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In the present paper, nickel cobalt ferrite (Co0.5Zn0.5Fe2O4) nanoparticles were synthesized using a template-assisted hydrothermal method. Carboxymethyl cellulose was used as the templating agent for controlling the morphology of the Co0.5Zn0.5Fe2O4 nanoparticles. The synthesized nanoparticles were characterized using X-ray diffraction, scanning e...
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... change in morphology can be related to the structure of the CMC monomer, which contained two substituted cyclohexane hexagonal rings with some substituted radicals (Figure 3). The substituted radicals were composed of a hydroxyl radical and a sodium acetate radical on two sides of the hexagonal ring. ...Similar publications
The synthesis of Fe 3 O 4 magnetic nanoparticles (MNPs) from iron ore as source of Fe3O4 has been done. Fe 3 O 4 MNPs were characterized by X-ray diffractometer (XRD) and Transmission Electron Microscope (TEM) for phase and size, Fourier Transform Infrared (FTIR) Spectrometer for bonding, and Vibrating Sample Magnetometer for magnetic properties. X...
Epoxy/nickel–zinc ferrite (NZFO) hybrid nanocomposites have been successfully prepared using UV-curing process, and their composition, structure, morphology, magnetic and microwave absorption have been characterized at the same time. The results from FTIR and TGA show that NZFO and the epoxy are uniformly combined by UV-curing process. The magnetic...
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We report the effect of In on superparamagnetic CoInxFe2-xO4 (x = 0.00, 0.05, 0.10 and 0.15) nanoparticles (NPs) prepared through one step hydrothermal method. The trace of In ions in the matrix causes to change the structural and magnetic properties of CoFe2O4 which is confirmed by XRD and magnetic analyses. X-ray diffraction (XRD) investigation a...
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Citations
... The images from the SEM confirmed the growth of uniform structure [3,82,142,146,178]. Moreover, the influence of change in doping concentration over the size of the grains has also been studied [9,82,92,95,97,103,114,122,132,142,147]. Furthermore, the agglomerated microstructure of ferrite particles has also been shown in many investigations [69,83,84,100,114,116,120,124,126,136,175,180]. ...
The magnetic qualities of ferrites make them suitable for use in industries such as shielding, biosensors, memory devices, permanent magnets, transformers, pollution control, gyromagnetic gadget, microwave absorption, clinical gadgets, catalysis, pigments, etc. In this article, the current state of the hexagonal and spinel ferrites is discussed along with its background, characteristics, applications, categorization, and preparation. It focuses on a relative comprehension of four methods of preparation, magnetic nature, and classification of the ferrites. The article highlights XRD, SEM, TEM, VSM, spectroscopy, thermal analysis, and VNA results. Based on the chemical composition & different heat treatments during the synthesis method; the electric, magnetic & crystallographic properties of ferrites can be altered. Elements such as Ni, Fe & Co are ferrites that have significance in manufacturing & innovation since they have natural magnetic moments under the Curie temperature. It is the goal of the current study to make this scientific topic easier to understand.
... The properties of ferrites can be significantly affected by the synthesis method of ferrites. The most popular methods for synthesis of ferrites are sol-gel [2,3,42,68,69,92,94,95,97,98,100,105,106,[112][113][114][115][116][117][118][119] hydrothermal [2,73,77,78,93,[119][120][121][122][123][124][125][126], co-precipitation [2,11,31,79,83,102,104,119,[127][128][129][130][131][132][133][134][135][136][137] and solid-state method [2,64,67,74,76,82,84,89,99,101,103,108,119,[138][139][140][141][142][143][144][145][146][147][148]. Some other methods are also used such as inert gas condensation [119,149], micro-emulsion [119,[150][151][152], electrochemical method [153][154][155], thermal decomposition [156,157], electro-spinning method [2,[158][159][160], etc. for synthesis of ferrites. ...
... It refers to the study of shape, size and structure of ferrites. It is clearly noticed in cited literature that the ferrite particles have consisted several different shapes such as spherical [68,69,101,104,124,126,127,132,136,174,179], needle shaped [104,127,180], regular hexagonal [84,92,93,100,103,105,142,143,146,174], flat platelet [96,97,103,122,136,180], large ball shaped [120], polygonal [76], pyramidal [105,179], rod like shape [115], cuboidal [84], etc. The SEM image demonstrated the development of homogeneous microstructure [3,82,142,146,178]. ...
... The SEM image demonstrated the development of homogeneous microstructure [3,82,142,146,178]. Furthermore, the effect of the variation in doped concentration on grain size of ferrites has also been analysed [9,82,92,95,97,103,114,122,132,142,147]. Moreover, several studies have shown the agglomerated microstructure of ferrite particles [69,83,84,100,114,116,120,124,126,136,175,180]. ...
The research on ferrites is fast moving owing to their exponentially growing usage in magnetic shielding, magnetic biosensors, magnetic recording devices, information storage, mobile communication, electronic devices, gyromagnetic device, medical devices, transformers, pollution control, catalysis, and pigments. This review comprises the present state of the art on hexagonal ferrites (HFs) and spinel ferrites (SFs). The article covers the background, properties, classification schemes, synthesis and characterization of ferrites. It focuses on a comparative understanding of four synthesis routes, magnetic properties and characterization of the ferrites. The article emphases X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, spectroscopy, thermal analysis and vector network analyser results. The present work is meant for the faster understanding of this research area
... These cubic ferrites are using in different areas of daily life, for example: recording disks or tapes, magnetic devices, active components of ferro-fluids and microwave absorbers. The purpose to synthesized the Ca doped Co-Zn ferrite is that to study it effect on different properties of Co-Zn ferrites like corrosion resistivity, anisotropy, magneto-optical, magneto-crystalline and chemical stability (He, 2011). Now a days, different techniques are using to synthesized Ca doped Co-Zn ferrite. ...
Co-Zn ferrites have great magneto-striction, high corrosion resistivity and excellent chemical stability. We can control the ferromagnetic properties and paramagnetic properties of Co-Zn ferrites by changing its particle distribution and particle size. There are different types of techniques are available to synthesis Co-Zn ferrites like co-precipitation, sol gel and auto-combustion method etc. In this research, we will synthesize Co-Zn ferrites by micro-emulsion technique and substitute Ca in it with different composition. XRD results showed that samples were in single phase ferrite. Particle size was between the ranges of 34-14nm. Average lattice constant were 8.11-8.18Ao. FT-IR conform the results obtained by XRD. SEM conform the morphology of the samples and its grain size. Grain size decreased with increased of the concentration of Ca in Co0.6-x-Zn0.CaxFe2O4. TGA results were found in agreement with previous literatures
... Ferrites continue to be fascinating magnetic material because of their potential applications, such as high-density information, ferrofluids, magnetic resonance imaging, biomedical diagnostics, drug delivery, high-frequency electronic device, sensors, and magnetic refrigerator system, etc. [4]. Ferrites are usually prepared by autocatalytic decomposition [5], hydrothermal [6], reverse micelles [7], microwave combustion [8], sol-gel [9] and co-precipitation [10]. The properties of the ferrite are sensitive to the ferrite compositions and synthesis techniques. ...
Dielectric properties of Zn substituted cobalt ferrite (Co 1-x Zn x Fe 2 O 4 ) magnetic nanoparticles with various Zn concentrations ( x = 0.2-0.8) have been successfully investigated. The structure of the prepared samples Co 1-x Zn x Fe 2 O 4 confirmed to be cubic spinel structure using X-ray diffraction analysis. The crystallite size of the sample was found to decrease with the increase of zinc content from 11.6 nm to 9.8 nm, while the lattice parameters found to increase with the increase of zinc from 8.18 to 8.25 Å. For Zinc x = 0.6 at frequency 5 kHz have the highest real dielectric constant ( ɛ' ) was 678.8 and imaginary dielectric constant ( ɛ'' ) was 833.3. The maximum impedance found at zinc x = 0.3 was 138.5. The dielectric constant decrease rapidly with increasing the frequency and then reaches the constant value where the frequency was used from 5-120 kHz.
... The FESEM micrographs of commercially available and as-synthesized Co 0.5 Zn 0.5 Fe 2 O 4 demonstrated same spherical surface morphology of having diameter less than 100 nm ( Fig. 3a and b). Similar type of surface morphology of Co 0.5 Zn 0.5 Fe 2 O 4 was also observed in previous study [27]. Transmission electron microscopy was used to further explore the structural symmetry and crystallographic phase orientation of as-synthesized catalyst by assessing the SAED pattern and lattice structure at molecular level. ...
A low-cost electrochemically active oxygen reduction reaction (ORR) catalyst is obligatory for making microbial fuel cells (MFCs) sustainable and economically viable. In this endeavour, a highly active surface modified ferrite, with Co and Zn bimetal in the ratio of 1:1 (w/w), Co0.5Zn0.5Fe2O4 was synthesised using simple sol-gel auto combustion method. Physical characterisation methods revealed a successful synthesis of nano-scaled Co0.5Zn0.5Fe2O4. For determination of ORR kinetics of cathode, using Co0.5Zn0.5Fe2O4 catalyst, electrochemical studies viz. cyclic voltammetry and electrochemical impedance spectroscopy were conducted, which demonstrated excellent reduction current response with less charge transfer resistance. These electrochemical properties were observed to be comparable with the results obtained for cathode using 10% Pt/C as a catalyst on the cathode. The MFC using Co0.5Zn0.5Fe2O4 catalysed cathode could produce a maximum power density of 21.3 ± 0.5 W/m³ (176.9 ± 4.2 mW/m²) with a coulombic efficiency of 43.3%, which was found to be substantially higher than MFC using no catalyst on the cathode 1.8 ± 0.2 W/m³ (15.2 ± 1.3 mW/m²). Also, the specific power recovery per unit cost for MFC with Co0.5Zn0.5Fe2O4 catalysed cathode was found to be 4 times higher as compared to Pt/C based MFC. This exceptionally low-cost cathode catalyst has enough merit to replace costly cathode catalyst, like platinum, for scaling up of the MFCs.
... These supercapacitors have plentiful potential applications such as power electronics, electric vehicles, sensor, and computer backup etc., [6] . Zinc ferrite nanoparticles added with cobalt modified the properties such as magnetic properties, high corrosion resistivity and chemical stability [7] . Zinc ferrite nanoparticles possess normal spinel structure, where all the Zn 2+ ions are occupied at a sites namely tetrahedral, and all the Fe 3+ ions are occupied at B sites namely octahedral [8] . ...
Cobalt zinc ferrite nanoparticles, CoxZn1-xFe2O4(x=0.3, 0.5 and 0.7), have been prepared by the co-precipitation method and annealed at different temperatures. The structural and magnetic properties of the samples were determined and characterized by X-ray analysis showed that the samples were cubic spinel. Enhancement of crystallinity and particle size was observed with the increase in annealing temperatures. The increase in cobalt concentration in zinc ferrite nanoparticles resulted in the decrease of lattice parameter, unit cell volume and increase X-ray density were observed. Thermo gravimetric and differential thermal analysis (TG/DTA) method was used to confirm the formation of cobalt zinc ferrite nanoparticles. FTIR spectra confirm that the presence of metal oxide stretching vibration is attributed to the formation of cobalt zinc ferrite nanoparticles. The cobalt zinc ferrite nanoparticles annealed at 600 °C were characterized by using FESEM with EDAX, FETEM with SAED pattern. The surface morphology of cobalt zinc ferrite nanoparticles studied through FESEM and FETEM indicate that the particles were in spherical shape. EDAX analysis revealed the presence of Co, Zn, Fe and O content in cobalt zinc ferrite nanoparticles, and it's varied with the Co concentration. The M-H curve of cobalt zinc ferrite nanoparticles shows a ferromagnetic behavior at room temperature. The magnetic measurements showed that the saturation magnetization and coercivity increased with increasing the cobalt content in zinc ferrite nanoparticles, and it is suitable for magnetic devices. The electrochemical performance of the nickel zinc ferrite nanoparticles was investigated by CV analysis. The higher capacitance value 449 Fg-1 was observed for the scanning rate 5mVs-1 for Ni0.7Zn0.3Fe2O4 reflecting the good quality of nickel zinc ferrite nanoparticles, and it was suitable for supercapacitor application.
... During the last decade, there was a growing interest in NPs of magnetic spinel ferrites due to their vast applications in various fields such as data storage devices, sensors, nanodevices, photoelectric devices, photocatalysis, magnetic pigments and microwave devices [1][2][3]. Among spinel ferrites, cobalt zinc ferrite NPs demonstrate improved properties such as magnetostriction, magneto-optical properties, chemical stability and high corrosion resistivity [4]. The magnetic properties of NPs of spinel ferrites are strongly dependent on particle size and morphology. ...
In this paper, cobalt zinc ferrite (Co0.5Zn0.5Fe2O4) nanoparticles (NPs) have been prepared using chemical co-precipitation method. In order to investigate the annealing induced effects on their various physical properties, the prepared samples have been annealed at 500 °C, 650 °C and 1000 °C and then compared with as-prepared sample. X-ray diffraction (XRD) patterns of as-prepared and annealed samples at various temperatures exhibit single phase spinel structure. Enhancement in crystallinity and crystallite size is observed with the increase in annealing temperature. The annealing has also greatly influence the morphology and grain size of prepared NPs. The Co0.5Zn0.5Fe2O4 NPs have shown remarkable enhancement in magnetic moment with increase in annealing temperature. The bandgap energies of Co0.5Zn0.5Fe2O4 NPs have been measured via UV Spectrometer and observed to decrease with annealing temperature. FTIR spectra of the samples reveal the presence of both high frequency and low-frequency bands due to tetrahedral and octahedral sites, which corroborate well with the XRD results. The observed characteristics of cobalt zinc ferrite NPs as a function of annealing temperature are the rising contender for many data storage and nanodevice applications. Finally, the genotoxicity of prepared nanoferrites has been checked via comet assay.
... It has been observed that sulfides in nanoscale also function as photocatalyst with preferable catalytic ability [10]. Recently, various morphologies of copper sulfide including nanowires [11], nanodisks [12], hollow spheres [13], and flower-like structures [14] were prepared by thermolysis [15], microemulsion [16], hydrothermal [17,18], solvothermal [19,20], and polyol route [21], one-step solid-state reaction [22], chemical vapor deposition (CVD) [23], wet chemical method [24], and templateassisted [25] and sonochemical methods [26] which have been reported. Among them, the hydrothermal method is the most common synthesis technology, because of its ease of operation with less-expensive equipment. ...
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.
This review highlights the different strategies of modified TiO2 nanostructure as heterogeneous catalyst in organic transformations. The modification in TiO2 nanostructure have been achieved by doping with metal and non-metal, composing with other material such as metals, metal oxides, nonoxides, semiconductor and nanostructure carbon materials. The influence of modification in TiO2 nanostructure on catalytic properties in organic synthesis also discussed. Different modifications of TiO2 extend the catalyst selectivity and reusability over unmodified TiO2 nanoparticles. Recent investigations have shown that modified TiO2 nanostructures utilised as active catalysts or catalyst support in organic transformations including C-C, C-N, C-S, C-O bond formation reactions, multicomponent reactions (MCR), oxidation- reductions.
