scholarly journals Oxidation of Cysteinate Anions Immobilized in the Interlamellar Space of CaAl-Layered Double Hydroxide

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1202
Author(s):  
Zita Timár ◽  
Truong Ngoc Hung ◽  
Cora Pravda ◽  
Zoltán Kónya ◽  
Ákos Kukovecz ◽  
...  
Keyword(s):  
Layered Double Hydroxide ◽  
Room Temperature ◽  
Precipitation Method ◽  
Confined Space ◽  
Oxidation Reactions ◽  
Sulfenic Acid ◽  
X Ray ◽  
Mild Conditions ◽  
Co Precipitation ◽  
Double Hydroxide

L-Cysteinate-intercalated CaAl-layered double hydroxide (LDH) was prepared by the co-precipitation method producing highly crystalline hydrocalumite phase with a well-pillared interlayer gallery. The obtained materials were characterized by X-ray diffractometry, IR as well as Raman spectroscopies. By performing interlamellar oxidation reactions with peracetic acid as oxidant, oxidation of cysteinate to cystinate in aqueous and cysteinate sulfenic acid in acetonic suspensions occurred. The oxidations could be performed under mild conditions, at room temperature, under neutral pH and in air. It has been shown that the transformation pathways are due to the presence of the layered structure, that is, the confined space of the LDH behaved as molecular reactor.

scholarly journals Cephradine Intercalated Mg-Al Layered Double Hydroxide

2016 ◽  
Vol 69 ◽  
pp. 1-9
Author(s):  
Md Ashaduzzaman ◽  
Nashid Kaisher Riyadh ◽  
Nusrat Mustary ◽  
Sayed Md Shamsuddin
Keyword(s):  
Layered Double Hydroxide ◽  
Homogeneous Solution ◽  
Functional Materials ◽  
Bioactive Molecules ◽  
Biomedical Science ◽  
Precipitation Method ◽  
X Ray ◽  
Before And After ◽  
Co Precipitation ◽  
Double Hydroxide

Engineered advanced functional materials are promising candidates for biotechnology and biomedical science. Mg-Al layered double hydroxide (LDH), anionic or hydrotalcite-like clays consist of positively charged layers and exchangeable anions along with water molecules in the interlayer space were synthesized from homogeneous solution of MgCl2and AlCl3by urea induced co-precipitation method. A pharmaceutically important drug, cephradine was intercalated with synthesized LDH in alkali media (pH 10) by in-situ technique. Characterizations of the products were carried out using Attenuated Total Reflectance Infra-red (ATR-IR), Energy Dispersive X-ray (EDX) and X-ray Diffraction (XRD) spectroscopy. Scanning electron morphological images envisaged a distinct crystalline and amorphous phases of Mg-Al LDH before and after modification with cephradine. Intercalation of bioactive molecules with LDH would enhance their stability providing sustained release behavior in physiological environment.

An elegant synthesis of chitosan grafted hydrotalcite nano-bio composite material and its effective catalysis for solvent-free synthesis of jasminaldehyde

RSC Advances ◽  
2015 ◽  
Vol 5 (115) ◽  
pp. 94562-94570 ◽  
Author(s):  
Jacky H. Adwani ◽  
Noor-ul H. Khan ◽  
Ram S. Shukla
Keyword(s):  
Composite Material ◽  
Layered Double Hydroxide ◽  
Solvent Free ◽  
Precipitation Method ◽  
Co Precipitation ◽  
Double Hydroxide ◽  
Solvent Free Synthesis

A novel nano-bio composite of chitosan and a layered double hydroxide elegantly synthesized by a co-precipitation method had effectively and selectively catalysed the jasminaldehyde synthesis.

Preparation and Electrochemical Performance of Mn3O4/GR Composites Electrode Material in Supercapacitors

2019 ◽  
Vol 807 ◽  
pp. 50-56
Author(s):  
Yun Long Zhou ◽  
Zhi Biao Hu ◽  
Li Mei Wu ◽  
Jiao Hao Wu
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Precipitation Method ◽  
Electrochemical Performances ◽  
Manganese Sulfate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Precipitation ◽  
A Current ◽  
Discharge Test

Using hydrated manganese sulfate and general type graphene (GR) as raw materials, Mn3O4/GR composite has been successfully prepared by the liquid phase chemical co-precipitation method at room temperature. X-ray diffraction (XRD) was used to investigate the phase structure of Mn3O4powder and Mn3O4/GR composite; The electrochemical performances of the samples were elucidated by cyclic voltammetry and galvanostatic charge-discharge test in 0.5 mol/L Na2SO4electrolyte. The results show that the Mn3O4/GR composite possesses graphene phase and good reversibility; the composite also displays a specific capacitance of 318.8 F/g at a current density of 1 A/g.

scholarly journals Structural Stability of Ni/Al Layered Double Hydroxide Supported on Graphite and Biochar Toward Adorption of Congo Red

2021 ◽  
Vol 6 (2) ◽  
pp. 85-95
Author(s):  
Patimah Mega Syah Bahar Nur Siregar ◽  
Neza Rahayu Palapa ◽  
Alfan Wijaya ◽  
Erni Salasia Fitri ◽  
Aldes Lesbani
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Layered Double Hydroxide ◽  
Congo Red ◽  
High Performance ◽  
Precipitation Method ◽  
First Order ◽  
Xrd Diffraction ◽  
Co Precipitation ◽  
Double Hydroxide

In this research, Ni/Al layered double hydroxide (LDH) was modified by using co-precipitation method to generate Ni/Al-graphite (Ni/Al-GF) and Ni/Al-biochar (Ni/Al-BC). The adsorbents were applied to remove Congo Red from aqueous solution. The obtained samples were characterized by using XRD, FTIR, BET and TG-DTA. The XRD diffraction pattern of Ni/Al LDH, Ni/Al-GF, and Ni/Al-BC presented the formation of composite with decreasing crystallinity. The surface area modified LDHs was higher than the pristine materials, which was obtained 15.106 m2/g, 21.595 m2/g and 438.942 m2/g for Ni/Al-LDH, Ni/Al-GF, Ni/Al-BC respectively. The adsorption of Congo Red on the materials was tested at diferent parameters and the results exhibited that Congo Red adsorption on LDHs were pseudo-first-order (PFO) kinetic, spontaneous, endothermic and followed Langmuir model. The adsorbents removed Congo Red by high performance stability with adsorption capacity was 116.297 mg/g for Ni/Al-GF and 312.500 mg/g for Ni/Al-BC. These adsorption capacity was higher than the pristine LDH (61.728 mg/g). The regeneration process which carried out for five cycles showed that Ni/Al-GF and Ni/Al-BC have stable structures as reuse adsorbents for Congo Red from aqueous solution.

scholarly journals Photodecolourization of congo red dye in presence of Ni3+ layered double hydroxide

2021 ◽  
Vol 30 ◽  
pp. 02010
Author(s):  
Irina Ryltsova ◽  
Evgenia Tarasenko ◽  
Olga Lebedeva
Keyword(s):  
Layered Double Hydroxide ◽  
Congo Red ◽  
Uv Light ◽  
Order Kinetic ◽  
X Ray ◽  
Congo Red Dye ◽  
Order Kinetic Model ◽  
Co Precipitation ◽  
Red Dye ◽  
Double Hydroxide

Layered double hydroxide containing Ni3+ (Mg/AlNi-LDH) was successfully synthesized by co-precipitation in an oxidizing media. The resulted product was characterized using X-ray diffraction, wavelength dispersive X-ray fluorescence spectrometry. The activity of Mg/AlNi-LDH in the process of photodegradation of Congo red dye using UV light irradiation was evaluated. The initial rate of photodegradation of the dye in the presence of LDH is 1.6 times higher than that of UV irradiated solution. The kinetic data obtained for photodegradation process can be adequately described by pseudo-first-order kinetic model. The presence of Mg/AlNi – LDH leads to increased photodegradation yield compared to destruction only by UV irradiation.

Fabrication of TiO2@ZnAl-layered double hydroxide based anode material for dye-sensitized solar cell

RSC Advances ◽  
2016 ◽  
Vol 6 (13) ◽  
pp. 10912-10918 ◽  
Author(s):  
Leila Jafari Foruzin ◽  
Zolfaghar Rezvani ◽  
Kamellia Nejati
Keyword(s):  
Solar Cell ◽  
Anode Material ◽  
Layered Double Hydroxide ◽  
Dye Sensitized Solar Cell ◽  
Precipitation Method ◽  
Dye Sensitized ◽  
Co Precipitation ◽  
Double Hydroxide

A TiO2@ZnAl-layered double hydroxide nanocomposite was prepared by the co-precipitation method; then, the product was calcined in order to obtain the TiO2@MMO nanocomposite, and use as anode material in dye-sensitized solar cell (DSSC).

Effect of PEG on Structural and Magnetic Properties of Mn Doped ZnO Nanocrystals

2013 ◽  
Vol 678 ◽  
pp. 234-238 ◽  
Author(s):  
Vishwanath D. Mote ◽  
Babasaheb N. Dole
Keyword(s):  
Room Temperature ◽  
Magnetic Hysteresis ◽  
Lattice Parameters ◽  
Precipitation Method ◽  
Average Crystalline Size ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Doped Zno ◽  
Co Precipitation ◽  
Mn Doped

Nanosized Mn doped ZnO samples were synthesized by co-precipitation method using Polyethylene glycol (PEG) as a capping agent. X- ray diffraction patterns confirm that the pure and Mn doped ZnO nanocrystals have wurtzite structure without any seconadary phases. Lattice parameters of pure and Mn doped ZnO nanocrystals increase slightly with increasing Mn concentration. The average crystalline size of pure and Mn doped ZnO nanocrystals are in the range of 14-18 nm. The X-ray density for pure and Mn doped ZnO sample is calculated using lattice parameters. It is found that almost static for Mn doped ZnO samples. In the Zn1-xMnx samples, room temperature magnetic hysteresis is observed and the saturation magnetization increases with increasing Mn content. However, these samples show room temperature ferromagnetic in nature. Result of the present investigation compared without PEG.

scholarly journals Removal of Lead from Aqueous Solution by Adsorption using Magnesium Aluminium Hydrogenphosphate Layered Double Hydroxides

2014 ◽  
Vol 8 (1) ◽  
Author(s):  
Zaini Hamzah ◽  
Mohd Najif Ab Rahman ◽  
Yamin Yasin ◽  
Siti Mariam Sumari ◽  
Ahmad Saat
Keyword(s):  
Aqueous Solution ◽  
Layered Double Hydroxide ◽  
Molar Ratio ◽  
Maximum Adsorption Capacity ◽  
Lead Removal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Precipitation ◽  
Double Hydroxide ◽  
Double Hydroxides

Layered double hydroxide with molar ratio of 4 (MAN 4) was synthesized by co-precipitation and followed by hydrothermal method. The compound was then later going through ion exchange with K2HPO4 for 48 hours to produce MgAlHPO4 (MAHP 4). The solid produced were characterized using X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). Adsorption of lead solution by MAHP 4 was carried out using batch experiment by mixing the lead solution and the solid of layered double hydroxide. The effects of various parameters such as contact time, pH, adsorbent dosage and initial concentration were investigated. The optimum pH for lead removal was found to be at pH of 5 and the optimum time of lead removal was found at 2 hours. The isotherm data was analysed using Langmuir and the correlation coefficient of 0.998 was obtained. The maximum adsorption capacity, Qo (mg/g) of 500 mg/g was also recorded from the Langmuir isotherm. The remaining lead solution was determined by using EDXRF (Energy Dispersive X-Ray Fluorescence spectrometry) model MiniPal 4 (PAN analytical). The results in this study indicate that MAHP 4 was an interesting adsorbent for removing lead from aqueous solution.

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

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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