facile and concise procedures for the construction of indole fused N-heterocyclic systems were described. A series of benzo-, pyrido-, thieno-, naphtho-fused azepinoindolones and indolo-azepinoquinolinones has been prepared starting from indol-2-acetic acids. The required starting carboxylic acids 3ae were readily obtained by the N-arylations of indoleacetic acid 1 with various aromatic halides 2ae. Subsequent carboxylic acids were esterified, followed by the addition of Grignard reagents to afford the corresponding indole-based alcohols 5ae. The key step in this protocol is the Friedel–Crafts cyclisations of these precursors promoted by AlCl3/CH3NO2 or trifluoromethanesulfonic acid (TfOH) or polyphosphoric acid (PPA) catalysts to form the desired condensed indoles in moderate to good yields.

Research Authors
Hassan Abdou kotb Abd El-Aal
Research Date
Research Department
Research Journal
Australian Journal of Chemistry
Research Pages
1-15
Research Publisher
CSIRO PUBLISHING
Research Website
https://www.publish.csiro.au/CH/CH25003
Research Year
2025

Copper @ eggshell nanocomposite/chitosan gelified carbon paste electrode as an electrochemical biosensor for l-tyrosine analysis as a biomarker in the serum of normal and liver disease patients

Research Abstract

L-Tyrosine (L-Tyr), an amino acid, has emerged as a potential biomarker for the detection and monitoring of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). By analysing the serum levels of L-Tyr, healthcare pro­ fessionals can gain insights into the progression and development of these liver diseases. The utilization of L-Tyr as a biomarker holds potential for early detection and timely intervention, improving patient outcomes and treatment options. In this study we developed a novel nanocomposite based on eggshell waste and copper nanoparticles to modify carbon paste electrode (CPE) using chitosan gel as a binder for sensitive estimation of LTyr in human serum samples. The use of chitosan gel avoids the insulating effect of paraffin oil that was usually used for fabrication of CPE and enhance the sensitivity and selectivity of the modified electrode. Square wave voltammetry (SWV) was used to optimize the electrochemical parameters of the oxidation of L-Tyr onto the surface of the fabricated electrode (CuNPs@ESh/CS/CPE). The prepared composite was characterized using Xray diffraction (XRD), Fourier Transform - Infrared spectroscopy (FT-IR), UV–VIS spectroscopy and scan elec­ tron microscopy (SEM) and electrochemical impedence spectroscopy (EIS). The fabricated biosensor could es­ timate L-Tyr levels in controls, LC and HCC patients’ serum with high accuracy and sensitivity. The obtained results demonstrated the presence of significant difference in L-Tyr levels in the three studied groups. This in­ dicates that L-Tyr amino acid may serve as a crucial biomarker for the evaluation of such liver diseases.
 

Research Authors
Rania M. Kamel, Fatma A.M. Abdel-aal, Fardous A. Mohamed, Asmaa Abdeltawab, Mohamed O. Abdel-Malek, Aly A. Othman, Abdel-Maaboud I. Mohamed
Research Date
Research Department
Research Journal
Microchemical Journal
Research Year
2024

Analysis of geomechanical properties for evaluation of the Cretaceous reservoirs using well logging data in the Silah field, El-Gindi basin, North Western Desert, Egypt

Research Abstract

The geomechanical properties of the Silah field were measured to identify the various types of rocks in the area and to determine the economically valuable zones with good petrophysical properties. A suite of well logging data was interpreted to delineate the subsurface lithostratigraphic units and permeable reservoirs across the two drilled wells. The estimated geomechanical parameters (compressional sonic velocity, shear sonic velocity, acoustic impedance, and Poisson's ratio) and certain petrophysical parameters (porosity and shale volume) were computed using empirical relations. This study aims to characterize and evaluate the sedimentary rock units of the field to delineate potential hydrocarbon reservoir formations based on their geomechanical and petrophysical properties. The well logging data interpretation and geomechanical properties analysis reveal that the subsurface lithostratigraphy comprises four types of lithology: sand, carbonate (limestone and dolomite), siltstone, and shale, interbedded. The main interesting reservoirs are in the Kharita, Bahariya, and Abu Roash (G and F members). The different constructed geomechanical crossplots indicate that the main lithology consists of shaley sandstone to sandstone and carbonates, with the shale type varying from predominantly laminated to partly dispersed. The results show that Larionov shale volume values (9.6% to 32%), total porosity ranged 10% to 26%, the compressional to shear wave velocity ratio (Vp/Vs) ranges from 1.58 to 1.912, and Poisson’s ratio values vary from 0.171 to 0.306. Also, the effective porosity ranges from 3.7%- 19.3%. There is a substantial bed of shale beneath and above these zones, which serves as a possible source and/or seal rock.

Research Authors
Mohamed Osman Ebraheem1 , Hamza Ahmed Ibrahim2 and Ahmed Hosny Senosy1
Research Date
Research Department
Research Journal
New Valley University Journal of Basic and Applied Sciences [NUJBAS]
Research Member
Research Pages
17-40
Research Publisher
New Valley University Journal of Basic and Applied Sciences [NUJBAS]
Research Vol
3, No. 2
Research Year
2025

Laser power-induced Fermi-level shift in graphene/Al2O3 under ambient atmosphere: Toward neutralizing unintentional graphene doping

Research Abstract

Manipulating unintentional doping in graphene layers, which is influenced by environmental factors and supporting substrates, is of significant concern for the performance and advancement of graphene-based devices. In this context, laser-induced tuning of charge carriers in graphene facilitates the exploration of graphene’s properties in relation to its surroundings and enables laser-assisted functionalization. This has the potential to advance optoelectronic devices that utilize graphene on transparent dielectric substrates, such as Al 2 O 3. In this work, laser power (P L) in Raman spectroscopy is used as a convenient contactless tool to manipulate and control unintentional carrier concentration and Fermi level position (E F) in graphene/α-Al 2 O 3 (G/Al 2 O 3) under ambient conditions. Samples are annealed at 400 C for two hours in an (Ar+ H 2) atmosphere to remove any chemical residues. Analysis of the peak …

Research Authors
Jamal QM Almarashi, Mohamed K Zayed, Hesham Fares, Heba Sukar, Takao Ono, Yasushi Kanai, Mohamed Almokhtar
Research Date
Research Department
Research Journal
Chinese Physics B
Research Pages
066302
Research Publisher
IOP Publishing
Research Year
2025

Fano resonance-boosted topological sensor for next-generation sensing

Research Abstract

The rapidly developing field of topological photonics has the potential to revolutionize the design and operation of optical systems. This study presents a novel approach for constructing a resilient sensor based on topological resonance. The coupling of the photonic crystal waveguide (PCW) with the topological corner state (TCS) within the structure forms the proposed sensor. The PCW provides a well-defined propagating mode, while the TCS is a localized mode that is topologically protected against perturbations. The coupling between the two modes contributes growth to a Fano resonance and results in a sharp and narrow spectral feature sensitive to the refractive index variation of the surrounding medium. The proposed sensor possesses a high sensitivity of ∼461.96 nm/RIU with a high Q-factor \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts …

Research Authors
Mohamed Almokhtar Mohamed
Research Date
Research Department
Research Journal
Optical and Quantum Electronics
Research Pages
127
Research Publisher
Springer US
Research Year
2025

Multifunctional topological photonic crystal device for multichannel frequency routing and highly sensitive refractive index sensing

Research Authors
Naglaa AbdelAll, Mohamed Almokhtar, Ghada Khouqeer, Mohamed Saleh M Esmail, Israa Abood, Sayed El Soliman
Research Date
Research Department
Research Journal
Physica Scripta
Research Vol
99
Research Year
2024

Synthesis, characterization, and optical sensing of hydrophilic anodic alumina films

Research Abstract

Abstract Herein, the anodization of 2.6 μm Al-0.2 at.% Cu (Al-0.2 Cu) films on TiN/p-type Si substrate were performed using common acidic mediums at different ranges of anodization voltage (V a) to produce porous anodic alumina (PAA) nanostructures with high porosity. The anodization of Al-0.2 Cu in 1 M H 2 SO 4 at V a range of 10–30 V produced a higher oxide thickness, and hence, a higher volume expansion factor, compared to the anodization in 0.75 M H 3 PO 4 at V a range of 100–140 V. The increase in V a, as expected, increases the inter-pore distance, pore size, and porosity of the PAA and improves the anodization rate. The optical sensing performance of the synthesized PAA under different conditions was investigated. The maximum surface wettability was attained for PAA anodized in 1 M H 2 SO 4 at 20 and 30 V. Moreover, the Vickers hardness (HV) of PAA was improved by forming a thin alumina …

Research Authors
Mohamed Almokhtar Mohamed
Research Date
Research Department
Research Journal
Optical Materials
Research Pages
116390
Research Publisher
North-Holland
Research Year
2024

Rainbow trapping with engineered topological corner states and cavities in photonic crystals

Research Authors
Naglaa AbdelAll, Mohamed Almokhtar, Ghada Khouqeer, Israa Abood, Sayed El. Soliman
Research Date
Research Department
Research Journal
Advanced Quantum Technologies
Research Vol
7
Research Year
2024

Electrodeposition of a novel porous, crystalline Cd-rich CdS nanonoodles on ZnO nanosheets for enhanced solar light-driven water splitting

Research Abstract

Solar light-driven water splitting offers a sustainable pathway for energy conversion. This study presents a straightforward electrodeposition method for decorating ZnO nanosheets with CdS nanonoodles, varying the deposition time. Structural and morphological analysis confirmed the formation of a crystalline, Cd-rich hexagonal CdS phase on the ZnO nanosheets, exhibiting a unique nanonoodles morphology. The thickness of the CdS/ZnO nanonoodles gradually increased to 30 μm with extended deposition times. Notably, the valence band of the hybrid CdS/ZnO nanonoodles exhibit a lower binding energy compared to both CdS nanonoodles and ZnO nanosheets, highlighting interfacial charge transfer and enhanced synergy. The hybrid CdS/ZnO nanonoodle photoanode, fabricated with a 60-min deposition time, exhibits a reduced band gap of 2.8 eV compared to the 3.2 eV band gap of the pristine ZnO nanosheets. This reduction in the band gap indicates enhanced solar light absorption capabilities. The CdS/ZnO nanonoodles demonstrate a gradual improvement in the photoelectrochemical water splitting efficiency with increasing deposition time. The hybrid photoanode achieves a remarkable photocurrent density of 9.49 mA cm−2 at 1.23 V vs. reversible hydrogen electrode (RHE), representing a 20-fold increase compared to the ZnO nanosheets (0.46 mA cm−2) and a 7-fold increase compared to the CdS nanonoodles (1.45 mA cm−2). This heterostructured CdS/ZnO nanonoodles hybrid photoanode achieves an impressive conversion efficiency of 9.21 % at 0.4 V vs. RHE.

Research Authors
A.G. Abd-Elrahim, Manar A. Ali, Doo-Man Chun
Research Date
Research Department
Research Journal
Journal of Power Sources
Research Pages
237950
Research Publisher
Elsevier
Research Rank
International Journal
Research Vol
655
Research Website
https://doi.org/10.1016/j.jpowsour.2025.237950
Research Year
2025
Subscribe to