Preparation of Co3O4 Nanostructures via a Hydrothermal- Assisted Thermal Treatment Method by Using of New Precursors

2017 ◽  
Vol 36 (2) ◽  
pp. 107-112 ◽  
Author(s):  
Sousan Gholamrezaei ◽  
Masoud Salavati-Niasari ◽  
Hassan Hadadzadeh ◽  
Mohammad Taghi Behnamfar

AbstractCo3O4 nanostructures have been synthesized via a hydrothermal-assisted thermal treatment process. A new complex formulated as [Co(py)2(H2O)2(NO3)2] was synthesized, and then used to prepare Co3O4 nanostructures. Cubic phase of spinel Co3O4 nanostructures with particle size of about 39 nm could be produced after calcination of the Co(OH)2 materials prepared with hydrothermal method at 160 °C for 15 h. Using of inorganic precursors decreased the time and temperature of Co3O4 preparation. The effect of pH on the morphology of the product s synthesized by hydrothermal reactions was investigated. It was found that the best morphology was achieved on pH=8, where was not prepared any precipitation. In this method, we could decrease the reaction temperature in synthetic rout to fabricate Co3O4 nanostructures. Nanostructures were characterized by SEM, TEM, X-ray diffraction (XRD), UV–visible, Fourier transformed infrared (FT-IR) spectroscopy and Nuclear magnetic resonance (1H-NMR).

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Mahmoud Goodarz Naseri ◽  
Elias B. Saion ◽  
Ahmad Kamali

This study reports the simple synthesis of MFe2O4 (where M=Zn, Mn, and Co) nanoparticles by a thermal treatment method, followed by calcination at various temperatures from 723 to 873 K. Poly(vinyl pyrrolidone) (PVP) was used as a capping agent to stabilize the particles and prevent them from agglomeration. The characterization studies were conducted by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average particle sizes were obtained by TEM images, which were in good agreement with the XRD results. Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of metal oxide bands for all the calcined samples. Magnetic properties were demonstrated by a vibrating sample magnetometer (VSM), which displayed that the calcined samples exhibited superparamagnetic and ferromagnetic behaviors.


2011 ◽  
Vol 10 (03) ◽  
pp. 441-445 ◽  
Author(s):  
M. KARL CHINNU ◽  
L. SARAVANAN ◽  
R. JAYAVEL ◽  
C. M. RAGHAVAN ◽  
K. VIJAI ANAND ◽  
...  

Cadmium sulfide nanoparticles have been synthesized by hydrothermal method using cadmium acetate, thiosemicarbazide, and sodium hydroxide as precursors with hexamethylene tetramine as the surfactant. From the X-ray diffraction analysis, it is observed that synthesized CdS nanoparticles show cubic phase. The presence of HMTA in CdS was confirmed by FT-IR analysis. The bandgap value of CdS nanostructure has been estimated by DRS–UV-Visible spectral analysis. The formation of flower-like nanoclusters was observed using scanning electron microscopy (SEM). The application of CdS nanoparticles in photocatalytic degradation was also studied.


RSC Advances ◽  
2019 ◽  
Vol 9 (38) ◽  
pp. 22143-22152 ◽  
Author(s):  
Alexey Gusev ◽  
Elena Braga ◽  
Ekaterina Zamnius ◽  
Mikhail Kiskin ◽  
Mariya Kryukova ◽  
...  

A series of Zn(ii) complexes with 5-(4-R-phenyl)-3-(pyridin-2-yl)-1,2,4-triazoles have been synthesized and subsequently characterized by single crystal X-ray diffraction, 1H-NMR, FT-IR spectroscopy, elemental analyses, ESI-MS, and PXRD.


2016 ◽  
Vol 35 (7) ◽  
pp. 723-728 ◽  
Author(s):  
Sousan Gholamrezaei ◽  
Masoud Salavati-Niasari ◽  
Hassan Hadadzadeh ◽  
Mohammad Taghi Behnamfar

AbstractMagnetic Co3O4nanostructures were synthesized via a facile thermal treatment method at 700°C by usingtrans-Na[Co(HMTA)2(NO2)4].H2O as a new precursor. In synthetic process Co-complex was prepared by the reaction of Na3[Co(NO2)6] and hexamethylenetetramine (HMTA). Results show that the target Co-complex was synthesized successfully and provides good conditions for preparation of magnetic nanostructures in a facile and surfactant-free method to prepare the octahedral nanostructures. Precursors and nanostructures were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), UV–visible, Fourier transform infrared (FTIR) spectroscopy and alternating gradient force magnetometer (AGFM). It is found that the Co3O4nanostructures exhibit a ferromagnetic behavior with a saturation magnetization of 8.69 emu/g and a coercivity of 305.3 Oe at room temperature.


2003 ◽  
Vol 788 ◽  
Author(s):  
Jieming Cao ◽  
Jun Wang ◽  
Jinsong Liu ◽  
Shuquan Chang ◽  
Baoqing Fang ◽  
...  

ABSTRACTBramble-like mesostructured nickel oxide/surfactant fibers were synthesized by using anionic surfactants (sodium dodecylsulfonate or sodium dodecylsulfate: SDS) as templates, and nickel salts as inorganic precursors, via the “S-I+” route in alkaline condition. The as-prepared samples were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and thermogravimetry-differential thermal analysis (TG/DTA) techniques. Such form of mesostructure nickel oxide is found for the first time and is believed to have potential applications in catalysis, host-guest chemistry, and electrochemical devices.


2018 ◽  
Vol 7 (4.37) ◽  
pp. 127
Author(s):  
Muhanned Abdul-Redhah Aidan ◽  
Wafaa Mahdi Alkoofee ◽  
Ala`a A. Sultan ◽  
Wessal M. Khamis ◽  
Sinan Medhat

The polymers derived from heterocyclic rings like imidazole was prepared and supported to produce catalytic active supported catalyst. This catalyst was characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), H NMR and UV-visible spectroscopy. The catalyst showed high catalytic activity in the oxidation of cyclohexene and cyclopentene under optimized conditions. In this work cyclohexene and cyclopentene were selected as model alkene for determination the capacity of the prepared imidazole polymer catalyst under optimized conditions of temperature and time of reaction. The catalyst could be readily separated from the catalytic system using uploading 3-5 milligrams of Copper(II), Nickel(II) and Cobalte(II) ions with the surface of polymer the conversion them to nano-particle which are identified by x-ray diffraction. For this research, a statistical method called Response Surface Methodology (RSM) has been used to economize the number of experiments and their meaningful interpretation. The effect of metallated polymer with Copper(II), Nickel(II) and Cobalte(II) were taken to increase the efficiency of oxidation. Optimization results for 0.33 mmole cyclohexene and cyclopentene showed that maximum oxidation efficiency 90. % was achieved at the optimum conditions: catalyst amount 350 mg, temperature 70.0, time 3.30 h and oxidant= 5.25 m mole.   


2016 ◽  
Vol 852 ◽  
pp. 538-541
Author(s):  
Shu Yu Zhong ◽  
Hai Shao Ye ◽  
Ji Qi Jiang ◽  
Qian Yang ◽  
Pei Song Tang

Using La (NO3)3·6H2O, NH4VO3, citric acid as the main raw materials, nanocrystalline LaVO4 sample was prepared by microwave method. The structure and morphology of sample were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible diffuse reflectance spectroscopy (DRS) and Fourier Transform Infrared (FT-IR) spectroscopy. The photocatalytic activity of LaVO4 was studied for methyl orange (MO) used as simulated sewage. The XRD and SEM showed that the particle size of LaVO4 was about 80-100 nm. The DRS showed that LaVO4 had optical absorption onset of 356 nm, indicating the optical band gap of 3.48 eV. The FT-IR showed that LaVO4 had vibration peaks of Fe-O and V-O bond. Under UV-light, the photocatalytic experiment indicated that the prepared LaVO4 nanocrystalline had highly photocatalytic activity for degradation of methyl orange.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.


e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shahram Mehdipour-Ataei ◽  
Leila Akbarian-Feizi

AbstractA diamine monomer containing ester, amide and ether functional groups was prepared and its polymerization reaction with different diisocyanates to give main chain poly(ester amide ether urea)s was investigated. The monomer was synthesized via reaction of terephthaloyl chloride with 4-hydroxybenzoic acid and subsequent reaction of the resulted diacid with 1,8-diamino-3,6-dioxaoctane. The polymers were characterized by FT-IR and 1H-NMR spectroscopic method and elemental analysis. The resulting polymers exhibited excellent solubility in polar solvents. Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited semi-crystalline patterns. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were in the range of 88-112 °C. The temperatures for 10% weight loss (T10) from their thermogravimetric analysis (TGA) curves were found to be in the range of 297-312 °C in air. Also the prepared polyureas showed liquid crystalline character.


2012 ◽  
Vol 727-728 ◽  
pp. 691-696 ◽  
Author(s):  
Tiago Falcade ◽  
Giselle Barbosa de Oliveira ◽  
Diego Pereira Tarragó ◽  
Vânia Caldas de Sousa ◽  
Célia de Fraga Malfatti

Many studies have been reported in the literature related to YSZ films deposited on dense substrate or applied directly on the SOFC anode. However, there are not a lot of studies about the YSZ deposition on the cathode. The present work aims to obtain yttria-stabilized zirconia (YSZ), using the spray pyrolysis technique, for their application as electrolyte in solid oxide fuel cells (SOFC). The films were obtained from a precursor solution containing zirconium and yttrium salts, dissolved in ethanol and propylene glycol (1:1), this solution was sprayed onto a heated LSM porous substrate. The substrate temperature was varied in order to obtain dense and homogeneous films. After deposition, the films were heat treated, aiming to crystallize and stabilize the zirconia cubic phase. The films were characterized by Scanning Electron Microscopy (SEM), thermal analysis, X-ray diffraction and Fourier transform Infrared Spectroscopy (FT-IR).


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