Controlled Growth of Silver Oxide Nanoparticles on the Surface of Citrate Anion Intercalated Layered Double Hydroxide

Silver oxide nanoparticles with controlled particle size were successfully obtained utilizing citrate-intercalated layered double hydroxide (LDH) as a substrate and Ag+ as a precursor. The lattice of LDH was partially dissolved during the reaction by Ag+. The released hydroxyl and citrate acted as a reactant in crystal growth and a size controlling capping agent, respectively. X-ray diffraction, X-ray photoelectron spectroscopy, and microscopic measurements clearly showed the development of nano-sized silver oxide particles on the LDH surface. The particle size, homogeneity and purity of silver oxide were influenced by the stoichiometric ratio of Ag/Al. At the lowest silver ratio, the particle size was the smallest, while the chemical purity was the highest. X-ray photoelectron spectroscopy and UV-vis spectroscopy results suggested that the high Ag/Al ratio tended to produce silver oxide with a complex silver environment. The small particle size and homogeneous distribution of silver oxide showed advantages in antibacterial efficacy compared with bulk silver oxide. LDH with an appropriate ratio could be utilized as a substrate to grow silver oxide nanoparticles with controlled size with effective antibacterial performance.

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A New Approach for the Green Biosynthesis of Silver Oxide Nanoparticles Ag2O, Characterization and Catalytic Application

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.16.3.11577.651-660 ◽

2021 ◽

Vol 16 (3) ◽

pp. 651-660

Author(s):

Brahim El-Ghmari ◽

Hanane Farah ◽

Abdellah Ech-Chahad

Keyword(s):

Silver Oxide ◽

Spherical Shape ◽

Wild Plant ◽

Blue Dye ◽

Oxide Nanoparticles ◽

Green Approach ◽

Vis Spectroscopy ◽

Ftir Spectral Analysis ◽

Silver Oxide Nanoparticles ◽

The Stability

In this paper, a facile and green approach for the synthesis of silver oxide nanoparticles Ag2O NPs was performed using the extract of the wild plant Herniaria hirsuta (H. hirsuta). Different spectral methods were used for the characterization of the biosynthesized Ag2O NPs, ultraviolet-visible (UV-Vis) spectroscopy gave a surface plasmon resonance (SPR) peak of Ag2O NPs is 430 nm, estimation of direct and indirect forbidden gap bands are respectively 3.76 eV and 3.68 eV; Fourier transform infrared (FTIR) spectral analysis revealed the groups responsible for the stability and synthesis of Ag2O NPs. The morphology of Ag2O NPs was studied by scanning electron microscopy (SEM) showing a nearly spherical shape of Ag2O NPs, and X-ray diffraction (XRD) study confirmed the crystallinity of Ag2O NPs with a crystallinity size of 15.51 nm. The catalytic activity of Ag2O NPs, as well as the rings number were studied by the degradation of methylene blue dye. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Synthesis, Characterization and Photocatalytic Performance of Calcined ZnCr-Layered Double Hydroxides

Nanomaterials ◽

10.3390/nano11113051 ◽

2021 ◽

Vol 11 (11) ◽

pp. 3051

Author(s):

Somia Djelloul Bencherif ◽

Juan Jesús Gallardo ◽

Iván Carrillo-Berdugo ◽

Abdellah Bahmani ◽

Javier Navas

Keyword(s):

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Textural Properties ◽

Operational Parameters ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Crystal Violet Dye ◽

Double Hydroxide ◽

Double Hydroxides

The development of new materials for performing photocatalytic processes to remove contaminants is an interesting and important research line due to the ever-increasing number of contaminants on our planet. In this sense, we developed a layered double hydroxide material based on Zn and Cr, which was transformed into the corresponding oxide by heat treatment at 500 °C. Both materials were widely characterized for their elemental composition, and structural, morphological, optical and textural properties using several experimental techniques such as x-ray diffraction, x-ray photoelectron spectroscopy, scanning and transmission electron microscopy, Fourier transform infrared spectroscopy, UV-vis spectroscopy and physisorption techniques. In addition, the photocatalytic activity of both materials was analysed. The calcined one showed interesting photocatalytic activity in photodegradation tests using crystal violet dye. The operational parameters for the photocatalytic process using the calcined material were optimised, considering the pH, the initial concentration of the dye, the catalyst load, and the regeneration of the catalyst. The catalyst showed good photocatalytic activity, reaching a degradation of 100% in the optimised conditions and showing good performance after five photodegradation cycles.

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Synthesis and Characterization of Alkali Free Mg-Al Layered Double Hydroxide for Transesterification of Waste Cooking Oil to Biodiesel: Effect of Mg/Al Ratio

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.14.27518 ◽

2019 ◽

Vol 7 (4.14) ◽

pp. 154

Author(s):

Erma Hafiza Ibrahim ◽

Nazrizawati Ahmad Tajuddin ◽

Noraini Hamzah

Keyword(s):

Particle Size ◽

Layered Double Hydroxide ◽

Fossil Fuels ◽

Waste Cooking Oil ◽

Environmental Benefits ◽

Biodiesel Production ◽

X Ray ◽

Cooking Oil ◽

Co Precipitation ◽

Double Hydroxide

The depletion of fossil fuels and the concerned toward environmental sustainability have created a considerable to alternate development of sources of energy as substitute for traditional fossil fuels. The biodiesel production has been reported to be an ideal solution as alternative diesel fuel due to its environmental benefits. Thus, the transesterification of waste cooking oil with methanol in the presence of Mg-Al layered double hydroxide (LDHs) as a heterogeneous catalyst was studied to produce the biodiesel. In this work, Mg-Al-LDH was fabricated via alkali free co-precipitation method with final Mg/Al ratio of 4:1, 3:1 and 2:1. The product of co-precipitation was undergone aging process for 24 h. Then it was placed in oven at 100 ⁰C overnight and finally was calcined at 450 ⁰C for 5 h. The correlation of crystallinity, morphology and particle size of Mg-Al-LDH before and after calcined were examined and compared. X-ray diffraction analyse (XRD) was used to study the textural and structural characteristics of the samples. Particle size, morphology and particle properties were characterize by Brunauer, Emmett and Teller (BET) and Scanning electron spectroscopy (SEM). The bonding and structural of Mg-Al-LDH was studied by Fourier transform infrared spectroscopy (FTIR). Energy dispersive X-ray spectroscopy (EDX) was used for the elemental analysis of the samples. The catalytic activity was evaluated by the transesterification reaction under the following reaction condition: temperature (60 ⁰C-65 ⁰C), time (24 h) and methanol to oil ratio (15:1) .The greatest yield was 85.2% and obtained with combination of 4:1 Mg/Al ratio followed by 3:1 and 2:1 ratio.

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Study of mesoporous CdS-quantum-dot-sensitized TiO2 films by using X-ray photoelectron spectroscopy and AFM

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.5.6 ◽

2014 ◽

Vol 5 ◽

pp. 68-76 ◽

Cited By ~ 45

Author(s):

Mohamed Nawfal Ghazzal ◽

Robert Wojcieszak ◽

Gijo Raj ◽

Eric M Gaigneaux

Keyword(s):

Particle Size ◽

Photoelectron Spectroscopy ◽

Band Gap Energy ◽

Cds Nanoparticles ◽

X Ray ◽

Layer Adsorption ◽

Vis Spectroscopy ◽

Cds Quantum Dot ◽

Afm Analysis ◽

Reaction Processes

CdS quantum dots were grown on mesoporous TiO2 films by successive ionic layer adsorption and reaction processes in order to obtain CdS particles of various sizes. AFM analysis shows that the growth of the CdS particles is a two-step process. The first step is the formation of new crystallites at each deposition cycle. In the next step the pre-deposited crystallites grow to form larger aggregates. Special attention is paid to the estimation of the CdS particle size by X-ray photoelectron spectroscopy (XPS). Among the classical methods of characterization the XPS model is described in detail. In order to make an attempt to validate the XPS model, the results are compared to those obtained from AFM analysis and to the evolution of the band gap energy of the CdS nanoparticles as obtained by UV–vis spectroscopy. The results showed that XPS technique is a powerful tool in the estimation of the CdS particle size. In conjunction with these results, a very good correlation has been found between the number of deposition cycles and the particle size.

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Layered Double Hydroxide Clusters as Precursors of Novel Multifunctional Layers: A Bottom-Up Approach

Coatings ◽

10.3390/coatings9050328 ◽

2019 ◽

Vol 9 (5) ◽

pp. 328 ◽

Cited By ~ 5

Author(s):

Cristina S. Neves ◽

Alexandre C. Bastos ◽

Andrei N. Salak ◽

Maksim Starykevich ◽

Daisy Rocha ◽

...

Keyword(s):

Layered Double Hydroxide ◽

Photoelectron Spectroscopy ◽

Structural Changes ◽

Optical Emission ◽

Localized Corrosion ◽

Emission Spectrometry ◽

Water Contact ◽

X Ray ◽

Xrd Diffraction ◽

Double Hydroxide

The specific microstructure of aluminum alloys is herein explored to grow spatially-resolved layered double hydroxide (SR-LDH) clusters on their surface. Upon chemical modification of LDHs via intercalation, adsorption and grafting with different functional molecules, novel surface-engineered surfaces were obtained. Crystal structure and phase composition were analyzed by X-ray diffraction (XRD) and surface morphology was observed by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) and glow discharge optical emission spectrometry (GDOES) were used to correlate structural changes upon ion-exchange and interfacial modifications with chemical composition and surface profiles of the SR-LDH films, respectively. The protection conferred by these films against localized corrosion was investigated at microscale using the scanning vibrating electrode technique (SVET). LDH-NO3 phase was obtained by direct growth onto AA2024 surface, as evidenced by (003) and (006) XRD diffraction reflections. After anion exchange of nitrate with 2-mercaptobenzothiazole (MBT) there was a decrease in the SR-LDH thickness inferred from GDOES profiles. The subsequent surface functionalization with HTMS was confirmed by the presence of Si signal in XPS and GDOES analyses, leading to an increase in the water contact angle (c.a 144° ± 3°). SVET measurements of the SR-LDH films revealed exceptional corrosion resistance, whereas the bioluminescent bacteria assay proved the anti-microbial character of the obtained films. Overall the results obtained show an effective corrosion protection of the SR-LDHs when compared to the bare substrate and the potential of these films for biofouling applications as new Cr-free pre-treatments.

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A novel polyhedral oligomeric silsesquioxane-modified layered double hydroxide: preparation, characterization and properties

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.284 ◽

2018 ◽

Vol 9 ◽

pp. 3053-3068 ◽

Cited By ~ 4

Author(s):

Xianwei Zhang ◽

Zhongzhu Ma ◽

Hong Fan ◽

Carla Bittencourt ◽

Jintao Wan ◽

...

Keyword(s):

Electron Microscopy ◽

Heat Release ◽

Layered Double Hydroxide ◽

Photoelectron Spectroscopy ◽

Degradation Kinetics ◽

Polyhedral Oligomeric Silsesquioxane ◽

Step Method ◽

X Ray ◽

Double Hydroxide ◽

Oligomeric Silsesquioxane

A novel layered double hydroxide modified by octa-substituted carboxy-terminated polyhedral oligomeric silsesquioxane was prepared via a one-step method and characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, elemental analysis, thermogravimetric analysis, and microscale combustion calorimetry (MCC). Results showed that the silsesquioxane modified-LDH (OLDH) revealed an increase in the interlayer distance, nanoscale plate-like morphology of primary particles, and improved thermal stability. A synergistic effect between the siloxane moiety and Mg–Al hydroxide was found during thermal degradation, and confirmed by the study of degradation kinetics together with the analysis of the surface morphologies and elemental components of char residues. Moreover, in contrast to conventional organic modified LDH (e.g., dodecylbenzenesulfonate-LDH), the MCC results showed a significant decrease in the heat release rate and total heat release, indicating the low flammability of OLDH.

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Synthesis of CoAl-layered double hydroxide/graphene oxide nanohybrid and its reinforcing effect in phenolic foams

High Performance Polymers ◽

10.1177/0954008317716976 ◽

2017 ◽

Vol 30 (6) ◽

pp. 688-698 ◽

Cited By ~ 5

Author(s):

Zhengzhou Wang ◽

Xiaoyan Li

Keyword(s):

Thermal Stability ◽

Graphene Oxide ◽

Layered Double Hydroxide ◽

Photoelectron Spectroscopy ◽

Limiting Oxygen Index ◽

X Ray ◽

Cone Calorimeter Test ◽

Compressive And Flexural Strengths ◽

Double Hydroxide ◽

Thermal Stability Of

A graphene oxide (GO) immobilized with layered double hydroxide (CoAl-LDH/GO) nanohybrid was prepared via a hydrothermal method and characterized by transmission electron microscopy, field emission scan electronic microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and thermogravimetric analysis (TGA). The TGA results show that the immobilization of CoAl-LDH nanoparticles on GO surface greatly promotes the thermal stability of GO. More importantly, the incorporation of the CoAl-LDH/GO nanohybrid into PF foams leads to not only a great improvement in their mechanical strengths but also a reduction in their brittleness and friability. Specifically, compared to neat phenolic (PF) foam, at only 0.9 phr (parts per hundred of resin by mass) of CoAl-LDH/GO, the compressive and flexural strengths of the modified PF foam increase by 54.8% and 35.2%, respectively, and pulverization ratio decreases by 55.2%. The addition of the CoAl-LDH/GO nanohybrid also results in an increase in the limiting oxygen index and a decrease in the peak heat release of the modified PF foam in cone calorimeter test. Moreover, the thermal stability of the PF foam is enhanced by the addition of the nanohybrid.

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Quantum-Sized Zinc Oxide Nanoparticles Synthesised within Mesoporous Silica (SBA-11) by Humid Thermal Decomposition of Zinc Acetate

Crystals ◽

10.3390/cryst10060549 ◽

2020 ◽

Vol 10 (6) ◽

pp. 549

Author(s):

Tariq Aqeel ◽

Heather F. Greer

Keyword(s):

Zinc Oxide ◽

Mesoporous Silica ◽

Photoelectron Spectroscopy ◽

Zinc Acetate ◽

Zinc Oxide Nanoparticles ◽

Mesoporous Structure ◽

Oxide Nanoparticles ◽

Basic Solution ◽

X Ray ◽

Vis Spectroscopy

A modified facile method is presented to synthesise quantum-sized zinc oxide nanoparticles within the pores of a mesoporous silica host (SBA-11). This method eliminates the 3 h alcohol reflux and the basic solution reaction steps of zinc acetate. The mesoporous structure and the ZnO nanoparticles were analysed by X-ray diffractometry, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, nitrogen sorption analysis and UV–VIS spectroscopy. These tests confirm the synthesis of ~1 nm sized ZnO within the pores of SBA-11 and that the porous structure remained intact after ZnO synthesis.

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Green Synthesis of Zinc Oxide Nanoparticles (ZnO-NPs) Using Arthrospira platensis (Class: Cyanophyceae) and Evaluation of their Biomedical Activities

Nanomaterials ◽

10.3390/nano11010095 ◽

2021 ◽

Vol 11 (1) ◽

pp. 95

Author(s):

Ehab F. El-Belely ◽

Mohamed M. S. Farag ◽

Hanan A. Said ◽

Abeer S. Amin ◽

Ehab Azab ◽

...

Keyword(s):

Zinc Oxide ◽

Photoelectron Spectroscopy ◽

Zinc Oxide Nanoparticles ◽

Arthrospira Platensis ◽

Oxide Nanoparticles ◽

Zno Nps ◽

X Ray ◽

Vis Spectroscopy ◽

Ft Ir

In this study, zinc oxide nanoparticles (ZnO-NPs) were successfully fabricated through the harnessing of metabolites present in the cell filtrate of a newly isolated and identified microalga Arthrospira platensis (Class: Cyanophyceae). The formed ZnO-NPs were characterized by UV–Vis spectroscopy, Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Data showed the efficacy of cyanobacterial metabolites in fabricating spherical, crystallographic ZnO-NPs with a size ≈30.0 to 55.0 nm at a wavelength of 370 nm. Moreover, FT-IR analysis showed varied absorption peaks related to nanoparticle formation. XPS analysis confirms the presence of Zn(II)O at different varied bending energies. Data analyses exhibit that the activities of biosynthesized ZnO-NPs were dose-dependent. Their application as an antimicrobial agent was examined and formed clear zones, 24.1 ± 0.3, 21.1 ± 0.06, 19.1 ± 0.3, 19.9 ± 0.1, and 21.6 ± 0.6 mm, at 200 ppm against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans, respectively, and these activities were reduced as the NPs concentration decreased. The minimum inhibitory concentration (MIC) values were determined as 50 ppm for S. aureus, 25 ppm for P. aeruginosa, and 12.5 ppm for B. subtilis, E. coli, and C. albicans. More interestingly, ZnO-NPs exhibit high in vitro cytotoxic efficacy against cancerous (Caco-2) (IC50 = 9.95 ppm) as compared with normal (WI38) cell line (IC50 = 53.34 ppm).

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Enhanced Visible-Light-Driven Photocatalytic Activity of ZnAl Layered Double Hydroxide by Incorporation of Co2+

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.13.3.2168.502-511 ◽

2018 ◽

Vol 13 (3) ◽

pp. 502 ◽

Cited By ~ 1

Author(s):

Deyang Li ◽

Lihui Fan ◽

Min Qi ◽

Yanming Shen ◽

Dongbin Liu ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Layered Double Hydroxide ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Degradation Mechanism ◽

Bet Surface Area ◽

X Ray ◽

Visible Light Driven ◽

Double Hydroxide

Co-doped ZnAl layered double hydroxides (LDH) were papered by coprecipitation. The prepared samples were characterized by multiple techniques including X-ray Diffraction (XRD), Brunauer−Emmett−Teller (BET) surface area, Scanning Electronic Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and UV−Vis Diffuse-Reflectance Spectroscopy (UV−Vis DRS). The incorporation of Co2+ into the ZnAl LDH sheets as CrO6 octahedron forms a new energy level which contributes for the excitation of electrons under visible light. The doped Co2+ at a reasonable content also serves as photo-generated charges separator and improves the visible light photocatalytic activity of ZnAl LDH. A degradation mechanism based on the hydroxyl radical as the active species was proposed. Copyright © 2018 BCREC Group. All rights reservedReceived: 3rd February 2018; Revised: 8th July 2018; Accepted: 13rd July 2018How to Cite: Li, D., Fan, L., Qi, M., Shen, Y., Liu, D., Li, S. (2018). Enhanced Visible-Light-Driven Photocatalytic Activity of ZnAl Layered Double Hydroxide by Incorporation of Co2+. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 502-511 (doi:10.9767/bcrec.13.3.2168.502-511)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2168.502-511

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