Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Luminescence ; 39(6): e4799, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38858760

RESUMEN

In this study, tellurium-doped and undoped metal oxide nanoparticles (NPs) (ZnO, Mn3O4, SnO2) are compared, and a practical method for their synthesis is presented. Nanocomposites were created using the coprecipitation process, and comparisons between the three material categories under study were made using a range of characterization methods. The produced materials were subjected to structural, morphological, elemental composition, and functional group analyses using XRD, FESEM in combination with EDS, and FTIR. The optical characteristics in terms of cutoff wavelength were evaluated using UV-visible spectroscopy. Catalyzing the breakdown of methylene blue (MB) dye, the isolated nanocomposites demonstrated very consistent behavior when utilized as catalysts. Regarding both doped and undoped ZnO NPs, the maximum percentage of degradation was found to be 98% when exposed to solar Escherichia coli and Staphylococcus aureus, which stand for gram-positive and gram-negative bacteria, respectively, and were chosen as model strains for both groups using the disk diffusion technique in the context of in vitro antibacterial testing. Doped and undoped ZnO NPs exhibited greater antibacterial efficacy, with significant inhibition zones measuring 31.5 and 37.8 mm, compared with other metal oxide NPs.


Asunto(s)
Antibacterianos , Escherichia coli , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Telurio , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Telurio/química , Telurio/farmacología , Staphylococcus aureus/efectos de los fármacos , Catálisis , Nanopartículas del Metal/química , Escherichia coli/efectos de los fármacos , Procesos Fotoquímicos , Azul de Metileno/química , Azul de Metileno/farmacología , Óxido de Zinc/química , Óxido de Zinc/farmacología , Manganeso/química , Manganeso/farmacología , Estaño/química , Estaño/farmacología , Tamaño de la Partícula , Óxidos/química , Óxidos/farmacología
2.
Luminescence ; 39(5): e4758, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712530

RESUMEN

The ability of heterogeneous photocatalysis to effectively remove organic pollutants from wastewater has shown great promise as a tool for environmental remediation. Pure zinc ferrites (ZnFe2O4) and magnesium-doped zinc ferrites (Mg@ZnFe2O4) with variable percentages of Mg (0.5, 1, 3, 5, 7, and 9 mol%) were synthesized via hydrothermal route and their photocatalytic activity was checked against methylene blue (MB) taken as a model dye. FTIR, XPS, BET, PL, XRD, TEM, and UV-Vis spectroscopy were used for the identification and morphological characterization of the prepared nanoparticles (NPs) and nanocomposites (NCs). The 7% Mg@ZnFe2O4 NPs demonstrated excellent degradation against MB under sunlight. The 7% Mg@ZnFe2O4 NPs were integrated with diverse contents (10, 50, 30, and 70 wt.%) of S@g-C3N4 to develop NCs with better activity. When the NCs were tested to degrade MB dye, it was revealed that the 7%Mg@ZnFe2O4/S@g-C3N4 NCs were more effective at utilizing solar energy than the other NPs and NCs. The synergistic effect of the interface formed between Mg@ZnFe2O4 and S@g-C3N4 was primarily responsible for the boosted photocatalytic capability of the NCs. The fabricated NCs may function as an effective new photocatalyst to remove organic dyes from wastewater.


Asunto(s)
Compuestos Férricos , Azul de Metileno , Compuestos de Nitrógeno , Energía Solar , Contaminantes Químicos del Agua , Zinc , Catálisis , Contaminantes Químicos del Agua/química , Compuestos Férricos/química , Azul de Metileno/química , Zinc/química , Magnesio/química , Fotólisis , Procesos Fotoquímicos , Colorantes/química , Nanocompuestos/química , Grafito/química , Aguas Residuales/química , Nitrilos/química
3.
Luminescence ; 39(2): e4693, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38403841

RESUMEN

The construction of SnO2 nanoparticles (NPs), specifically Te-doped SnO2 NPs, using a simple and economical co-precipitation technique has been thoroughly described in this work. NH3 served as the reducing agent in this procedure, whilst polyethylene glycol served as the capping agent. The primary goals of our work were to investigate the physicochemical properties of the synthesized SnO2 NPs and assess their potential use as antibacterial agents and photocatalysts. Scanning electron microscopy-energy dispersive X-ray, ultraviolet light, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and other analytical techniques were used to thoroughly analyze the NPs. Based on the full width at half maximum of the most noticeable peaks in the XRD spectrum, the Debye-Scherrer equation was used to calculate the crystallite sizes, which indicated the presence of a single tetragonal SnO2 phase. Particularly noteworthy was the exceptional photocatalytic activity of graphene-assisted Te-doped SnO2 NPs, achieving an impressive decomposition efficiency of up to 98% in the photo-oxidation of methylene blue. Furthermore, our investigation delved into the antibacterial attributes of the synthesized SnO2 NPs against Escherichia coli and Staphylococcus aureus, demonstrating inhibitory effects on both bacteria strains. This suggests potential applications for these NPs in various environmental and medical contexts.


Asunto(s)
Nanopartículas del Metal , Azul de Metileno , Fotólisis , Azul de Metileno/química , Telurio , Nanopartículas del Metal/química , Antibacterianos/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
4.
Luminescence ; 39(3): e4724, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38523053

RESUMEN

For white light-rendering research activities, interpretation by using colored emitting materials is an alternative approach. But there are issues in designing the white color emitting materials. Particularly, differences in thermal and decay properties of discrete red, green, and blue emitting materials led to the quest for the search of a single-phased material, able to emit primary colors for white light generation. The current study is an effort to design a simple, single-phase, and cost-effective material with the tunable emission of primary colors by a series of Mg1-xBaxAl2O4:Mn2+ nanopowders. Doping of manganese ion (Mn2+) in the presence of the larger barium cation (Ba2+) at tetrahedral-sites of the spinel magnesium aluminate (MgAl2O4) structure led to the creation of antisite defects. Doped samples were found to have lower bandgaps compared with MgAl2O4, and hybridization of 3d-orbitals of Mn2+ with O(2p), Mg(2s)/Al(2s3p) was found to be responsible for narrowing the bandgap. The distribution of cations at various sites at random results in a variety of electronic transitions between the valance band and oxygen vacancies as well as electron traps produced the antisite defects. The suggested compositions might be used in white light applications since they have three emission bands with centers at 516 nm (green), 464 nm (blue) and 622 nm (red) at an excitation wavelength of 380 nm. A detailed discussion to analyze the effects of the larger cationic radius of Ba2+ on the lattice strain, unit cell parameters, and cell volumes using X-ray diffraction analysis is presented.


Asunto(s)
Óxido de Aluminio , Óxido de Magnesio , Cristalografía por Rayos X , Electrónica
5.
Artículo en Inglés | MEDLINE | ID: mdl-38627345

RESUMEN

Membrane separation technology in the last 40 years has experienced impressive growth, displacing conventional separation processes due to inherent advantages such as less capital investment, and energy efficiency and the devices were simple, compact, and modular. In the current work, we aimed to synthesize a thin-sheet nanofiltration membrane using chitosan (CS), poly(vinyl) alcohol (PVA), and montmorillonite nanoclay (MMT) for copper removal from aqueous solution. Thermogravimetric analysis and differential scanning calorimetry were employed to evaluate the thermal stability of a novel organic-inorganic hybrid membrane. The tensile strength was measured over a wide range of temperatures and pressure to determine its stability. The surface and cross-section morphology of the membrane were studied through scanning electron microscopy. The prepared membrane was then tested for filtration efficiency by adjusting parameters such as pH, pressure, metal ion concentration, and membrane thickness. A mechanism was proposed to explain the hooking of copper ions with the as-prepared membrane after spectral images, such as EDAX and FT-IR, were compared both before and after filtration.

6.
Sci Rep ; 14(1): 2897, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316840

RESUMEN

The investigation focused on creating and studying a new 2D-2D S-scheme CdS/g-C3N4 heterojunction photocatalyst. Various techniques examined its structure, composition, and optical properties. This included XRD, XPS, EDS, SEM, TEM, HRTEM, DRS, and PL. The heterojunction showed a reduced charge recombination rate and more excellent stability, helping to lessen photocorrosion. This was due to photogenerated holes moving more quickly out of the CdS valence band. The interface between g-C3N4 and CdS favored a synergistic charge transfer. A suitable flat band potential measurement supported enhanced reactive oxygen species (ROS) generation in degrading 4-nitrophenol and 2-nitrophenol. This resulted in remarkable degradation efficiency of up to 99% and mineralization of up to 79%. The findings highlighted the practical design of the new 2D-2D S-scheme CdS/g-C3N4 heterojunction photocatalyst and its potential application in various energy and environmental settings, such as pollutant removal, hydrogen production, and CO2 conversion.

7.
Sci Rep ; 14(1): 2499, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291095

RESUMEN

Diabetes is a serious health issue that can be a great risk factor related to numerous physical problems. A class of drugs "Gliflozin" especially Sodium Glucose Co. Transporter 2 was inhibited by a novel drug, which is known as "empagliflozin". While ZnO nanoparticles (NPs) had considerable promise for combating diabetes, it was employed in the treatment and management of type-2 diabetes mellitus. The new drug empagliflozin was initially incorporated into Zinc Oxide NPs in this study using the surface physio-sorption technique, and the degree of drug adsorption was assessed using the HPLC method. The tailored product was characterized by using the FTIR, EDX, Ultraviolet-Visible, XRD and SEM techniques. With an average particle size of 17 nm, SEM revealed mono-dispersion of NPs and sphere-like form. The Freundlich isotherm model best fits and explains the data for the physio-sorption investigation, which examined adsorption capabilities using adsorption isotherms. The enzymes α-amylase and α-glucosidase, which are involved in the human metabolism of carbohydrates, were used in the in-vitro anti-diabetic assays. It was discovered that the composite showed the highest levels of 81.72 and 92.77% inhibition of -α-amylase and -glucosidase at an absolute concentration of 1000 µg per ml with IC50 values of 30.6 µg per ml and 72 µg per ml.


Asunto(s)
Compuestos de Bencidrilo , Diabetes Mellitus Tipo 2 , Glucósidos , Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Humanos , Óxido de Zinc/farmacología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , alfa-Amilasas , Antibacterianos/farmacología , Extractos Vegetales
8.
Nanomaterials (Basel) ; 9(10)2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31652537

RESUMEN

Nanostructured photoanodes are attractive materials for hydrogen production via water photo-electrolysis process. This study focused on the incorporation of carbon quantum dots doped with nitrogen as a photosensitizer into mesoporous tungsten trioxide photoanodes (N-CQD/meso-WO3) using a surfactant self-assembly template approach. The crystal structure, composition, and morphology of pure and N-CQD- modified mesoporous WO3 photoanodes were investigated using scanning electron and transmission microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Due to their high surface area, enhanced optical absorption, and charge-carrier separation and transfer, the resulting N-CQD/meso-WO3 photoanodes exhibited a significantly enhanced photocurrent density of 1.45 mA cm-2 at 1.23 V vs. RHE under AM 1.5 G illumination in 0.5 M Na2SO4 without any co-catalysts or sacrificial reagent, which was about 2.23 times greater than its corresponding pure meso-WO3. Moreover, the oxygen evolution onset potential of the N-CQD/meso-WO3 photoanodes exhibited a negative shift of 95 mV, signifying that both the charge-carrier separation and transfer processes were promoted.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA