scholarly journals Synthesis and Characterization of Layered Double Hydroxides as Materials for Electrocatalytic Applications

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 725
Author(s):  
Domenica Tonelli ◽  
Isacco Gualandi ◽  
Elisa Musella ◽  
Erika Scavetta
Keyword(s):  
Layered Double Hydroxides ◽  
Metal Centers ◽  
Anionic Clays ◽  
Direct Modification ◽  
Reversible Redox ◽  
Wide Range ◽  
Charge Transfer Reactions ◽  
Double Hydroxides

Layered double hydroxides (LDHs) are anionic clays which have found applications in a wide range of fields, including electrochemistry. In such a case, to display good performances they should possess electrical conductivity which can be ensured by the presence of metals able to give reversible redox reactions in a proper potential window. The metal centers can act as redox mediators to catalyze reactions for which the required overpotential is too high, and this is a key aspect for the development of processes and devices where the control of charge transfer reactions plays an important role. In order to act as redox mediator, a material can be present in solution or supported on a conductive support. The most commonly used methods to synthesize LDHs, referring both to bulk synthesis and in situ growth methods, which allow for the direct modification of conductive supports, are here summarized. In addition, the most widely used techniques to characterize the LDHs structure and morphology are also reported, since their electrochemical performance is strictly related to these features. Finally, some electrocatalytic applications of LDHs, when synthesized as nanomaterials, are discussed considering those related to sensing, oxygen evolution reaction, and other energy issues.

scholarly journals Antibiotic Encapsulated Nanomaterials with Application in Medical Area

2018 ◽  
Vol 55 (4) ◽  
pp. 552-554
Author(s):  
Alina Costina Luca ◽  
Letitia Doina Duceac ◽  
Geta Mitrea ◽  
Madalina Irina Ciuhodaru ◽  
Daniela Luminita Ichim ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Chemical Properties ◽  
Morphological Characterization ◽  
Drug Controlled Release ◽  
Anionic Clays ◽  
Amoxicillin Clavulanic Acid ◽  
Double Hydroxides ◽  
Physical And Chemical ◽  
And Chemical Properties

Novel materials belonging to the class of anionic clays are synthesized by investigating their properties at nano scale. Thus, hydrotalcites or layered double hydroxides (LDHs) were used as drug delivery carriers in order to prevent or to treat infections produced by some pathogen agents. Their physical and chemical properties allow them to include different molecules in the interlayer space and then to ensure their transport to the target. The current work reveals the obtaining of nanohybrid compounds type amoxicillin/clavulanic acid-layered double hydroxides (Amox/CA-LDHs) followed by structural and morphological characterization of these nanostructures for future applications as drug controlled release systems. IR spectroscopy and Scanning Electron Microscopy pointed out LDHs ability to incorporate the medicines without modification of therapeutic activity.

Antibiotic-anionic Clay Matrix Used for Drug Controlled Release

2018 ◽  
Vol 69 (2) ◽  
pp. 321-323
Author(s):  
Georgeta Zegan ◽  
Elena Mihaela Carausu ◽  
Loredana Golovcencu ◽  
Alina Sodor Botezatu ◽  
Eduard Radu Cernei ◽  
...  
Keyword(s):  
Controlled Release ◽  
Layered Double Hydroxides ◽  
Bioactive Molecules ◽  
Drug Controlled Release ◽  
Anionic Clays ◽  
Anionic Clay ◽  
Toxicological Studies ◽  
High Efficient ◽  
Clay Matrix ◽  
Double Hydroxides

Anionic clay matrix acting as drug controlled release system have shown in last years a great potential for delivery of bioactive molecules and chemical therapeutics. This organic-inorganic nanohybrid system is high efficient offering an excellent protection of intercalated compounds from degradation. Compared to other nanoparticles used in medical area, anionic clays type layered double hydroxides have found to be biocompatible according to toxicological studies. Ampicillin containing MgAlLDHs and ZnAlLDH samples have been prepared following two routes: anion-exchange procedure and reconstruction from calcined layered double hydroxides. Solid samples have been characterized by FTIR and SEM-EDX highlighting the alteration of pristine LDHs structure when the antibiotic is introduced in the interlayer gallery.

scholarly journals LAYERED DOUBLE HYDROXIDES: NANOMATERIALS FOR APPLICATIONS IN AGRICULTURE

2015 ◽  
Vol 39 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Luíz Paulo Figueredo Benício ◽  
Rejane Alvarenga Silva ◽  
Júnia Aparecida Lopes ◽  
Denise Eulálio ◽  
Rodrigo Morais Menezes dos Santos ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Layered Double Hydroxides ◽  
Slow Release ◽  
Structural Characteristics ◽  
Synthesis Methods ◽  
Double Hydroxides ◽  
Near Future

The current research aims to introduce Layered Double Hydroxides (LDH) as nanomaterials to be used in agriculture, with particular reference to its use as storage and slow release matrix of nutrients and agrochemicals for plant growing. Structural characteristics, main properties, synthesis methods and characterization of LDH were covered in this study. Moreover, some literature data have been reported to demonstrate their potential for storage and slow release of nitrate, phosphate, agrochemicals, besides as being used as adsorbent for the wastewater treatment. This research aims to expand, in near future, the investigation field on these materials, with application in agriculture, increasing the interface between chemistry and agronomy.

Structural characterization of azoic dye hosted layered double hydroxides

2009 ◽  
Vol 224 (5-6) ◽  
Author(s):  
Sujata Mandal ◽  
Dan A. Lerner ◽  
Nathalie Marcotte ◽  
Didier Tichit
Keyword(s):  
Structural Characterization ◽  
Layered Double Hydroxides ◽  
Double Hydroxides

scholarly journals X-Ray Fluorescence Analysis of a Gold Ibex and other Artifacts from Akrotiri

2019 ◽  
Vol 11 ◽  
Author(s):  
A. G. Karydas ◽  
T. Pantazis ◽  
C. Doumas ◽  
A. Vlachopoulos ◽  
P. Nomikos ◽  
...  
Keyword(s):  
Bulk Composition ◽  
Fluorescence Analysis ◽  
Wall Painting ◽  
Inorganic Elements ◽  
X Ray ◽  
Wide Range ◽  
Soldering Technology ◽  
Excavation Area

In-situ X-ray fluorescence analysis (XRF) of ancient artifacts from the excavation area was performed using a novel X-ray instrumentation, composed of a portable silicon PIN thermoelectrically cooled X-ray detector, a miniature X-ray source, and portable data acquisition devices. The main objective of the analyses in Akrotiri was to explore the potential of the technique to provide answers to a wide range of archaeometric questions regarding the bulk composition of metal alloys, especially of gold, the characterization of corrosion products in bronze artifacts, identification of inorganic elements which are fingerprints of the minerals used in wall-painting pigments, and of the painting materials and techniques used for the decoration of clay vase surfaces. Among the analysed artifacts are a unique gold ibex, a bronze dagger and blade, various pigments from the wall paintings of room 3 in Xeste 3, decoration pigments from rosettes of faience, a bichrome jug, and other clay vases. The results of the in-situ XRF survey, primarily those of the bulk composition and soldering technology of the gold ibex, are discussed and compared with literature.

Synthesis of Li/Al layered double hydroxide-guest composites under mild acid conditions

Clay Minerals ◽  
2004 ◽  
Vol 39 (2) ◽  
pp. 115-121 ◽  
Author(s):  
Deng-Shiu Yang ◽  
Ming-Kuang Wang ◽  
Shan-Li Wang
Keyword(s):  
Layered Double Hydroxide ◽  
Layered Double Hydroxides ◽  
Starting Material ◽  
Anionic Clays ◽  
Step Procedure ◽  
Alkaline Conditions ◽  
Double Hydroxide ◽  
Double Hydroxides ◽  
Mild Acid ◽  
Positively Charged

AbstractLayered double hydroxides (LDHs) are known as ‘anionic clays’. They comprise a class of material with positively charged octahedral double hydroxyl layers and exchangeable anions. The Li/Al LDH term includes a group of LDHs with Li/Al octahedral double hydroxyl layers. We have demonstrated a modifed method, using Li/Al LDH-OH (OH− as interlayer anions) as the starting material, for preparing Li/Al LDH-X (X represents interlayer anions, including dioctyl sulphosuccinate (DOSS), dodecyl sulphate (DDS), mercaptoacetate (MA), EDTA, Tiron and dichromate) under mild acid conditions (pH in the range 4 to 5). However, in the case of acidsensitive anions, Fe(CN)64−, Li/Al LDH-Fe(CN)64− can be prepared by a two-step procedure using Li/Al LDH-DOSS or similar compounds as intermediates to react with acid-sensitive anions under mild alkaline conditions (pH ≈ 9).

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