Preparation and Characterization of Nanocrystalline Ce-Containing Layered Double Hydroxides

Ce-containing Layered Double Hydroxides (Ce-LDHs) were prepared by conventional and microwave-assisted crystallization method, which were denoted as Ce-LDHs-A and Ce-LDHs-B, respectively. The dispersibility of Ce-LDHs-B is much better than that of Ce-LDHs-A; the particles of Ce-LDHs-B with particle size ranging from 20 to 70 nm are smaller than that of Ce-LDHs-A with sizes around 50-300 nm. The effect of the cerium to aluminum molar ratios, microwave crystallization time and reaction temperature on the structure of Ce-LDHs was also investigated. The results show the excessive Ce into LDHs causes distortion of the samdwich, the damage of the LDHs structure becomes more and more serious with increasing the proportion of Ce/Al. The structure of Ce-LDHs becomes more and more perfect with the increasing of the microwave crystallization time and reaction temperature.

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Structural Characterization of Microwave-Assisted Solution-Synthesized Strontium-Substituted Hydroxyapatite

NANO ◽

10.1142/s1793292016501150 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1650115

Author(s):

Jianguo Liao ◽

Yanqun Li ◽

Xiali Guan ◽

Jingxian Liu ◽

Yongxiang Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Hexagonal Structure ◽

Hydroxyapatite Nanoparticles ◽

Solution Synthesis ◽

X Ray ◽

Molar Ratios ◽

Microwave Assisted ◽

Transmission Electron

Hydroxyapatite and strontium-substituted hydroxyapatite nanoparticles (n-HA and Sr-HA) were prepared by microwave-assisted solution synthesis with aqueous solutions of various Sr/(Sr[Formula: see text]Ca) molar ratios ranging from 0% to 15%. The structural properties of the hydroxyapatite powders were investigated by X-ray powder diffraction, Fourier transform infrared spectroscopy and Raman spectra, field emission scanning electron microscopy coupled with energy dispersive X-ray spectrometry and transmission electron microscopy. The results confirmed that strontium ions had been incorporated into the hydroxyapatite lattice. The synthetic n-HA and Sr-HA nanocrystalline consisted of hydroxyapatite crystalline phase with hexagonal structure, and the particle size was 30–40 × 60–70[Formula: see text]nm and 40–50 × 70–80[Formula: see text]nm, respectively. The calcined HA particle size ranged from about 120[Formula: see text]nm to 150[Formula: see text]nm, the calcined Sr-HA products were composed of spherical aggregates with a size of about 70–100[Formula: see text]nm. The incorporation of Sr ions lead to the formation of vacancies in the crystal structure of the HA. The results indicated that the strontium substitution did not change the crystal structures. More Sr resulted in less calcined crystallites and formed agglomerates owing to the size effect.

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Comparison between Conventional and Microwave-Assisted Synthesis of Cu-Containing Layered Double Hydroxides

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.554-556.532 ◽

2012 ◽

Vol 554-556 ◽

pp. 532-535

Author(s):

Chun Xia Chen ◽

Kun Zhang ◽

Bin Li

Keyword(s):

Catalytic Activity ◽

Layered Double Hydroxides ◽

Raw Material ◽

Microwave Assisted Synthesis ◽

Phenol Hydroxylation ◽

Particle Size Range ◽

Microwave Assisted ◽

Material Utilization ◽

Double Hydroxides ◽

Better Than

Cu-containing Layered Double Hydroxides (Cu-LDHs) prepared in a microwave field (Cu-LDHs-b) differs drastically according to the appearance, chemical component and the catalytic activity when compared with conventionally prepared sample (Cu-LDHs-a). From the TEM images, it is obvious that the particle size range of Cu-LDHs-b with 30～90 nm is narrower than that of Cu-LDHs-a with 30～120 nm, and the dispersibility of Cu-LDHs-b is better than that of Cu-LDHs-a. ICP-AES characterization shows that raw material utilization ratio of Cu-LDHs-b is higher than that of Cu-LDHs-a. Furthermore, Cu-LDHs-b exhibites higher catalytic activity than Cu-LDHs-a in the phenol hydroxylation with H2O2. Therefore, the microwave-assisted synthesis is an ideal method for synthesis of nano-Cu-LDHs.

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Synthesis and characterization of Layered Double Hydroxides aimed at encapsulation of sodium diclofenac: Theoretical and experimental study

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.116677 ◽

2021 ◽

pp. 116677

Author(s):

Samra Amamra ◽

Hayet Elkolli ◽

Yacine Benguerba ◽

Alessandro Erto ◽

Marco Balsamo ◽

...

Keyword(s):

Experimental Study ◽

Layered Double Hydroxides ◽

Synthesis And Characterization ◽

Sodium Diclofenac ◽

Double Hydroxides

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Co-Cr bimetallic oxide derived from layered double hydroxides with high catalytic performance for chlorinated aromatics oxidation

Catalysis Science & Technology ◽

10.1039/d1cy00791b ◽

2021 ◽

Author(s):

Wei Deng ◽

Biao Gao ◽

Ziye Jia ◽

Dongqi Liu ◽

Limin Guo

Keyword(s):

Physicochemical Properties ◽

Layered Double Hydroxides ◽

Catalytic Performance ◽

Chlorinated Aromatics ◽

Molar Ratios ◽

Double Hydroxides

Co-Cr bimetallic oxide with different Co/Cr molar ratios were prepared through a layered double hydroxides (LDHs) derived method. Their physicochemical properties together with catalytic performance for chlorinated aromatics (1, 2-dichlorobenzene...

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LAYERED DOUBLE HYDROXIDES: NANOMATERIALS FOR APPLICATIONS IN AGRICULTURE

Revista Brasileira de Ciência do Solo ◽

10.1590/01000683rbcs2015081 ◽

2015 ◽

Vol 39 (1) ◽

pp. 1-13 ◽

Cited By ~ 39

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.

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