Studying the Effect of Cobalt Doping on Optical and Magnetic Properties of Zinc Oxide Nanoparticles

Azab, A. A.; Esmail, S. A.; Abdelamksoud, M. K.

doi:10.1007/s12633-018-9902-4

Cited by 41 publications

(17 citation statements)

References 50 publications

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“…The ferromagnetic behavior in the present samples resulted from the superexchange interaction between the electrons and holes in the 3d shell in the transition metal ions (Co 2+ -Co 3+ ). Increasing the concentration of cobalt increased the saturation magnetization from 0.157 (emu/g) to 0.24 (emu/g) confirming that the superexchange interaction between the 3d electron in the transition metals dominated the effect of diamagnetic constituents in the samples (Gandhi et al 2014;Tseng et al 2014;Azab et al 2018). The ferromagnetic parameters are listed in Table 1.…”

Section: Magnetization (M-h) Curvesmentioning

confidence: 73%

Nanoceramics and novel functionalized silicate-based magnetic nanocomposites as substitutional disinfectants for water and wastewater purification

Nahwary

Hemdan

Abia

2020

Environ Sci Pollut Res

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Herein, we successfully synthesized nano-porous Co 2 O 3 /Cu 2 O 3 : Al 2 O 3 : SiO 2 ((0, 5, 7, 9) Co-CAS) using the acidic sol-gel approach and calcined at 800°C for 4 h. The crystallization behavior and spectroscopic properties were investigated using X-ray diffraction, field emission-scanning electron microscopy, and Fourier-transform infrared absorption spectra analysis. The antibiotic properties of the nano-porous CAS, 5Co-CAS, and 9Co-CAS magnetic nanocomposites was studied against some potentially pathogenic bacteria in water and wastewater samples. The bacteria tested included Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis. Incorporating Co 2 O 3 resulted in the identification of three peaks at 2θ = 10.2°, 13.4°, and 15°. The introduction of cobalt nanoparticles created a ferromagnetic behavior in the CAS nanoceramic, with the magnetic moment and saturation values increasing with increased Co 2 O 3 doping. 9Co-CAS was most potent against all the tested pathogens with minimum inhibitory concentrations of 25 mg/L within 40 min for E. coli and P. aeruginosa and 50 mg/L within 10 min for S. enterica; the lowest antibacterial activity was observed with the unmodified CAS. The findings revealed that the manufactured nanocomposite materials were potent disinfectants with a promising application for water and wastewater treatment.

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Section: Magnetization (M-h) Curvesmentioning

confidence: 73%

Nanoceramics and novel functionalized silicate-based magnetic nanocomposites as substitutional disinfectants for water and wastewater purification

Nahwary

Hemdan

Abia

2020

Environ Sci Pollut Res

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“…11. VSM analysis for undoped ZnO nanostructures shows a negative linear behavior at room temperature which indicates a diamagnetic behavior of ZnO nanostructures that has been reported by several research groups (Gandhi et al, 2014;Zhou et al, 2007;Azab et al, 2018Azab et al, , 2019. The reason for this is that the paired electrons of the 2p orbital of oxygen and 3d orbital of zinc combine to form ZnO.…”

Section: Magnetic Propertiessupporting

confidence: 54%

Coupling between γ-irradiation and synchrotron-radiation-based XAFS techniques for studying Mn-doped ZnO nanoparticles

Imam¹,

Harfouche²,

Azab³

et al. 2022

J Synchrotron Rad

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γ-Irradiation and synchrotron-radiation-based X-ray absorption fine-structure (XAFS) spectroscopy have been used to induce structure disorder through the interaction of γ-rays (200 kGy) with fabricated Mn-doped ZnO nanoparticles (NPs) and then to examine thoroughly the resultant structural change. The extracted electronic/fine XAFS structural parameters reflect a compositional and γ-irradiation co-dependence. The average crystal structure of samples prepared by the sol-gel method was investigated by X-ray diffraction (XRD). A detailed structural XRD data analysis was carried out by applying a Rietveld refinement using the MAUD program. XAFS spectra were collected at the Zn K-edge (9659 eV) in transmission mode and at the Mn K-edge (6539 eV) in fluorescence mode. Direct evidence of the solubility of Mn ions in the ZnO structure was demonstrated by fitting the extended-XAFS (EXAFS) signal. Near-edge XAFS (XANES) analysis provided the oxidation states of Zn and Mn ions through fingerprint XANES spectra of the sample along with those of standard compounds. Linear combination fitting showed that the most fit chemical forms of Zn and Mn in the samples are ZnO and MnO, respectively. The oxidation states of both Zn and Mn XAFS absorbers were confirmed from pre-edge fitting. The results of the magnetic measurements were explained in light of the average and electronic/local structural information obtained from XRD, XANES and EXAFS techniques. The magnetic properties of the samples translate into an induced change in the average crystal and electronic/local structures upon Mn concentration change and γ-irradiation. XRD confirmed the successful preparation of hexagonal Mn-doped ZnO NPs with a crystallite size in the range 33–41 nm. Both XRD and EXAFS analysis detected a minor amount of Mn3O4 as a secondary phase. XANES and EXAFS provided information exploring the outstanding potential of the utilized protocol for detecting precisely the presence of the secondary phase of Mn3O4, which changes with Mn content (x). Mean-square relative displacement (σ2) values extracted from the EXAFS fitting were found to grow for Zn–Zn/Mn paths demonstrating the substitution of Mn/Zn into Zn crystal sites. The EXAFS analysis explains the reasons behind the enhancement in the magnetic properties and shows that the Mn doping content at x = 0.05 produces the most local atomic disorder in ZnO NPs. There is a strong harmony among the XRD, XANES, EXAFS and magnetization behavior of the Mn-doped ZnO NPs. Maximum magnetization was acquired at an Mn content of 0.05. γ-Ray-irradiated Zn1–x Mn x O NPs are recommended as optimized candidates for showing the diversity of the applications.

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“… 2 The control of defects, along with the control in shape and size, is essential for the application of ZnO as defects can alter the properties. DMS can be synthesized by different techniques like chemical precipitation, 29 sol–gel, 30 chemical bath deposition, 31 but the hydrothermal method is very simple and cost-effective to obtain nanostructures on a large scale. Advantages of this hydrothermal synthesis are that it lowers the activation energy that is required for the formation of the final product phase; it enhances the chemical reactivity of the reactants; hence reactions can proceed at low temperatures.…”

Section: Introductionmentioning

confidence: 99%

Diluted magnetic semiconductor properties in TM doped ZnO nanoparticles

et al. 2022

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Studying the Effect of Cobalt Doping on Optical and Magnetic Properties of Zinc Oxide Nanoparticles

Cited by 41 publications

References 50 publications

Nanoceramics and novel functionalized silicate-based magnetic nanocomposites as substitutional disinfectants for water and wastewater purification

Nanoceramics and novel functionalized silicate-based magnetic nanocomposites as substitutional disinfectants for water and wastewater purification

Coupling between γ-irradiation and synchrotron-radiation-based XAFS techniques for studying Mn-doped ZnO nanoparticles

Diluted magnetic semiconductor properties in TM doped ZnO nanoparticles

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