Showing papers by "Sadik Güner published in 2018"
TL;DR: Chromium-substituted strontium nano-hexaferrites, SrCrxFe12-xO19 (0.0, 0.5 and 0.6), were produced by the hydrothermal route as mentioned in this paper.
88 citations
TL;DR: In this article, the properties of barium hexaferrite (BaFe12O19) powders were analyzed using X-Ray powder diffraction, scan-and-trace analysis, and Fourier transform infrared (FT-IR) analysis.
Abstract: Cu2+ ion substituted nanocrystalline BaFe12O19 [Ba1 − xCuxFe12O19 (0.0 ≤ x ≤ 0.5)] hexaferrite powders were synthesized by sol–gel combustion route and its effects on structure, morphology and magnetic properties of barium hexaferrite (BaFe12O19) were presented. X-Ray Powder Diffraction (XRD), Scanning Electron Microscopy (HR-SEM), Transmission Electron Microscopy (HR-TEM) and Fourier Transform Infrared (FT-IR) analyses revealed the M-type hexagonal structure of all samples. Vibrating sample magnetometer (VSM) analyses showed that all samples have strong ferromagnetic behavior at room temperature. The crystallite size varies in a range of 23.30–35.12 nm. Both HR-SEM and HR-TEM analyses confirmed the hexagonal morphology for products. A minimum of 40.49 and a maximum of 54.36 emu/g estimated specific saturation magnetization (σs) were observed for Ba0.5Cu0.5Fe12O19 and Ba0.9Cu0.1Fe12O19 NPs, respectively. The remnant magnetization (σr) has a minimum value of 21.27 emu/g belonging to Ba0.5Cu0.5Fe12O19 and has a maximum value of 28.15 emu/g belonging to Ba0.7Cu0.3Fe12O19 NPs. The coercive fields are between 1726 Oe and 2853 Oe. K
eff
(calculated effective anisotropy constants) is changing from 2.31 × 105 to 3.23 × 105 Ergs/g. It was observed that the strong magneto-crystalline anisotropy fields, (H
a
) above 11.0 kOe for all samples which confirmed that all samples are hard magnet. Due to their small crystallite size (smaller than 50 nm) and high saturation magnetization, Ba1 − xCuxFe12O19 (0.0 ≤ x ≤ 0.5) nanoparticles can be employed as magnetic recording materials.
59 citations
TL;DR: In this paper, the effect of Cr3+ ion substitution on morphology, structure, optic and magnetic properties of Barium hexaferrite powders was investigated and X-ray powder diffraction (XRD) analyses confirmed the purity of all samples.
46 citations
TL;DR: In this paper, a co-precipitation of spinel spinel nano-nodes was used to obtain the soft ferrimagnetic properties of the spinel nanoparticles.
Abstract: Spinel CuCrxFe2−xO4 (0.0 ≤ y ≤ 1.0) nanoparticles were fabricated by co-precipitation. X-ray diffraction proved the pureness and cubic crystal assembly of products which have the crystallite sizes varying between 16 and 33 nm. The cubic morphology and expected chemical composition, spectral analyses of all sample were accomplished via Scanning electron microscopy along with Energy Dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy respectively. Magnetic and optical characterization of samples were done via Vibrating sample magnetometer, Mossbauer spectroscopy and Diffuse reflectance spectroscopy. Kubelka–Munk model was applied to UV–Vis data for calculating the optical Eg (band gap) values between minimum 1.20 and maximum 1.80 eV. Mossbauer analysis determined the consequence of Cr3+ substitution on isomer shift and quadrupole splitting of all products etc. The specific magnetization (σ-H) hysteresis curves have finite coercivity (in a range of 35–410 Oe) and retentivity (in a range of 0.33–3.84 emu/g) values and reveal the soft ferrimagnetic nature of spinel CuCryFe2−yO4 nanoparticles (NPs). The estimated saturation magnetization Ms value of 35.17 emu/g is maximum for pristine CuFe2O4 NPs and decreases to minimum value of 1.57 emu/g for CuCr0.4Fe1.6O4 NPs due to Cr3+ ion substitution. The calculated squareness ratios less than 0.5 assign the uniaxial anisotropy for all CuCryFe2−yO4 NPs. The magneto-crystalline anisotropy field (Ha) values less than 10.0 kOe except for the composition of CuCr0.2Fe1.8O4 NPs are other magnetic data to reveal the soft magnetic character of samples.
31 citations
TL;DR: In this paper, a novel Ba1−xCuxFe12O19 (0.5 ≤ x) nano-hexaferrites were prepared by a simple and cost-effective sol-gel auto-combustion method using barium nitrates, iron nitrate, copper (II) acetate monohydrate and citric acid, and its structural, optical properties and hyperfine interactions were reported.
Abstract: In this study, a novel Ba1−xCuxFe12O19 (0.5 ≤ x) nano-hexaferrites were prepared by a simple and cost-effective sol–gel auto-combustion method using barium nitrates, iron nitrate, copper (II) acetate monohydrate and citric acid, and its structural, optical properties and hyperfine interactions were reported. Structural properties were analyzed through XRD (X-ray diffraction), Scanning electron microscopy (SEM), and TEM (Transmission electron microscopy), while percent diffuse reflectance spectroscopy (DRS) and Mossbauer spectrometer were used for analyzing the optical and magnetic properties of the resultant products. The observed Mossbauer studies proved the ferromagnetic nature of nanoparticles (NPs) samples. The crystallite size (XRD) varies in a range of (23.30–35.12) nm. The direct optical energy band gap (E
g
) of all samples were calculated by Tauc plots where the E
g
values are found in a small range of 1.97–2.15 eV. The experimental evidences signify the promising use of newly prepared nano-hexaferrites in the development of materials in various industrial devices and far better than the conventional available hexaferrites materials.
14 citations