The Effects of Water Removal Process on the Properties of Magnesium Aluminate Spinel Nanopowders Synthesized by Co-Precipitation Method

2015 ◽  
Vol 659 ◽  
pp. 159-163
Author(s):  
Sarut Teerasoradech ◽  
Karn Serivalsatit
Keyword(s):  
Electron Microscopy ◽  
Precipitation Method ◽  
Magnesium Aluminate ◽  
Water Removal ◽  
Magnesium Aluminate Spinel ◽  
Drying Process ◽  
Simple Method ◽  
Removal Process ◽  
Conventional Drying ◽  
Co Precipitation

Magnesium aluminate spinel (MgAl2O4) or spinel ceramics have been widely used in engineering fields due to its attractive properties, such as high mechanical strength, good optical properties, and high refractoriness. Precipitation is one of the most common techniques for preparing spinel nanopowders because it offers many advantages including low cost, simple method, and ease of mass production. However, severe agglomeration usually takes place during water removal process, i.e. washing and drying. These hard agglomerates deteriorate sinterability of nanopowders. In this study, spinel nanopowders were prepared by co-precipitation method. The remaining water in the precipitated precursor was removed by washing the precipitated precursor with organic solvents, i.e. ethanol and acetone-toluene-acetone. Conventional drying process was also performed for comparison. The characteristics of the obtained spinel nanopowders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and dynamic light scattering (DLS) method. The results showed that the water removal process did not have any significant effects on phases of the dried precursors and the calcined powders. However, washing the precipitate precursor with organic solvent is the most effective process to prepare spinel nanopowders with low degree of agglomeration. Whereas, removing water by conventional drying process led to the formation of hard agglomerates. Furthermore, the effects of water removal process on sinterability of the spinel nanopowders were also reported.

scholarly journals Synthesis of Magnesium Aluminate Spinel Powder from the Purified Sodium Hydroxide Leaching Solution of Black Dross

Processes ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 741 ◽  
Author(s):  
Nguyen ◽  
Lee
Keyword(s):  
Sodium Hydroxide ◽  
Ball Milling ◽  
Calcination Temperature ◽  
Precipitation Method ◽  
Magnesium Aluminate ◽  
Magnesium Aluminate Spinel ◽  
Complete Conversion ◽  
Milling Method ◽  
Leaching Solution ◽  
Co Precipitation

Synthesis of magnesium aluminate spinel (MgAl2O4) was investigated by employing ball milling and co-precipitation methods. The starting materials (aluminum hydroxides) were obtained from the purified sodium hydroxide leaching solution of black dross. The characteristics of the synthesized spinel was analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM) images. In this work, the effect of calcination temperature and time on the formation of spinel by the two methods was compared. Calcination temperature showed a great effect on the formation of spinel in both methods. The results showed that the co-precipitation method has many advantages over the ball milling method. In ball milling method, complete conversion of the starting materials to spinel was impossible even at 1500 °C, while complete conversion to spinel was accomplished at 1000 °C for 5 h by the co-precipitation method. The average size of the spinel synthesized at these optimum conditions of the co-precipitation method was about 17 nm. A process can be developed to synthesize spinel from the black dross which is regarded as hazardous materials.

Homogeneous Precipitation Synthesis and Sintering of Magnesium Aluminate Spinel Nanoparticles

2015 ◽  
Vol 659 ◽  
pp. 310-314
Author(s):  
Karn Serivalsatit ◽  
Thanataon Pornpatdetaudom ◽  
Adison Saelee ◽  
Sarut Teerasoradech
Keyword(s):  
Electron Microscopy ◽  
Amorphous Phase ◽  
Precipitation Method ◽  
Magnesium Aluminate ◽  
Homogeneous Precipitation ◽  
Magnesium Aluminate Spinel ◽  
Homogeneous Precipitation Method ◽  
Transmission Electron ◽  
Spinel Powder ◽  
Spinel Nanoparticles

A wide application of magnesium aluminate spinel powder has attracted a number of studies concerning the preparation of magnesium aluminate spinel powder. In this study, a precursor for magnesium aluminate spinel was synthesized by a homogeneous precipitation method using urea as a precipitant. The precursor and the calcined powders were characterized by X-ray diffractometry, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. After precipitation, the precursor was magnesium aluminium hydrate carbonate compound. By calcining, the precursor decomposed to MgO and an amorphous phase after calcining at 600°C. The formation of magnesium aluminate spinel via a reaction between MgO and the amorphous phase was observed after calcining over 800°C. The equiaxed magnesium aluminate spinel nanoparticles with particle size of 20-40 nm were obtained after calcining at 1100°C for 2 hours. Sinterability of the obtained magnesium aluminate spinel nanoparticles was also investigated by sintering compacts of magnesium aluminate spinel nanoparticles in the temperature interval of 1300-1650°C. Sintering temperature of 1600°C allowed the fabrication of dense magnesium aluminate spinel ceramics with relative density >95%.

scholarly journals Synthesis and characterization of a new ZIF-67@MgAl2O4 nanocomposite and its adsorption behaviour

RSC Advances ◽  
2021 ◽  
Vol 11 (22) ◽  
pp. 13245-13255
Author(s):  
Mehdi Davoodi ◽  
Fatemeh Davar ◽  
Mohammad R. Rezayat ◽  
Mohammad T. Jafari ◽  
Mehdi Bazarganipour ◽  
...  
Keyword(s):  
Room Temperature ◽  
Magnesium Aluminate ◽  
Synthesis And Characterization ◽  
Magnesium Aluminate Spinel ◽  
Adsorption Behaviour ◽  
Zeolitic Imidazolate Framework ◽  
Simple Method

New nanocomposite of zeolitic imidazolate framework-67@magnesium aluminate spinel (ZIF-67@MgAl2O4) has been fabricated by a simple method at room temperature with different weight ratios.

Preparation and Characterization of Nanocomposite Calcium Doped Ceria Electrolyte With Alkali Carbonates (NK-CDC) for SOFC

2010 ◽  
Author(s):  
Ghazanfar Abbas ◽  
Rizwan Raza ◽  
Muhammad Ashraf Chaudhry ◽  
Bin Zhu
Keyword(s):  
Electron Microscopy ◽  
Fossil Fuels ◽  
Electrochemical Impedance ◽  
Renewable Energy Sources ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Doped Ceria ◽  
Alternative Source ◽  
Calcium Doped ◽  
Co Precipitation

The entire world’s challenge is to find out the renewable energy sources due to rapid depletion of fossil fuels because of their high consumption. Solid Oxide Fuel Cells (SOFCs) are believed to be the best alternative source which converts chemical energy into electricity without combustion. Nanostructured study is required to develop highly ionic conductive electrolyte for SOFCs. In this work, the calcium doped ceria (Ce0.8Ca0.2O1.9) coated with 20% molar ratio of two alkali carbonates (CDC-M: MCO3, where M = Na and K) electrolyte was prepared by co-precipitation method in this study. Ni based electrode was used to fabricate the cell by dry pressing technique. The crystal structure and surface morphology was characterized by X-Ray Diffractometer (XRD), Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM). The particle size was calculated in the range of 10–20nm by Scherrer’s formula and compared with SEM and TEM results. The ionic conductivity was measured by using AC Electrochemical Impedance Spectroscopy (EIS) method. The activation energy was also evaluated. The performance of the cell was measured 0.567W/cm2 at temperature 550°C with hydrogen as a fuel.

scholarly journals Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications

2019 ◽  
Vol 17 (1) ◽  
pp. 865-873 ◽  
Author(s):  
Muhammad Ramzan Saeed Ashraf Janjua
Keyword(s):  
Electron Microscopy ◽  
Precipitation Method ◽  
Fuel Additive ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
Calcination Process ◽  
Electron Microscopies ◽  
Transmission Electron ◽  
Co Precipitation ◽  
Individual Particles

AbstractThe nano aggregates of cobalt oxide (Co3O4) are synthesized successfully by adopting simple a co precipitation approach. The product obtained was further subjected to the calcination process that not only changed it morphology but also reduces the size of individual particles of aggregates. The prepared nano aggregates are subjected to different characterization techniques such as electron microscopies (scanning electron microscopy and transmission electron microscopy) and X-ray diffraction and results obtained by these instruments are analyzed by different software. The characterization results show that, although the arrangement of particles is compact, several intrinsic spaces and small holes/ pores can also be seen in any aggregate of the product. The as synthesized product is further tested for catalytic properties in thermal decomposition of ammonium perchlorate and proved to be an efficient catalyst.

scholarly journals Bio-assisted preparation of efficiently architectured nanostructures of γ-Fe2O3 as a molecular recognition platform for simultaneous detection of biomarkers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sasikala Sundar ◽  
V. Ganesh
Keyword(s):  
Electron Microscopy ◽  
Iron Oxide ◽  
Photoelectron Spectroscopy ◽  
Simultaneous Detection ◽  
Differential Pulse ◽  
Precipitation Method ◽  
Limit Values ◽  
X Ray ◽  
Co Precipitation ◽  
The Individual

Abstract Magnetic nanoparticles of iron oxide (γ-Fe2O3) have been prepared using bio-assisted method and their application in the field of biosensors is demonstrated. Particularly in this work, different nanostructures of γ-Fe2O3 namely nanospheres (NS), nanograsses (NG) and nanowires (NW) are prepared using a bio-surfactant namely Furostanol Saponin (FS) present in Fenugreek seeds extract through co-precipitation method by following “green” route. Three distinct morphologies of iron oxide nanostructures possessing the same crystal structure, magnetic properties, and varied size distribution are prepared and characterized. The resultant materials are analyzed using field emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, vibrating sample magnetometer and Fourier transform infrared spectroscopy. Moreover, the effect of reaction time and concentration of FS on the resultant morphologies of γ-Fe2O3 nanostructures are systematically investigated. Among different shapes, NWs and NSs of γ-Fe2O3 are found to exhibit better sensing behaviour for both the individual and simultaneous electrochemical detection of most popular biomarkers namely dopamine (DA) and uric acid (UA). Electrochemical studies reveal that γ-Fe2O3 NWs showed better sensing characteristics than γ-Fe2O3 NSs and NGs in terms of distinguishable voltammetric signals for DA and UA with enhanced oxidation current values. Differential pulse voltammetric studies exhibit linear dependence on DA and UA concentrations in the range of 0.15–75 µM and 5 μM – 0.15 mM respectively. The detection limit values for DA and UA are determined to be 150 nM and 5 µM. In addition γ-Fe2O3 NWs modified electrode showed higher sensitivity, reduced overpotential along with good selectivity towards the determination of DA and UA even in the presence of other common interferents. Thus the proposed biosensor electrode is very easy to fabricate, eco-friendly, cheaper and possesses higher surface area suggesting the unique structural patterns of γ-Fe2O3 nanostructures to be a promising candidate for electrochemical bio-sensing and biomedical applications.

scholarly journals Obtaining and Characterizing Thin Layers of Magnesium Doped Hydroxyapatite by Dip Coating Procedure

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 510 ◽  
Author(s):  
Daniela Predoi ◽  
Simona Liliana Iconaru ◽  
Mihai Valentin Predoi ◽  
Mikael Motelica-Heino ◽  
Nicolas Buton ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Antimicrobial Properties ◽  
Dip Coating ◽  
Thin Layers ◽  
Precipitation Method ◽  
Bacterial Strains ◽  
Antimicrobial Studies ◽  
Hydroxyapatite Coatings ◽  
Coating Procedure ◽  
Co Precipitation

A simple dip coating procedure was used to prepare the magnesium doped hydroxyapatite coatings. An adapted co-precipitation method was used in order to obtain a Ca25−xMgx(PO4)6(OH)2, 25MgHAp (xMg = 0.25) suspension for preparing the coatings. The stabilities of 25MgHAp suspensions were evaluated using ultrasound measurements, zeta potential (ZP), and dynamic light scattering (DLS). Using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) information at nanometric resolution regarding the shape and distribution of the 25MgHAp particles in suspension was obtained. The surfaces of obtained layers were evaluated using SEM and atomic force microscopy (AFM) analysis. The antimicrobial evaluation of 25MgHAp suspensions and coatings on various bacterial strains and fungus were realized. The present study presents important results regarding the physico-chemical and antimicrobial studies of the magnesium doped hydroxyapatite suspensions, as well as the coatings. The studies have shown that magnesium doped hydroxyapatite suspensions prepared with xMg = 0.25 presented a good stability and relevant antimicrobial properties. The coatings made using 25MgHAp suspension were homogeneous and showed remarkable antimicrobial properties. Also, it was observed that the layer realized has antimicrobial properties very close to those of the suspension. Both samples of the 25MgHAp suspensions and coatings have very good biocompatible properties.

scholarly journals SERS activity of hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
R. D. Ávila-Avilés ◽  
N. Torres-Gómez ◽  
M. A. Camacho-López ◽  
A. R. Vilchis-Nestor
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Pollen Grains ◽  
Precipitation Method ◽  
Chemical Composition Distribution ◽  
Transmission Electron ◽  
Pollen Surface ◽  
Surface Enhanced Raman ◽  
Enhanced Raman Scattering ◽  
Co Precipitation

Abstract Nature provides remarkable examples of mass-produced microscale particles with structures and chemistries optimized by evolution for particular functions. Synthetic chemical tailoring of such sustainable biogenic particles may be used to generate new multifunctional materials. Herein, we report a facile method for the synthesis of hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template. Silver nanoparticles was biosynthesized using pollen grains as a reduction and stabilization agent as well as a bio-template promoting the adhesion of silver nanoparticles to pollen surface. Fe3O4 nanoparticles were synthesized by co-precipitation method from FeSO4. Hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template were obtained and characterized using Scanning Electron Microscopy and Transmission Electron Microscopy to study the morphology and structure; Energy-Dispersive X-ray Spectroscopy to determine the chemical composition distribution; and Confocal Fluorescence Microscopy to demonstrate the fluorescence properties of hybrid nano-microstructures. Furthermore, these hybrid nano-microstructures have been studied by Surface-Enhanced Raman Scattering (SERS), using methylene blue as a target molecule; the hybrid nano-microstructures have shown 14 times signal amplification.

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