The effect of the cobalt ferrites nanoparticles (CoFe2O4) on the porous silicon deposited by spin coating

Khalifa, Sana Ben; Gassoumi, M.; Dhahbi, Anis Ben; Alresheedi, Faisal; Mahmoud, A.Z.; Béji, Lotfi

doi:10.1016/j.aej.2019.12.031

Cited by 15 publications

(7 citation statements)

References 29 publications

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“…The surface topographical image of cobalt ferrite nanoparticles can be seen in Figure a. The micrograph of CoFe 2 O 4 nanoceramics illustrates regular spherical particles and highly concentrated nanoparticles due to its continuous magnetic moment. , Also, the SEM image of pure SiW 12 O 40 polyoxometalate (Figure b) marks the spherical grain structure. − Also, the spherical structures of gly-modified polyoxometalate ((gly) 3 H[SiW 12 O 40 ]) can be seen in Figure c, which are extensively distributed on the CoFe 2 O 4 substrate in nanosizes. Also, the SEM image of the (gly) 3 H[SiW 12 O 40 ]⊂CoFe 2 O 4 nanocomposite shows nonuniform spherical morphology and agglomeration (Figure d).…”

Section: Resultsmentioning

confidence: 99%

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst

2023

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For manufacturing of clean gasoline with a lower S content (e.g., S <10 ppm), glycine-modified polyoxotungstate ((gly) 3 H[SiW 12 O 40 ]) was immobilized on cobalt ferrite (CoFe 2 O 4 ) nanoceramics via the sol−gel method and employed as an efficient recyclable nanocatalyst in an extractive−oxidative desulfurization (EODS) system. The synthesized (gly) 3 H-[SiW 12 O 40 ]⊂CoFe 2 O 4 nanocatalyst was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) techniques. The optimum conditions for the reaction are given as follows: 50 mL of model and real gasoline, 0.10 g of (gly) 3 H[SiW 12 O 40 ]⊂CoFe 2 O 4 nanocatalyst, 60 min reaction time, 35 °C reaction temperature, 3 mL of AcOH/ H 2 O 2 (V/V ratio of 1:2) as an oxidant system, and 10 mL of CH 3 CN solvent as an extractant. Based on optimization results under the mentioned conditions and the proposed EODS system, the removal efficiency (%) of the model fuel utilizing the (gly) 3 H[SiW 12 O 40 ]⊂CoFe 2 O 4 nanocatalyst can reach 98% with stable reusability up to five times without a noticeable decrease in its catalytic activity. Correspondingly, 0.4986 ppm S content in real gasoline could decline to 0.0145 ppm with a removal yield of 96% under identical conditions. Also, the kinetics of the EODS reactions was found to be pseudo-first order, and the EODS mechanism was put forward through the generation of a peroxometalate intermediate complex with phase transfer properties. The present research shows that liquid fuels can be purified into ultralow-sulfur fuels through highly oxidative desulfurization via the (gly) 3 H[SiW 12 O 40 ]⊂CoFe 2 O 4 nanocatalyst after the EODS process.

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Section: Resultsmentioning

confidence: 99%

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst

2023

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“…Ben Khalifa1 et al [70] found three optical band gaps for CoFe 2 O 4 and CoFe 2 O 4 /Si composite. Kulshrestha et al [71] reported two band gaps for CoFe 2 O 4 annelaed at 1000 °C for 4 h. From table 1 it is clear that the composite sample (MnCr)-LDO 1 wt% /CoFe 2 O 4 recorded the highest band gap values in comparison to other prepared samples.…”

Section: Tem Analysismentioning

confidence: 99%

Influence of adding manganese chromium-layered double oxide on the optical, magnetic and dielectric properties of cobalt spinel ferrite nanoparticles

Rekaby,

Abou-Aly

2023

Phys. Scr.

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Hydrotalcite-like materials such as layered double oxides (LDOs) are promising materials for many technological applications. Linking the multilayer structure of LDOs with the exceptional optical, magnetic, and dielectric properties of spinel ferrites could result in advanced nanocomposites for photovoltaic, magneto-recording, and high-frequency applications. For that purpose, nanocomposites of type manganese chromium-layered double oxide/cobalt spinel ferrite, (MnCr)-LDOx/CoFe2O4 (x = 1, 3, and 5 wt%), were produced by the co-precipitation route. X-ray diffraction (XRD) analysis showed the successful incorporation of MnCr-LDO in CoFe2O4 lattice. After a 5 wt% addition of MnCr-LDO, the lattice parameter of pure CoFe2O4 increased from 8.3832 Å to 8.4136 Å, the crystallite size increased from 18.7 nm to 21.7 nm, and the strain dropped from 2.15 to 2.04. Transmission electron microscopy (TEM) revealed cubic morphologies for (MnCr)-LDOx/CoFe2O4 nanocomposites. Two strong absorbance peaks appeared in the Ultraviolet- visible (UV-vis) spectra (at ∼270 and ∼370 cm−1). The energy band gap and Urbach energy were estimated for the prepared samples. The composite sample (MnCr)-LDO1 wt%/CoFe2O4 recorded the highest band gap values (Eg1 = 3.39 eV, Eg2 = 4.46 eV, and Eg3 = 5.89 eV), while the (MnCr)-LDO3 wt%/CoFe2O4 sample had a relatively high Urbach energy value (1.35 eV). Vibrating sample magnetometer (VSM) analysis showed room temperature ferromagnetic (RTFM) behavior for the prepared composites. The saturation magnetization (Ms) value declined as the MnCr-LDO addition to CoFe2O4 increased, and the (MnCr)-LDO3 wt%/CoFe2O4 sample acquired the highest Ms (64.428 emu g−1) among all the produced composites. Pure CoFe2O4 had a much higher coercivity (Hc = 1158.1 Oe) than (MnCr)-LDOx/CoFe2O4 (x = 1, 3, and 5 wt%) nanocomposites (Hc = 1119.8, 978.48, and 984.16 Oe). Moreover, complex impedance spectroscopy measurements were performed in frequency range of 50 Hz- 5 MHz using Nyquist plots and electric modulus analysis. Nyquist plots were fitted to an analogous electric circuit consisting of a resistor R1 connected in series to two parallel constant phase element- resistor circuits (CPE-R). On the other hand, a different circuit comprises of two CPE, capacitor (C1), and resistor all connected in parallel was used to model CoFe2O4.

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“…As SiO2 mixing increases in cobalt ferrite nanoparticles, the change in crystalline size (D) remains unstable, indicating that SiO2 mixing affects grain growth while sustaining spinel phase formation. The variation in crystalline size can be associated with the disparity between the driving force for grain boundary motion and the retarding force exerted by SiO2 [33] . The increase in silica ratio at 20% lead to an increase in the hopping length at both A and B sites, while there are no discernible changes in the hopping length as silica increases from 40% to 60%.…”

Section: Fourier Transform-infrared Spectroscopymentioning

confidence: 99%

Synthesize CoFe2O4/SiO2 nanoparticles and investigate their magnetic, dielectric, and structural characteristics.

Jumaa,

Saeed,

Mohammad

2023

PJBAS

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Using the sol-gel auto-combustion method, CoFe2O4/SiO2 ferrite nanocomposites (SiO2=0, 20, 40, and 60%) were synthesized. The impact of temperature on a material's structural, magnetic, and electrical characteristics was investigated in this study. Infrared spectroscopy and X-ray diffraction revealed that ferrite crystalizes in the cubic spinel phase, as demonstrated by the use of patterns. Ferrite crystallite size ranges from 33.36 and 46.50 nm (depending on calcination) and 43.89 and 49.05 nm (depending on SiO2 mixing ratio). FE-SEM demonstrates that calcination temperature affects the particle size, as does the amount of SiO2 in the mixture. The EDS was utilized to confirm that each sample contained all of the required elements. VSM measurements were performed on all pure and doped samples that exhibited ferromagnetic behavior at various calcination temperatures and SiO2 mixing ratios. At room temperature, the LCR meter was utilized to carry out an analysis of the electrical properties of each sample. Changes in dielectric characteristics have been observed at frequencies between 50 Hz and 1 MHz, following the theory of Koop's, Maxwell-Wagner polarization, and hopping of electrons. As the frequency was increased observable natural behavior was evident in all of the dielectric properties. In this study silica, coated ferrite (Co1-X Mgx Fe2O4)/SiO2 nanoparticles have been investigated to find out the impact of silica on magnetic and electrical properties.

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The effect of the cobalt ferrites nanoparticles (CoFe2O4) on the porous silicon deposited by spin coating

Cited by 15 publications

References 29 publications

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst

Influence of adding manganese chromium-layered double oxide on the optical, magnetic and dielectric properties of cobalt spinel ferrite nanoparticles

Synthesize CoFe2O4/SiO2 nanoparticles and investigate their magnetic, dielectric, and structural characteristics.

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The effect of the cobalt ferrites nanoparticles (CoFe2O4) on the porous silicon deposited by spin coating

Cited by 15 publications

References 29 publications

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)3H[SiW12O40]⊂CoFe2O4 as a Recoverable and Efficient Nanocatalyst

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)3H[SiW12O40]⊂CoFe2O4 as a Recoverable and Efficient Nanocatalyst

Influence of adding manganese chromium-layered double oxide on the optical, magnetic and dielectric properties of cobalt spinel ferrite nanoparticles

Synthesize CoFe2O4/SiO2 nanoparticles and investigate their magnetic, dielectric, and structural characteristics.

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Product

Resources

About

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst

Extractive–Oxidative Desulfurization of Real and Model Gasoline Using (gly)₃H[SiW₁₂O₄₀]⊂CoFe₂O₄ as a Recoverable and Efficient Nanocatalyst