scholarly journals Magnetic and microwave absorption properties of nickel ferrite (NixFe3-xO4) by HEM technique

2017 ◽  
Vol 13 (3) ◽  
Author(s):  
Yunasfi Yunas ◽  
Wisnu Ari Adi ◽  
Mashadi Mashadi ◽  
Putri Astari Rahmy
Keyword(s):  
Nickel Ferrite ◽  
Single Phase ◽  
Magnetic Measurement ◽  
High Energy ◽  
Infrared Analysis ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
Absorption Properties ◽  
Microwave Absorption Properties ◽  
Maximum Value

Nickel ferrite (NixFe3-xO4) have been synthesized using solid state reaction with composition (2x)NiO : (3-x)Fe2O3 (x = 0.5; 1.0; 1.5 dan 2.0) in mol in wt%. Mixing of this powder was milled with HEM (High Energy Milling) for 10 hours, and then sintered at 1000 °C for 3 h. X-ray diffraction pattern indicates that the all of samples are single phase in this stage. FTIR (Fourier transform infrared) analysis showed two absorption bands in the range of ~410 - ~600 cm-1 related to octahedral and tetrahedral sites. The magnetic measurement using vibrating sample magnetometer (VSM) shows that the sample exhibited a ferromagnetic behaviour with its coercivity value in the range of 164-217 Oe, and the maximum value wasshowed by x =1.5. VNA (Vector Network Analyzer) characterization shows the ability electromagnetic wave absorption with RL (reflection loss) value of -28 dB occurs at frequency of 10.98 GHz. It means that the Ni1.5Fe1.5O4 sample can absorb microwave about ~96 % at 10.98 GHz.

scholarly journals MAGNETIC AND MICROWAVE ABSORPTION PROPERTIES OF NEODYMIUM DOPED NICKEL FERRITE USING MILLING TECHNIQUE

2019 ◽  
Vol 81 (4) ◽  
Author(s):  
Yunasfi Yunasfi ◽  
Mashadi Mashadi ◽  
Ade Mulyawan
Keyword(s):  
Nickel Ferrite ◽  
Magnetic Measurement ◽  
Spinel Ferrite ◽  
Solid State Reaction Method ◽  
High Energy ◽  
Morphological Observation ◽  
Ferromagnetic Behavior ◽  
X Ray Diffraction ◽  
Diffraction Patterns ◽  
Compound Materials

Nickel ferrite doped by neodymium in the form of (Ni(1-x)NdxFe2O4) with (x =  0.0 ; 0.2 and 0.4) have been synthesized using solid state reaction method with milling technique from NiO, Nd2O3 and Fe2O3 powder. The mixture of those compound materials was milled using High Energy Milling (HEM) machine for 10 hours and then sintered at 1000 °C for 5 h. X-ray diffraction patterns showed that a single phase of spinel ferrite has been formed in all of the compositions. The result of morphological observation using Scanning Electron Microscope (SEM) exhibited a homogeneous structure has been formed with particle size about 200 nm. The magnetic measurement using vibrating sample magnetometer (VSM) showed that the sample exhibited a ferromagnetic behavior, where the Ms value decrease (around of 58.4 to 39.40 emu/g) and value of Hc increased (around of 116-170 Oe) along with the addition of the Nd3+ ion (x values) content. While the ability of microwaves absorption measured by using Vector Network Analyzer (VNA) indicates that the maximum value of Reflection Loss (RL) obtained at the composition of x = 0.4 up to -29 dB at a frequency of 10.81 GHz. It means the Ni0,6Nd0,4Fe2O4 sample can absorb microwave up to ~ 96.5% at a frequency of 10.81 GHz.

scholarly journals Complex Permittivity and Microwave Absorption Properties of OPEFB Fiber–Polycaprolactone Composites Filled with Recycled Hematite (α-Fe2O3) Nanoparticles

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 918 ◽  
Author(s):  
Ebenezer Ekow Mensah ◽  
Zulkifly Abbas ◽  
Raba’ah Syahidah Azis ◽  
Nor Azowa Ibrahim ◽  
Ahmad Mamoun Khamis
Keyword(s):  
Microwave Absorption ◽  
Complex Permittivity ◽  
Microstructural Analysis ◽  
High Energy ◽  
Fe2o3 Nanoparticles ◽  
X Ray Diffraction ◽  
Absorption Properties ◽  
Microwave Absorption Properties ◽  
Transmission Electron ◽  
Line Measurement

Recycled hematite (α-Fe2O3) nanoparticles with enhanced complex permittivity properties have been incorporated as a filler in a polycaprolactone (PCL) matrix reinforced with oil palm empty fruit bunch (OPEFB) fiber for microwave absorption applications. The complex permittivity values were improved by reducing the particle sizes to the nano scale via high-energy ball milling for 12 h. A total of 5–20 wt.% recycled α-Fe2O3/OPEFB/PCL nanocomposites were examined for their complex permittivity and microwave absorption properties via the open ended coaxial (OEC) technique and the transmission/reflection line measurement using a microstrip connected to a two-port vector network analyzer. The microstructural analysis of the samples included X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR). At 1 GHz, the real (ε′) and imaginary (ε″) parts of complex permittivity of recycled α-Fe2O3 particles, respectively, increased from 7.88 to 12.75 and 0.14 to 0.40 when the particle size was reduced from 1.73 μm to 16.2 nm. A minimum reflection loss of −24.2 dB was achieved by the 20 wt.% nanocomposite at 2.4 GHz. Recycled α-Fe2O3 nanoparticles are effective fillers for microwave absorbing polymer-based composites in 1–4 GHz range applications.

Synthesis, Characterization, and Microwave Absorption Properties of SrFe12O19 Ferrites and FeNi3 Nanoplatelets Composites

2010 ◽  
Vol 148-149 ◽  
pp. 893-896 ◽  
Author(s):  
Ze Yang Zhang ◽  
Xiang Xuan Liu ◽  
You Peng Wu
Keyword(s):  
Electron Microscopy ◽  
Microwave Absorption ◽  
Composite Coatings ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Absorption Properties ◽  
Filling Fraction ◽  
Microwave Absorption Properties ◽  
Phase Reduction ◽  
Transmission Electron

M-typical SrFe12O19 ferrites and FeNi3 nanoplatelets were successfully prepared by the sol-gel method and solution phase reduction method, respectively. The crystalline and morphology of particles were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The composite coatings with SrFe12O19 ferrites and FeNi3 nanoplatelets in polyvinylchloride matrix were prepared. The microwave absorption properties of these coatings were investigated in 2-18GHz frequency range. The results showed that the M-typical SrFe12O19 ferrites and FeNi3 nanoplatelets were obtained and they presented irregular sheet shapes. With the increase of the coating thickness, the absorbing peak value moves to the lower frequency. The absorbing peak values of the wave increase along with the increasing of the content of FeNi3 nanoplatelets filling fraction. When 40% SrFe12O19 ferrites is doped with 20% mass fraction FeNi3 nanoplatelets to prepare composite with 1.5mm thickness, the maximum reflection loss is -24.8 dB at 7.9GHz and the -10 dB bandwidth reaches 3.2GHz.

Prepared and Microwave-Absorption Properties of BN Coated Ni Nanocapsules

2010 ◽  
Vol 663-665 ◽  
pp. 1252-1255 ◽  
Author(s):  
Gui Mei Shi ◽  
Shu Lian ◽  
Ge Song ◽  
Jin Bing Zhang
Keyword(s):  
Reflection Loss ◽  
Electromagnetic Properties ◽  
Mechanochemical Reaction ◽  
Network Analyzer ◽  
Absorber Thickness ◽  
X Ray Diffraction ◽  
Absorption Properties ◽  
Microwave Absorption Properties ◽  
X Ray ◽  
Transmission Electron

BN coated Ni nanocapsules were prepared by arc evaporating Ni-B amorphous alloy powders synthesized by a mechanochemical reaction, and their microstructure, surface component as well as electromagnetic properties (2-18 GHz) were investigated by means of high-resolution transmission electron microscopy, X-ray diffraction , photoluminescence spectra (PL) and a network analyzer, respectively. The reflection loss R (dB) of the nanocapsules less than -20 dB was obtained in the frequency range of 4.3-18 GHz for an absorber thickness of 1.4-6 mm. An optimal reflection loss of -32.0 dB was reached at 13 GHz with an absorber thickness of 2 mm. The microwave absorptive mechanisms of BN-coated Ni nanocapsule absorbent were discussed.

Investigation of Ti Doping on the Structural, Optical and Magnetic Properties of ZnO Nanoparticles

2021 ◽  
Author(s):  
Raji P ◽  
K Balachandra Kumar
Keyword(s):  
Hexagonal Wurtzite Structure ◽  
Xrd Analysis ◽  
Infrared Analysis ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Co Precipitation ◽  
Ti Doping

Abstract Ti - doped ZnO (TixZn1-xO x= 0.00, 0.05, 0.10, 0.15) nanoparticles have been synthesized through co - precipitation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), UV-Visible spectroscopy, and Vibrating Sample Magnetometer (VSM) have been used to characterize the samples. X-Ray Diffraction (XRD) analysis manifested the hexagonal wurtzite structure. The crystallite size decreased from 37 ​nm to 29 ​nm as dopant concentration is increased. Fourier transform infrared analysis showed the absorption bands of ZnO, with few within the intensities. SEM investigation showed the irregular shape and agglomeration of the particles. Ti, Zn, and O composition were determined from EDX analysis and confirmed the purity of the samples.PL spectra showed a near band edge emission and visible emission.Vibrating sample magnetometer (VSM) demonstrated pure and doped samples exhibited ferromagnetism behavior at room temperature.

La and Co doping effects on magnetoresistance of double perovskite Sr2FeMoO6

2015 ◽  
Vol 29 (20) ◽  
pp. 1550140 ◽  
Author(s):  
SongChol Ri ◽  
GwangSu Kim
Keyword(s):  
Magnetic Field ◽  
Doping Concentration ◽  
Magnetic Measurements ◽  
Double Perovskite ◽  
High Energy ◽  
X Ray Diffraction ◽  
Co Doping ◽  
Maximum Value ◽  
Doping Effects ◽  
Low Magnetic Field

Double perovskite Sr 2 FeMoO 6 (SFMO) with composition of Sr 2-x La x Fe 1-y Co y MoO 6(x = 0, 0.1, 0.2, 0.3, 0.4, 0.5 at.%; y = 0, 0.05, 0.1, 0.2, 0.3, 0.5, 0.9 at.%) was synthesized by high energy ball milling and sintering. The sintered samples were investigated by means of X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and magnetic measurements. XRD results show that all the samples have single phase double perovskite structure. EDS spectrum confirmed that the actual composition of prepared samples is in agreement with nominal ones. With the increase of doping concentration of La, the magnetization decreases, whereas Curie temperature increases in SFMO. And with doping concentration of La, the magnetoresistance (MR) ratio with a low magnetic field of 480 kA/m increases, has its maximum value as 5% for x = 0.3 at 293 K. The degree of antisite disorder decreases with Co 2+ doping, and therefore results in increase of MR ratio. At room temperature, the MR ratio with a considerable low magnetic field for x = 0.3, y = 0.1 has maximum value as 6.5%.

Structure and Microwave Absorption Properties of Ho-Fe-Si Alloys

2018 ◽  
Vol 914 ◽  
pp. 117-123 ◽  
Author(s):  
Jia Liang Luo ◽  
Shun Kang Pan ◽  
Li Chun Cheng ◽  
Pei Hao Lin ◽  
Yu He ◽  
...  
Keyword(s):  
Ball Milling ◽  
Matching Condition ◽  
Peak Frequency ◽  
High Energy ◽  
X Ray Diffraction ◽  
Absorption Properties ◽  
Arc Melting ◽  
Microwave Absorbing Materials ◽  
Milling Method ◽  
Si Content

The Ho2Fe17-xSix (x=0.0, 0.1, 0.2, 0.3) alloys were prepared by arc melting and high energy ball milling method. The influence of the Si substitution on phase structure, morphology and electromagnetic parameters were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and vector network analyzer (VNA), respectively. The results show that the Ho-Fe-Si particles are flaky after the ball milling. The minimum absorption peak frequency shifts towards a lower frequency region with the increasing of Si content. The minimum RL of Ho2Fe16.7Si0.3 reaches-42.96 dB at 9.76 GHz, and the frequency bandwidth of R<-10 dB reaches about 2.64 GHz with the best matching condition d=1.6 mm. The reflection loss with the thickness ranging of 1.2-3.0 mm could reach-10 dB, which indicates the particles be considered as the promising microwave absorbing materials with a good absorption properties.

MICROWAVE ABSORPTION BEHAVIOR OF MESOPOROUS TRANSITION METAL OXIDE TEMPLATED FROM SBA-15 AND KIT-6

2014 ◽  
Vol 28 (10) ◽  
pp. 1450037 ◽  
Author(s):  
HONGJING WU ◽  
LIUDING WANG ◽  
YIMING WANG
Keyword(s):  
Electron Microscope ◽  
Microwave Absorption ◽  
Absorption Characteristic ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Hard Template ◽  
Absorption Properties ◽  
Microwave Absorption Properties ◽  
X Ray ◽  
Transmission Electron

In this paper, we have synthesized meso-oxides (i.e., Co 3 O 4 and NiO ) by using mesoporous silica as hard template. The microstructures and chemical compositions of the corresponding meso-oxides were characterized by the Transmission electron microscope-selected area electron diffusion (TEM-SAED), X-ray diffraction (XRD), scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS), respectively. And, their electromagnetic and microwave absorption properties were investigated in the frequency range of 2–18 GHz. The results indicate that meso-oxide templated from KIT-6 (i.e., meso-K– Co / Ni ) exhibit a dual absorption characteristic compared with those using SBA-15 as hard template. This phenomenon suggests that meso-oxides templated from SBA-15 and KIT-6 can exhibit different microwave absorption behaviors due to their respective microstructures.

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