scholarly journals Characterization of ferrite nanoparticles for preparation of biocomposites

2017 ◽  
Vol 8 ◽  
pp. 1257-1265 ◽  
Author(s):  
Urszula Klekotka ◽  
Magdalena Rogowska ◽  
Dariusz Satuła ◽  
Beata Kalska-Szostko

Ferrite nanoparticles with nominal composition Me0.5Fe2.5O4 (Me = Co, Fe, Ni or Mn) have been successfully prepared by the wet chemical method. The obtained particles have a mean diameter of 11–16 ± 2 nm and were modified to improve their magnetic properties and chemical activity. The surface of the pristine nanoparticles was functionalized afterwards with –COOH and –NH2 groups to obtain a bioactive layer. To achieve our goal, two different modification approaches were realized. In the first one, glutaraldehyde was attached to the nanoparticles as a linker. In the second one, direct bonding of such nanoparticles with a bioparticle was studied. In subsequent steps, the nanoparticles were immobilized with enzymes such as albumin, glucose oxidase, lipase and trypsin as a test bioparticles. The characterization of the nanoparticles was acheived by transmission electron microscopy, X-ray diffraction, energy dispersive X-ray and Mössbauer spectroscopy. The effect of the obtained biocomposites was monitored by Fourier transform infrared spectroscopy. The obtained results show that in some cases the use of glutaraldehyde was crucial (albumin).

2013 ◽  
Vol 1506 ◽  
Author(s):  
L. Wang ◽  
B. K. Rai ◽  
S. R. Mishra

AbstractNanostructured Al3+ doped Ni0.75Zn0.25Fe2-xAlxO4 (x = 0.0,0.2,0.4,0.6,0.8, and 1.0) ferrites were synthesized via wet chemical method. X-ray diffraction, transmission electron microscopy, and magnetization measurements have been used to investigate the structural and magnetic properties of spinel ferrites calcined at 950 °C .With the doping of Al3+, the particle size of Ni0.75Zn0.25Fe2-xAlxO4 first increased to 47 nm at x = 0.4 and then decreased down to 37 nm at x = 1. Saturation magnetization decreased linearly with Al3+ due to magnetic dilution. The coercive field showed an inverse dependence on the particle size of ferrites.


Author(s):  
Nguyen Ca ◽  
N. D Vinh ◽  
Phan Van Do ◽  
N. T. Hien ◽  
Xuan Hoa Vu ◽  
...  

Tb3+-doped ZnSe quantum dots (QDs) with Tb content in the range of 0.5 - 7% were successfully synthesized by a wet chemical method. X-ray diffraction (XRD) and transmission electron microscopy...


2015 ◽  
Vol 24 (04) ◽  
pp. 1550050 ◽  
Author(s):  
Kieu Loan Phan Thi ◽  
Lam Thanh Nguyen ◽  
Anh Tuan Dao ◽  
Nguyen Huu Ke ◽  
Vu Tuan Hung Le

In this paper, ZnO nanorods were grown by wet chemical method on p-Si (100) substrate to form n-ZnO nanorods/p-Si (100) heterojunction. The optical, electrical, structural properties of n-ZnO nanorods/p-Si(100) heterojunction were analyzed by the photoluminescence (PL) spectroscopy, [Formula: see text]–[Formula: see text] measurement, X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The room temperature PL spectra reveal the good optical property of the heterojunction with strong UV peak at 385[Formula: see text]nm. The ZnO nanorods were vertically well-aligned on p-Si (100) and had an average height of about 1.6[Formula: see text][Formula: see text]m. The n-ZnO nanorods/p-Si (100) heterojunction also exhibits diode-like-rectifying-behavior.


1998 ◽  
Vol 13 (9) ◽  
pp. 2580-2587 ◽  
Author(s):  
K. H. Ryu ◽  
J-M. Yang

The characteristics of nanosized silicon nitride powders with doped Y2O3 and Al2O3 fabricated by a plasma-reacted chemical process were investigated. The chemical compositions of the powders were analyzed by wet chemical analysis. The morphology and the size distribution were determined by transmission electron microscopy (TEM). TEM with energy dispersive spectroscopy (EDS) was used to verify the existence of sintering additives in each individual particle. The crystal structure of the powders was identified by the selected area diffraction pattern (SADP). X-ray diffraction (XRD) technique was used for phase analysis and the measurement of degree of crystallinity. The characteristics of chemical bonding was analyzed by using Fourier transform infrared spectroscopy (FTIR).


2018 ◽  
Vol 24 (8) ◽  
pp. 5519-5522
Author(s):  
Israr Ul Hassan ◽  
Liji John ◽  
R. Selwin Joseyphus ◽  
I. Hubert Joe ◽  
R. S Amritha ◽  
...  

Synthesis of nanocrystalline cadmium oxide particles were explored by the reaction of inorganic precursor (cadmium chloride) and alkali (sodium hydroxide) via modified wet-chemical method followed by annealing at various temperatures (250, 500 and 750 °C). The structural, optical and morphological studies of cadmium oxide samples were carried out by X-ray diffraction, infrared, ultraviolet-visible, and scanning electron microscope techniques. From X-ray diffraction analysis, it was confirmed that cadmium oxide particles furnish a face centred cubic phase structure and revealing a grain size of around 59 nm. The scanning electron microscope micrographs admit that cadmium oxide samples are agglomerated and have spherical shapes. The bonding deformation and stretching frequency results of cadmium oxide samples were obtained from infrared spectra. The corresponding increase in calcination temperatures has shown an increase in particle size while as no change was found in band gape. These results attribute that the variation in annealing temperature has a significant role on the crystalline nature, grain size and its optical properties. Furthermore, the synthesized cadmium oxide samples were examined for bioactivity analysis.


2010 ◽  
Vol 25 (10) ◽  
pp. 2042-2046
Author(s):  
R.M. Catchings ◽  
A.N. Thorpe ◽  
J.R. Grant ◽  
R. Douglas ◽  
C. Viragh ◽  
...  

Bismuth telluride (Bi2Te3) systems containing 2%, 4%, and 8% of iron were prepared using a low temperature wet chemical method. Iron oxide nanoparticles were formed when the samples were heated in hydrogen at 250 °C for at least six hours. The samples were characterized by x-ray diffraction, magnetization, magnetic susceptibility, x-ray photoelectron spectroscopy, Mössbauer spectroscopy, and wet chemical analysis measurements. The nanoparticles of iron oxide were identified as γ-Fe2O3 with a particle size of ˜5 nm.


2016 ◽  
Vol 17 (4) ◽  
pp. 281 ◽  
Author(s):  
J. Li ◽  
J.W. Ko ◽  
W.B. Ko

<p>BaTiO<sub>3</sub>-TiO<sub>2</sub> nanoparticles were fabricated by a wet-chemical method using barium chloride dihydrate (BaCl<sub>2</sub>·2H<sub>2</sub>O), titanium dioxide (TiO<sub>2</sub>), and oxalic acid (C<sub>2</sub>H<sub>2</sub>O<sub>4</sub>) as precursors. BaTiO<sub>3</sub>-TiO<sub>2</sub>-graphene nanocomposites were obtained by heating the BaTiO<sub>3</sub>-TiO<sub>2</sub> nanoparticles with graphene in an electric furnace at 700 °C for 2 h. X-ray diffraction analysis revealed that the resulting products were BaTiO<sub>3</sub>-TiO<sub>2</sub>-graphene nanocomposites. Scanning electron microscopy revealed the morphologyof the nanocomposites. UV-vis spectrophotometry was used to analyze the photocatalytic degradation of several organic dyes using the BaTiO<sub>3</sub>-TiO<sub>2</sub>-graphene nanocomposites as a photocatalyst under ultraviolet irradiation at 254 nm.</p>


2019 ◽  
Vol 37 (2) ◽  
pp. 238-243
Author(s):  
Omer Kaygili ◽  
Niyazi Bulut ◽  
Tankut Ates ◽  
Ismail Ercan ◽  
Suleyman Koytepe ◽  
...  

AbstractIn the present study, the dopant effect of Zn on the crystal structure, thermal properties and morphology of magnesium aluminate (MgAl2O4) spinel (MAS) structure was investigated. A pure and two Zn-containing MASs (e.g. MgAl1.93Zn0.07O4 and MgAl1.86Zn0.14O4) were synthesized for this purpose via a wet chemical method, and the as-prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, differential thermal analysis (DTA), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy techniques. It was found that the crystal structure, thermal properties and morphology of the MAS system change with the increase in the amount of Zn. MgO phase formation was observed. The values of the lattice parameter, unit cell volume and crystallite size increased, and the crystallinity percentage decreased. The morphology was also affected by adding of Zn.


2003 ◽  
Vol 789 ◽  
Author(s):  
Yvonne Axmann ◽  
Alke Petri ◽  
Heinrich Hofmann

ABSTRACTZnS:Mn2+ nanoparticles were synthesized via a wet chemical method with L-cysteine as the stabilizing agent. The obtained aqueous dispersions show an orange luminescence, which is typical for the 4T1 → 6A1 transition within the Mn2+ d-orbitals. The fluorescence quantum yield has been determined with quinine sulphate as a dye reference. It can be increased after formation of a SiO2 shell around the particles by a factor of three. The particle size was determined with transmission electron microscopy (TEM), X-ray diffraction and PCS measurements.


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