Improved electrical properties of cadmium substituted cobalt ferrites nano-particles for microwave application

The synergistic effects of zinc oxide (ZnO) Micro/Nano particles simultaneously filled in low-density polyethylene (LDPE) on the space charge characteristics and electrical properties has been investigated by melt blending micro-scale and nanoscale ZnO additive particles into LDPE matrix to prepare Micro-ZnO, Nano-ZnO, and Micro-Nano ZnO/LDPE composites. The morphological structures of composite samples are characterized by Polarizing Light Microscopy (PLM), and the space charge accumulations and insulation performances are correlated in the analyses with Pulse Electronic Acoustic (PEA), DC breakdown field strength, and conductance tests. It is indicated that both the micro and nano ZnO fillers can introduce plenty of heterogeneous nuclei into the LDPE matrix so as to impede the LDPE spherocrystal growth and regularize the crystalline grains in neatly-arranged morphology. By filling microparticles together with nanoparticles of ZnO additives, the space charge accumulations are significantly inhibited under an applied DC voltage and the minimum initial residual charges with the slowest charge decaying rate have been achieved after an electrode short connection. While the micro-nano ZnO/LDPE composites acquire the lowest conductivity, the breakdown strengths of the ZnO/LDPE nanocomposite and micro-nano composite are, respectively, 13.7% and 3.4% higher than that of the neat LDPE material.

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Enhanced electrical properties in Nd doped cobalt ferrite nano-particles

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/146/1/012027 ◽

2016 ◽

Vol 146 ◽

pp. 012027 ◽

Cited By ~ 3

Author(s):

S. Abbas ◽

A. Munir ◽

F. Zahra ◽

M. A. Rehman

Keyword(s):

Electrical Properties ◽

Cobalt Ferrite ◽

Nano Particles

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Synthesis and Thermoelectric Studies in Cr Doped Cobalt Ferrites Nano Particles

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.510-511.171 ◽

2012 ◽

Vol 510-511 ◽

pp. 171-176 ◽

Cited By ~ 3

Author(s):

M. Anis-ur-Rehman ◽

Mariam Ansari ◽

Zeb Un Nisa Mughal ◽

M.S. Awan ◽

Ashari Maqsood

Keyword(s):

Seebeck Coefficient ◽

Thermoelectric Power ◽

Room Temperature ◽

Nano Particles ◽

Power Measurement ◽

Cobalt Ferrites ◽

Before And After ◽

Crystallite Sizes ◽

Xrd Patterns ◽

Co Precipitation

Samples of Cr doped cobalt ferrite were prepared by co-precipitation route. These particles were characterized by X-ray diffraction (XRD) at room temperature. The structural properties were observed before and after sintering. The FCC spinel structure was confirmed by XRD patterns of the samples. The crystallite sizes lie in the range of 37-60 nm. DC electrical properties as a function composition were measured. Scanning electron microscopy was used in order to investigate the surface morphology of the prepared samples. The system for thermoelectric power measurement was designed, developed and calibrated in the laboratory. The room temperature thermoelectric power was measured for the prepared samples. The magnitude of Seebeck coefficient depends on the composition and resistivity of the samples. The obtained values of Seebeck coefficient for CoFe2O4are in good agreement to the reported values. Determined values of Seebeck coefficient for other studied compositions are an addition to the literature.

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Electrical properties of sub-100nm Cu films deposited by electroless plating on amino-terminated silicon oxide activated with Au nano-particles

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2009.08.028 ◽

2009 ◽

Vol 204 (4) ◽

pp. 520-524 ◽

Cited By ~ 13

Author(s):

A. Inberg ◽

E. Glickman ◽

T. Asher ◽

N. Fishelson ◽

Y. Shacham-Diamand

Keyword(s):

Electrical Properties ◽

Electroless Plating ◽

Silicon Oxide ◽

Nano Particles ◽

Cu Films ◽

Au Nano Particles

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Processing Effect of Injection Molded Nanoparticle/Polymer Composites on their Resistivity

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.2531 ◽

2011 ◽

Vol 314-316 ◽

pp. 2531-2538

Author(s):

Hai Hong Wu ◽

Yong Feng Cheng ◽

Ai Yun Jiang ◽

Bao Feng Zhang

Keyword(s):

Electrical Properties ◽

Polymer Composites ◽

Injection Pressure ◽

Nano Particles ◽

High Resistivity ◽

Packing Pressure ◽

High Injection Pressure ◽

Injection Molded ◽

Skin Zone ◽

The Relationship

In order to improve the application of nano-particles/polymer composite, we investigated the relationship between microstructures and electrical properties on injection molded composites made from carbon black(CB) particles mixed with polypropylene(PP). Standard tensile specimens were injected under different processing conditions, after which, the specimens were cut off along the surface to observe the microstructures at different positions of the moldings. The microstructures were observed with Scanning Electrical Microscope(SEM), and electrical properties were measured by using a two-terminal standard resistor under DC condition at room temperature. The results showed that CB nano-particles may form the best conductive path under the higher packing pressure combined higher injection pressure. If packing pressure is low, the resistivities at the skin zone loaded by high injection pressure are smaller than low injection pressure, but the resistivities increase at the sub-skin zone. We found that the sub-skin zone is a high resistivity district which would expand with higher injection pressure matched lower packing pressure. Contrast to the injection molded polymer whose microstructural orientation is stronger at the sub-skin zones, injection molded CB particles/polymer composites develop strong oriented microstructures at the core zones in stead of the skin or sub-skin zones due to CB particles’ migration.

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Electrical properties of ZnO Nano-particles embedded in polyimide

Journal of Electronic Materials ◽

10.1007/s11664-006-0091-3 ◽

2006 ◽

Vol 35 (4) ◽

pp. 512-515 ◽

Cited By ~ 6

Author(s):

E. K. Kim ◽

J. H. Kim ◽

H. K. Noh ◽

Y. H. Kim

Keyword(s):

Electrical Properties ◽

Nano Particles

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Crystal Chemistry, Rietveld Analysis, Structural and Electrical Properties of Cobalt-Erbium Nano-Ferrites

10.5772/intechopen.98864 ◽

2021 ◽

Author(s):

Edapalli Sumalatha ◽

Dachepalli Ravinder ◽

Nyathani Maramu ◽

Shubha ◽

Butreddy Ravinder Reddy ◽

...

Keyword(s):

Particle Size ◽

Electrical Resistivity ◽

Electrical Properties ◽

Crystallite Size ◽

Rietveld Analysis ◽

Tem Analysis ◽

Lattice Volume ◽

Edax Analysis ◽

Cobalt Ferrites ◽

Structural Variables

Synthesis of Cobalt-Erbium nano-ferrites with formulation CoErxFe2-xO4 (x = 0, 0.005, 0.010, 0.015, 0.020, 0.025, and 0.030) using technique of citrate-gel auto-combustion was done. Characterization of prepared powders was done by using XRD, EDAX, FESEM, AFM and FTIR Spectroscopy, DC resistivity properties respectively. XRD Rietveld Analysis, SEM, TEM and EDAX analysis were taken up in studying spectral, structural, magnetic and electrical properties. XRD pattern of CEF nano particles confirm single phase cubic spinal structure. The structural variables given by lattice constant (a), lattice volume (v), average crystallite size (D) and X-ray density(dx), Bulk density (d), porosity (p), percentage of pore space (P%), surface area (s), strain (ε), dislocation density (δ), along with ionic radii, bond length and hoping length were calculated. SEM and TEM results reveal homogeneous nature of particles accompanied by clusters having no impurity pickup. TEM analysis gives information about particle size of nanocrystalline ferrite while EDAX analysis confirm elemental composition. Emergence of two arch shaped frequency bands (ν1 and ν2) that represent vibrations at tetrahedral site (A) and octahedral site(B) was indicated by spectra of FTIR. The samples electrical resistivity (DC) was measured between 30°C -600°C with Two probe method. XRD Rietveld analysis confirm crystallite size lying between 20.84 nm–14.40 nm while SEM analysis indicate formation of agglomerates and TEM analysis indicate particle size ranging between 24 nm–16 nm. DC Electrical measurements indicate continuous decrease in resistivity with increasing temperature while increasing doping decreases curie temperature. The Magnetic parameters such as Saturation magnetization (Ms), Remanent magnetization (Mr), Coercivity (Hc) and Squareness ratio (R = Mr/Ms), Magnetic moment (nB) were altered by doping of Er+3 content in the increasing order (x = 0.00 to 0.030). The increasing erbium content decreases magnetization thus converting the sample into soft magnetic material. Observations indicated strong dependence of magnetic properties on Erbium substitution and coercivity varies in accordance with anisotropy constant. Due to the presence of magnetic dipole Erbium substituted cobalt ferrites can be used in electromagnetic applications. The present study investigates the effect of different compositions of Er3+ replaced for Fe on structural properties and electrical resistivity of cobalt ferrites.

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Enhancement of Viscoelastic and Electrical Properties of Magnetorheological Elastomers with Nanosized Ni-Mg Cobalt-Ferrites as Fillers

Materials ◽

10.3390/ma12213531 ◽

2019 ◽

Vol 12 (21) ◽

pp. 3531 ◽

Cited By ~ 2

Author(s):

Siti Aishah Abdul Aziz ◽

Saiful Amri Mazlan ◽

U Ubaidillah ◽

Muhammad Kashfi Shabdin ◽

Nurul Azhani Yunus ◽

...

Keyword(s):

Electrical Properties ◽

Electrical Resistance ◽

Current Flow ◽

Flexible Structures ◽

High Concentration ◽

Magnetorheological Elastomers ◽

Conductivity Property ◽

Cobalt Ferrites ◽

The Magnetic Field ◽

Very High

Carbon-based particles, such as graphite and graphene, have been widely used as a filler in magnetorheological elastomer (MRE) fabrication in order to obtain electrical properties of the material. However, these kinds of fillers normally require a very high concentration of particles to enhance the conductivity property. Therefore, in this study, the nanosized Ni-Mg cobalt ferrite is introduced as a filler to soften MRE and, at the same time, improve magnetic, rheological, and conductivity properties. Three types of MRE samples without and with different compositions of Mg, namely Co0.5Ni0.2Mg0.3Fe2O4 (A1) and Co0.5Ni0.1Mg0.4Fe2O4 (A2), are fabricated. The characterization related to the micrograph, magnetic, and rheological properties of the MRE samples are analyzed using scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and the rheometer. Meanwhile, the effect of the nanosized Ni-Mg cobalt ferrites on the electrical resistance property is investigated and compared with the different Mg compositions. It is shown that the storage modulus of the MRE sample with the nanosized Ni-Mg cobalt ferrites is 43% higher than that of the MRE sample without the nanomaterials. In addition, it is demonstrated that MREs with the nanosized Ni-Mg cobalt ferrites exhibit relatively low electrical resistance at the on-state as compared to the off-state condition, because MRE with a higher Mg composition shows lower electrical resistance when higher current flow occurs through the materials. This salient property of the proposed MRE can be effectively and potentially used as an actuator to control the viscoelastic property of the magnetic field or sensors to measure the strain of the flexible structures by the electrical resistance signal.

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