Crystalline orthorhombic Ln[CO3][OH] (Ln=La, Pr, Nd, Sm, Eu, Gd) compounds hydrothermally synthesised with CO2 from air as carbonate source

2019 ◽  
Vol 74 (1) ◽  
pp. 59-70 ◽  
Author(s):  
Matthias Hämmer ◽  
Henning A. Höppe
Keyword(s):  
Rare Earth ◽  
Cetyltrimethylammonium Bromide ◽  
Hydrothermal Reaction ◽  
Nitrate Solution ◽  
Powder Xrd ◽  
Decomposition Products ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Linear Optical Properties ◽  
Carbonate Source

AbstractCrystalline orthorhombic rare earth carbonate hydroxides Ln[CO3][OH] (Ln=La, Pr, Nd, Sm, Eu, Gd) were synthesised as phase pure powders via a simple hydrothermal reaction. CO2 from air acted as natural carbonate source and cetyltrimethylammonium bromide was added as templating agent to an aqueous rare earth nitrate solution. Single-crystal X-ray structure determination was performed on La[CO3][OH] (Pnma, a=7.4106(5), b=5.0502(3), c=8.5901(6) Å, 563 independent reflections, 38 refined parameters, wR2=0.037), Pr[CO3][OH] (Pnma, a=7.2755(4), b=4.9918(3), c=8.5207(5) Å, 744 independent reflections, 38 refined parameters, wR2=0.04), Eu[CO3][OH] (Pnma, a=7.1040(4), b=4.8940(3), c=8.4577(5) Å, 1649 independent reflections, 38 refined parameters, wR2=0.05) and Gd[CO3][OH] (Pnma, a=7.069(7), b=4.874(5), c=8.464(9) Å, 431 independent reflections, 38 refined parameters, wR2=0.051). These findings are supported by powder XRD, infrared spectroscopy, UV/Vis spectroscopy and, for Pr[CO3][OH] and Eu[CO3][OH], by measurements of the non-linear optical properties. Thermal analysis could demonstrate the possible use of the Ln[CO3][OH] phases as precursors for rare earth carbonate dioxides Ln2[CO3]O2 and rare earth oxides Ln2O3. The decomposition products inherit the precursor’s morphology. The lattice parameters of Pr2[CO3]O2 were refined from high-temperature powder XRD data.

scholarly journals CHARACTERISTIC OF XONOTLITE SYNTHESIZED BY HYDROTHERMAL REACTION USING RICE HUSK ASH AND ITS APPLICATION TO ABSORB CHROME (III) SOLUTION

2021 ◽  
Vol 55 (6) ◽  
Author(s):  
Trung Kien Pham ◽  
Tran Ngo Quan
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Hydrothermal Reaction ◽  
Mekong Delta ◽  
Molar Ratio ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Xrf Scanning ◽  
Before And After ◽  
Chrome Iii

In this paper, we report on synthesizing xonotlite, calcium silicate hydrate (CSH), via a hydrothermal reaction using rice husk from the Mekong Delta, Vietnam. The rice husks were burnt at 1000 °C for 3 h. Grey rice husk ash was collected, then mixed with Ca(OH)2 at a Ca/Si molar ratio of 1 : 1. This was followed by a hydrothermal reaction at 180 °C for 24 h and 48 h to obtain the xonotlite mineral. Before and after adsorption, 3-mm xonotlite pellets were thoroughly characterized using X-ray diffractometry (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and ultraviolet-visible (UV-VIS) spectroscopy. This material has potential application in chromium(III) removal during a chrome-plating process. The adsorption efficiency of the 3-mm pellet samples reached more than 76 % after 12 h.

Study on Tungsten Oxide (WO3) Nanostructures Formation via Seeded Growth Hydrothermal Reaction

2011 ◽  
Vol 83 ◽  
pp. 204-209
Author(s):  
Rabizah Makhsin Siti ◽  
Abdul Razak Khairunisak ◽  
Zainovia Lockman
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Sodium Tungstate ◽  
Hydrothermal Reaction ◽  
Hexagonal Structure ◽  
Precursor Concentration ◽  
X Ray Diffraction ◽  
Reaction Parameters ◽  
Seeded Growth ◽  
Seed Formation ◽  
X Ray

This work describes the formation of WO3 nanostructures via seeded growth hydrothermal reaction. WO3 seed formation was first studied using thermal oxidation of W substrate from 300-500°C for 30 minutes. The optimum seeded substrates were then subjected to hydrothermal reaction at 80°C by varying precursor concentration and pH of the solution. Optimum oxidation temperature to produce WO3 seeds was at 400°C for 30 minutes. Below 400°C, no seed was formed while above that temperature the seeds became too compact and less uniform. The optimum hydrothermal reaction parameters were obtained after 24 hrs reaction time, concentration ratio of sodium tungstate dehydrate to cetyltrimethylammonium bromide (CTAB) of 6:1 and at pH 2. By lowering the pH and increasing the precursor concentration, the growth of WO3 nanostructures was enhanced. X-ray diffraction analysis showed that WO3 nanostructures formed were of hexagonal structure.

Growth of CuS Nanostructures by Hydrothermal Route and Its Optical Properties

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Murugan Saranya ◽  
Chella Santhosh ◽  
Rajendran Ramachandran ◽  
Andrews Nirmala Grace
Keyword(s):  
Optical Properties ◽  
Cetyltrimethylammonium Bromide ◽  
Copper Nitrate ◽  
X Ray Diffraction ◽  
Sodium Thiosulphate ◽  
Hydrothermal Route ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

CuS nanostructures have been successfully synthesized by hydrothermal route using copper nitrate and sodium thiosulphate as copper and sulfur precursors. Investigations were done to probe the effect of cationic surfactant, namely, Cetyltrimethylammonium bromide (CTAB) on the morphology of the products. A further study has been done to know the effect of reaction time on the morphology of CuS nanostructures. The FE-SEM results showed that the CuS products synthesized in CTAB were hexagonal plates and the samples prepared without CTAB were nanoplate like morphology of sizes about 40–80 nm. Presence of nanoplate-like structure of size about 40–80 nm was observed for the sample without CTAB. The synthesized CuS nanostructures were characterized by X-ray diffraction (XRD), FE-SEM, DRS-UV-Vis spectroscopy, and FT-IR spectroscopy. A possible growth mechanism has been elucidated for the growth of CuS nanostructures.

scholarly journals Investigating the Possibility of Green Synthesis of Silver Nanoparticles Using Vaccinium arctostaphlyos Extract and Evaluating Its Antibacterial Properties

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Sedighe Khodadadi ◽  
Nafiseh Mahdinezhad ◽  
Bahman Fazeli-Nasab ◽  
Mohammad Javad Heidari ◽  
Baratali Fakheri ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Ftir Spectroscopy ◽  
Aqueous Extract ◽  
Nitrate Solution ◽  
Antibacterial Properties ◽  
Silver Nitrate Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy

Objective. Vaccinium genus plants have medicinal value, of which Vaccinium arctostaphylos (Caucasian whortleberry or Qare-Qat in the local language) is the only available species in Iran. Public tendency to use herbal remedies and natural products such as synthesized nanoparticles is increasing due to the proof of the destructive side effects of chemical drugs. Nanosilver products have been effective against more than 650 microbe types. This study was aimed at assessing the possibility of green synthesis of silver nanoparticles using Vaccinium arctostaphylos aqueous extract and at evaluating its antibacterial properties, as well. Materials and Methods. In order to synthesize silver nanoparticles, different volumes of Vaccinium arctostaphylos aqueous extract (3, 5, 10, 15, and 30 ml) were assessed with different silver nitrate solution concentrations (0.5, 1, 3, 5, and 10 mM) and different reaction time durations (1, 3, 5, 10, and 20 minutes) at room temperature using a rotary shaker with a speed of 150 rpm. Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were carried out. The antibacterial activity of the aqueous extract and the synthesized nanoparticles was evaluated, as well. Results. Silver nanoparticle formation process was confirmed with XRD analysis, transmission electron microscopy (TEM), and FTIR spectroscopy. The UV-Vis spectroscopy of silver colloidal nanoparticles showed a surface plasmon resonance peak at 443 nm under optimal conditions (3 ml aqueous extract volume, 1 mM silver nitrate solution concentration, and 3 min reaction time under sunlight exposure). The reduction of silver ions to silver nanoparticles in solution was confirmed, as well. Based on X-ray diffraction analysis, the size of silver nanoparticles was in the range of 7-16 nm. TEM images showed an even distribution of silver nanoparticles, with a spherical shape. FTIR spectroscopy demonstrated the presence of different functional groups of oxygenated compounds such as carboxyl, hydroxyl, and nitrogenous groups. The antibacterial properties of the synthesized nanoparticles were confirmed. Conclusion. The synthesized nanoparticles showed more antibacterial properties against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than gram-negative ones (Escherichia coli and Salmonella enteritidis).

scholarly journals A green deposition method of silver nanoparticles on textiles and their antifungal activity

2019 ◽  
Vol 10 (1) ◽  
pp. 4902-4907 ◽  
Keyword(s):  
Silver Nanoparticles ◽  
Antifungal Activity ◽  
Nitrate Solution ◽  
Chemical Compounds ◽  
Silver Nitrate Solution ◽  
Inhibition Zone ◽  
Green Method ◽  
Mikania Micrantha ◽  
X Ray ◽  
Vis Spectroscopy

This study aims to propose a new green method for the deposition of silver nanoparticles (AgNPs) on textiles without the use of chemical compounds as binders. The deposition of AgNPs on textiles was achieved by immersing textiles in silver nitrate solution before adding with a natural reducing agent obtained from the extraction of Mikania micrantha. Plasmonic properties of the synthesized AgNPs were characterized using Ultraviolet-visible (UV–vis) spectroscopy and surface morphology of textiles was identified using the field-emission scanning electron microscopy (FESEM). In addition, energy-dispersive X-ray spectroscopy was also employed for the characterization. Inhibition zone measurement was performed for evaluating the antifungal capability of textiles attached with AgNPs. This study showed that the attachment of AgNPs to several textile types (cotton, cotton-polyester, silk, and fiber) without the use of binders or other chemical compounds had been successfully achieved. Moreover, all textiles attached with AgNP exhibited effective antifungal activity.

Nanostructures of the Product Sequence in the Decomposition of Mixed Rare Earth Hydroxycarbonate Colloidal Particles

1992 ◽  
Vol 272 ◽  
Author(s):  
Z. C. kang ◽  
M. J. Mckelvy ◽  
L. Eyring
Keyword(s):  
Thermal Analysis ◽  
Electron Beam ◽  
Rare Earth ◽  
Colloidal Particles ◽  
X Ray Diffraction ◽  
Decomposition Products ◽  
X Ray ◽  
Colloidal Spheres ◽  
Diffraction Patterns ◽  
Product Sequence

ABSTRACTThe decomposition of colloidal spheres of mixed rare earth hydroxycarbonate to the oxide has been studied by three methods. a) The spheres are treated in a thermal analysis apparatus up to 1100°C and afterward successive reruns were made and specimens cooled rapidly at temperatures where intermediate or final products are formed. X-ray diffraction patterns and HREM studies were made of each sample thus produced. b) The spheres were heated to 450°C in the specimen chamber of a mass spectrometer and the gaseous decomposition products were monitored continuously. c) The colloidal spheres were introduced into the electron microscope and the decomposition followed at high resolution as evolution to the oxide was induced by the electron beam. The results are compared and contrasted.

Synthesis of Fe-Co Nanobars Using Sodium Sulfite Assisted Polyol Process and their Structural and Magnetic Studies

2011 ◽  
Vol 15 ◽  
pp. 21-28 ◽  
Author(s):  
G. Suresh ◽  
P. Saravanan ◽  
D. Rajan Babu
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Sodium Sulfite ◽  
Polyol Process ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Magnetic Studies ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Co Nanoparticles

We report the synthesis of soft magnetic Fe-Co nanobars by an improved polyol process using cetyltrimethylammonium bromide (CTAB) as stabilizer. The synthesized samples were studied by using Transmission Electron Microscopy. The Fe-Co nanoparticles were characterized by X-ray diffraction, UV-Vis spectroscopy, Fourier transform infrared spectroscopy and Vibrating Sample Magnetometer. The Fe-Co nanobars showed prominent UV-VIS absorption at 371 nm. This report discusses the effect of sodium sulfite and CTAB on the synthesis of Fe-Co nanoparticles.

New Structure of CTAB Templated Silica Films as revealed by GISAXS coupled to HRTEM

2000 ◽  
Vol 628 ◽  
Author(s):  
Sophie Besson ◽  
Catherine Jacquiod ◽  
Thierry Gacoin ◽  
André Naudon ◽  
Christian Ricolleau ◽  
...  
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Grazing Incidence ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Hexagonal Arrangement ◽  
Spherical Micelles

ABSTRACTA microstructural study on surfactant templated silica films is performed by coupling traditional X-Ray Diffraction (XRD) and Transmission Electronic Microscopy (TEM) to Grazing Incidence Small Angle X-Ray Scattering (GISAXS). By this method it is shown that spin-coating of silicate solutions with cationic surfactant cetyltrimethylammonium bromide (CTAB) as a templating agent provides 3D hexagonal structure (space group P63/mmc) that is no longer compatible with the often described hexagonal arrangement of tubular micelles but rather with an hexagonal arrangement of spherical micelles. The extent of the hexagonal ordering and the texture can be optimized in films by varying the composition of the solution.

Exploring the characteristics of the nickel oxide nanoparticles via Sol - gel method

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Jothi M ◽  
Sowmiya K
Keyword(s):  
Nickel Oxide ◽  
Ph Value ◽  
Lattice Structure ◽  
Sol Gel ◽  
Systematic Change ◽  
Average Crystalline Size ◽  
Nio Nanoparticles ◽  
Nickel Oxide Nanoparticles ◽  
X Ray ◽  
Vis Spectroscopy

Nickel Oxide (NiO) is an important transition metal oxide with cubic lattice structure. NiO is thermally stable that is suitable for tremendous applications in the field of optic, ceramic,glass, electro-chromic coatings, plastics, textiles, nanowires, nanofibers, electronics,energy technology, bio-medicine, magnetism and so on. In this present study, NiO nanoparticles were successfully synthesized by sol-gel technique. Nano-sols were prepared by dissolving Nickel-Chloride [NiCl2.6H2O] in NaOH solvent and were converted into nano structured gel on precipitation. A systematic change in preparation parameters like calcination temperature, time, pH value has been noticed in order to predict the influence on crystallite size. Then the prepared samples were characterized by the X-ray Diffraction Spectroscopic (XRD), UV-VIS Spectroscopy, Fourier Transform Infra-Red Spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscopy (SEM) and Particle Size Analyzer (PSA). From XRD, the average crystalline-size has been calculated by Debye-Scherrer Equation and it was found to be 12.17 nm and the band gap energy of Nickel oxide (NiO) from UV studies reveals around 3.85 eV. Further, EDX and FTIR studies, confirm the presences of NiO nanoparticles. The SEM study exhibits the spherical like morphology of Nickel oxide (NiO). Further from PSA, the mean value of NiO nanoparticles has been determined.

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