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1.
Environ Geochem Health ; 46(3): 92, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367085

RESUMO

A facile and cost-effective hydrothermal followed by precipitation method is employed to synthesize visible light-driven ZnS-Ag ternary composites supported on carbon aerogel (CA). Extensive studies were conducted on the structural, morphological, and optical properties, confirming the successful formation of ternary nanocomposites. The obtained results evidently demonstrate the successful loading of ZnS and Ag onto the surface of the CA. High-resolution transmission electron microscopy analysis revealed that ZnS and Ag nanoparticles (AgNPs) were uniformly distributed on the surface of the CA with an average diameter of 18 nm. The biomass-derived CA, containing a hierarchical porous nano-architecture and an abundant number of -NH2 functional groups on the surface, can greatly prevent the agglomeration, stability and reduce particle size. Brunauer-Emmett-Teller analysis results indicated specific surface areas of 4.62 m2 g-1 for the CA, 48.50 m2 g-1 for the CA/ZnS composite, and 62.62 m2 g-1 for the CA/ZnS-Ag composite. These values demonstrate an increase in surface area upon the incorporation of ZnS and Ag into the CA matrix. Under visible light irradiation, the synthesized CA/ZnS-Ag composites displayed remarkably improved photodegradation efficiency of methylene blue (MB). Among the tested samples, the CA/ZnS-Ag composites exhibited the highest percentage of photodegradation efficiency, surpassing ZnS, CA, and CA/ZnS. The obtained percentages of degradation efficiency for CA, ZnS, CA/ZnS, and CA/ZnS-Ag composites were determined as 26.60%, 52.12%, 68.39%, and 98.64%, respectively. These results highlight the superior photocatalytic performance of the CA/ZnS-Ag composites in the degradation of MB under visible light conditions. The superior efficiency of the CA/ZnS-Ag composite can be attributed to multiple factors, including its elevated specific surface area, inhibition of electron-hole pair recombination, and enhanced photon absorption within the visible light spectrum. The CA/ZnS-Ag composites displayed consistent efficiency over multiple cycles, confirming their stable performance, reusability, and enduring durability, thereby showcasing the robust nature of this composite material.


Assuntos
Carbono , Nanopartículas Metálicas , Azul de Metileno/química , Prata/química , Nanopartículas Metálicas/química , Biomassa , Luz
2.
Environ Geochem Health ; 46(3): 95, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38374258

RESUMO

Graphene-based nanocomposites are developing as a new class of materials with several uses. The varied weight percentages of rGO on Ag2S catalysts were synthesized using a simple hydrothermal process and employed for the decomposition of anionic dye naphthol green B (NGB) under solar light. The reduced graphene oxide-based silver sulfide (rGO/Ag2S) nanoparticles were then examined using XRD, SEM, EDS, HR-TEM, XPS, UV-DRS, and PL analysis. Using solar light, the photocatalytic activity of the produced catalyst was examined for the degradation of naphthol green B (NGB) in an aqueous solution. At pH 9, rGO/Ag2S is discovered to be more effective than the other catalysts for the NGB dye mineralization. Analyses have been conducted on the influence of operational parameters on the photo-mineralization of NGB, including the initial pH, initial dye concentration, and catalyst dosage. The dye concentration increased; the efficiency of photocatalytic degradation tended to decrease. Chemical oxygen demand (COD) studies have verified the NGB dye mineralization. Active species trapping revealed that holes, hydroxyl radicals, and superoxide radicals all played major roles in the photocatalytic deterioration of NGB processes. Additionally, a potential mechanism of NGB dye degradation by rGO/Ag2S catalyst is presented. The synthesized compound was further evaluated for antibacterial activity, and the results indicated that rGO/Ag2S were potentially effective antibacterial agents.


Assuntos
Antibacterianos , Compostos Férricos , Nanopartículas , Antibacterianos/farmacologia , Naftalenossulfonatos , Água
3.
Environ Geochem Health ; 46(3): 96, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376605

RESUMO

SrTiO3/Ag nanocomposites were synthesized using a facile wet impregnation method, employing rigorous experimental techniques for comprehensive characterization. XRD, FTIR, UV, PL, FESEM, and HRTEM were meticulously utilized to elucidate their structural, functional, morphological, and optical properties. The electrochemical performance of the SrTiO3/Ag nanocomposite was rigorously assessed, revealing an impressive specific capacitance of 850 F/g at a current density of 1 A. Furthermore, the photocatalytic activity of the SrTiO3/Ag nanocomposite was rigorously examined using methylene blue (MB) dye, and the results were outstanding. After 120 min of UV irradiation, the nanocomposite exhibited an exceptional MB dye degradation efficiency exceeding 88%. The SrTiO3/Ag nanocomposite represents an exemplary catalyst in terms of efficiency, cost-effectiveness, environmental compatibility, and reusability. The electron and superoxide radicals play a chief role in the MB dye degradation process. The inclusion of Ag within the SrTiO3 matrix facilitated the formation of a conductive nano-network, ultimately resulting in superior capacitive and photocatalytic performance.


Assuntos
Poluentes Ambientais , Nanopartículas , Prata , Condutividade Elétrica , Azul de Metileno
4.
Nanomaterials (Basel) ; 13(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687002

RESUMO

This work reports on the photocatalytic activity of tin oxide (SnO2)-doped magnesium (Mg) and fluorine (F) nanoparticles for methyl orange and safranin dye degradation under sunlight irradiation. Nanocatalysis-induced dye degradation was examined using UV-visible spectroscopy and a pseudo-first-order kinetics model. The results indicate that the prepared nanoparticles exhibit superior photocatalytic activity, and the degradation of methyl orange (MO) dye is approximately 82%. In contrast, the degradation of safranin dye is 96% in the same time interval of 105 min. The calculated crystallite size of the SnO2-Mg-F nanocomposite is 29.5 nm, which respects the particle size found in the DLS analysis with a tetragonal structure and spherical morphology affirmed. The optical characteristics were assessed, and their respective bandgap energies were determined to be 3.6 eV. The influence of F in Mg and SnO2 is recognized with the XRD and FT-IR spectra of the prepared particles.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1321, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-21579414

RESUMO

In the title compound, C(27)H(20)ClNO, the quinoline ring forms a dihedral angle of 62.53 (5)° with the substituent benzene ring. In the crystal, inter-molecular C-H⋯Cl inter-actions link the mol-ecules into chains along the b axis. Inter-molecular C-H⋯N and C-H⋯O hydrogen bonds further consolidate the structure into a three-dimensional network. The unit cell contains four solvent-accessible voids, each with a volume of 35 Å(3), but no significant electron density was found in them.

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): o1780, 2010 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-21587992

RESUMO

In the title compound, C(25)H(18)ClNO, the conformation about the C=C double bond is E. Significant twists are evident in the mol-ecule, with the benzene ring forming a dihedral angle of 53.92 (11)° with the quinolinyl residue. Further, the chalcone residue is approximately perpendicular to the quinolinyl residue [C(q)-C(q)-C(c)-O(c) torsion angle = -104.5 (3)°, where q = quinolinyl and c = chalcone]. In the crystal, the presence of C-H⋯O and C-H⋯π inter-actions leads to supra-molecular layers lying parallel to (02).

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