Influence of CoO Phase on Structural, Magnetic and Electrical Properties of La0.7Ca0.3MnO3 and La0.7Sr0.3MnO3

The composites of (1-x)La0.7Ca0.3MnO3/xCoO and (1-x)La0.7Sr0.3MnO3/xCoO (x =0 ~ 0.09) were fabricated by conventional solid state reaction method, and their electrical transport and magnetoresistance (MR%) properties were investigated by physical property measurement system (PPMS). The result of x-ray diffraction (XRD) and scanning electronic microscopy (SEM) indicated that no new phase appeared in the composites except manganites matrix and CoO phases. CoO is mainly distributed at the grain boundaries and surfaces of the matrix. The resistivity LCMO and LSMO based composites were measured in the range 90-320K and 90-400K, respectively. The applied magnetic field is 0T and 0.5T. The observed variation of MR with varying Ca and Sr concentration has been qualitatively investigated.

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Single crystal growth and magnetic properties of Co-doped ZnNb2O6

Modern Physics Letters B ◽

10.1142/s0217984919502749 ◽

2019 ◽

Vol 33 (23) ◽

pp. 1950274

Author(s):

Ying Liu ◽

Dapeng Xu ◽

Huamin Yu ◽

Tian Cui ◽

Liang Li

Keyword(s):

Magnetic Properties ◽

Single Crystals ◽

Photoelectron Spectroscopy ◽

Physical Property Measurement System ◽

Physical Property ◽

X Ray Diffraction ◽

Zone Method ◽

X Ray ◽

Structure Formula ◽

Property Measurement

The columbite structure [Formula: see text] single crystals have been successfully grown by using the optical floating zone method. The as-grown crystals are characterized by X-ray diffraction (XRD), Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS). All these analyses show that the doping Co ions do not disturb the structure of columbite [Formula: see text] and some [Formula: see text] ions are substituted by transition metal [Formula: see text] ions without any other impurities. The magnetic properties of as-grown [Formula: see text] crystals have been investigated using Physical Property Measurement System (PPMS). The effective magnetic moment of [Formula: see text] crystals is [Formula: see text], indicating that [Formula: see text] ions present in [Formula: see text] single crystals are in mixed HS and LS states. The ferromagnetic, antiferromagnetic and paramagnetic characters of as-grown crystals are also discussed.

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Synthesis and Properties of Nanosized Stoichiometric Cobalt Ferrite Spinel

Materials ◽

10.3390/ma11071241 ◽

2018 ◽

Vol 11 (7) ◽

pp. 1241 ◽

Cited By ~ 9

Author(s):

Vilém Bartůněk ◽

David Sedmidubský ◽

Štěpán Huber ◽

Marie Švecová ◽

Pavel Ulbrich ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Physical Property Measurement System ◽

Physical Property ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Property Measurement ◽

Scherrer Formula ◽

Ferrite Spinel

Nanoparticles with controllable sizes of ferrite spinel CoFe2O4 were formed by thermal treatment of cobalt-iron glycerolate. Thermal behavior during the heating was studied by differential thermal analysis combined with thermogravimetry. The precursor, as well as the prepared nanoparticles, were analyzed by a broad spectrum of analytic techniques (X-Ray photoelectron spectroscopy (XPS), X-Ray diffraction (XRD), Energy dispersive spectroscopy (EDS), Atomic absorption spectroscopy (AAS), Scanning electron microscopy (SEM), and Raman spectroscopy). The particle size of nanoparticles was obtained from Transmission electron microscopy and also calculated using Scherrer formula. A vibrating sample magnetometer (VSM) in a Physical Property Measurement System was used to analyze the magnetic properties of nanoparticles.

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ELECTRICAL TRANSPORT PROPERTIES AND MAGNETORESISTANCE OF (La0.7Ca0.3MnO3)1-x/(CuFe2O4)x COMPOSITES

Surface Review and Letters ◽

10.1142/s0218625x10013667 ◽

2010 ◽

Vol 17 (01) ◽

pp. 33-38 ◽

Cited By ~ 4

Author(s):

YOUNG JOO KIM ◽

SHALENDRA KUMAR ◽

YONG JUN SEO ◽

JIHO CHANG ◽

CHAN GYU LEE ◽

...

Keyword(s):

Electrical Transport ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Electrical Transport Properties ◽

Conventional Solid State Reaction ◽

Low Field ◽

Spin Polarized ◽

Spin Dependent Scattering ◽

Mr Effect ◽

New Phase

The ( La 0.7 Ca 0.3 MnO 3)1-x/( CuFe 2O4)x (x = 0–0.15) composites were prepared by conventional solid state reaction method. We have investigated the structural, magnetic and electrical properties of ( La 0.7 Ca 0.3 MnO 3)1-x/( CuFe 2 O 4)x composites using X-ray diffraction (XRD), scanning electron microscopy, field cooled DC magnetization and magnetoresistance (MR) measurements. The resistance measured as a function of temperature demonstrates that pure LCMO samples display metal to semiconductor transition. On the other hand, all the LCMO/CFO composites samples clearly present the electrical behavior of insulator/semiconductor. It indicates that resistivity of the samples increase systemically with the increase of CFO content. The MR was measured in the presence of 0.5 T field. At low temperatures, it is clearly observed that the MR effect is enhanced with x = 0.03 of CFO composition. In summary, the spin-polarized tunneling and the spin-dependent scattering may be helpful to the improved low-field magnetoresistance (LFMR) effect. These phenomena can be explained by the segregation of a new phase related to CFO at the grain boundaries or surfaces of the LCMO grains.

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Effect of Sintering Temperature on Structural and Electrical Transport Properties of (La0.7Ca0.3MnO3)0.97/(ZnO)0.03 Composite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.378.202 ◽

2013 ◽

Vol 378 ◽

pp. 202-208

Author(s):

Ho Je Cho ◽

Seung Rok Lee ◽

M.S. Anwar ◽

Hang Joo Ko ◽

Bon Heun Koo

Keyword(s):

Electrical Transport ◽

Sintering Temperature ◽

X Ray Diffraction ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Electrical Transport Properties ◽

Conventional Solid State Reaction ◽

X Ray ◽

Electrical And Magnetic Properties ◽

New Phase

The composites of (La0.7Ca0.3MnO3)0.97/(ZnO)0.03were fabricated with having different sintering temperature by conventional solid state reaction methods, and their magnetoresistance (MR) properties and electrical transport were investigated. The result of scanning electronic microscopy (SEM) and X-ray diffraction (XRD) indicated that no new phase appeared in the composites except LCMO and ZnO phases. specially, SEM results show that with increment of sintering temperature, the grain size of La0.7Ca0.3MnO3also increases, which plays a key on electrical and magnetic properties of the (La0.7Ca0.3MnO3)0.97/(ZnO)0.03composites. The electrical transport and magnetic was measured over a temperature range of 90 320K. tables etc. (2012H1B8A2026212), (NIPA-2013-H0301-13-2009)

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Synthesis of Monodispersed Fe3O4 Magnetite Nanoparticles by Ethylene Glycol Solvothermal Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.2276 ◽

2013 ◽

Vol 634-638 ◽

pp. 2276-2279 ◽

Cited By ~ 2

Author(s):

Gang Xu ◽

Min Zhang ◽

Ping Ou ◽

Yi Zhang ◽

Gao Rong Han

Keyword(s):

Ethylene Glycol ◽

Magnetite Nanoparticles ◽

Solvothermal Method ◽

Physical Property Measurement System ◽

Physical Property ◽

X Ray Diffraction ◽

Ferromagnetic Property ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Property Measurement

Monodispersed Fe3O4 magnetite nanoparticles were successfully synthesized via a simple solvothermal method, in which Fe(NO3)3•9H2O was used as the starting materials, KOH as the mineralizer, and ethylene glycol (en) as the solvent. X-ray diffraction (XRD) and selected area electron diffraction (SAED) were employed to characterize the phase composition, transmission electron microscope (TEM) to observe the morphology and the particle size, and physical property measurement system (PPMS) to investigate the magnetic property of the synthesized powders, respectively. The synthesized Fe3O4 magnetite nanoparticles are of 50-100nm in size, and of notable ferromagnetic property. The saturation magnetization, remanent magnetization, and coercive field are 68.8emu•g-1, 12.9emu•g-1, 138.5Oe, respectively. Based on the experimental resuts, the formation mechanism and the well monodispersed reason of the solvothersized Fe3O4 nanoparticles are discussed.

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The structural, magnetic and electrical transport properties of perovskite La0.67Sr0.33Mn1−x(VMn)xO3: The B-sites vacancies as a rapier

Modern Physics Letters B ◽

10.1142/s0217984921504157 ◽

2021 ◽

pp. 2150415

Author(s):

Denghui Ji ◽

Bin Zhang ◽

Yong Yang ◽

Shuling Wang ◽

Yingdi Liu ◽

...

Keyword(s):

Electrical Transport ◽

Double Exchange ◽

Secondary Phase ◽

Solid State Reaction Method ◽

Photoelectron Spectra ◽

Small Range ◽

Electrical Transport Properties ◽

Conventional Solid State Reaction ◽

Double Exchange Interaction ◽

X Ray

The polycrystalline samples of manganites perovskite [Formula: see text] with B-sites vacancies were synthesized using the conventional solid-state reaction method. The results based on the X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) analyses show that the samples with [Formula: see text] have a secondary phase of lanthanum oxides. It indicates there is a maximum vacancy content at the B-sites with [Formula: see text]. By X-ray Photoelectron Spectra (XPS), the ionicities of oxygen were determined to be 0.762, 0.842, and 0.886, corresponding to [Formula: see text], 0.03, and 0.05, respectively. The B-sites vacancy plays an important role in magnetic performances: (i) B-sites vacancy changes the contents and the average cant angle of Mn cations, and makes the specific saturation magnetization at 100 K and 300 K increase, and then decrease rapidly. (ii) The Curie temperature changes in a small range from 363.93 K to 366.00 K, resulting from both the double exchange interaction increasing and the double exchange path destroyed by the vacancies. (iii) The magnetoresistance (MR) at room temperature achieves 6.97% in the [Formula: see text] sample, whose value is larger than that of [Formula: see text] sample.

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Dielectric and Raman studies of Ba0.06(Na1/2Bi1/2)0.94TiO3–NaNbO3 ceramics

Materials Science-Poland ◽

10.1515/msp-2016-0041 ◽

2016 ◽

Vol 34 (2) ◽

pp. 437-445 ◽

Cited By ~ 6

Author(s):

Sumit K. Roy ◽

S. Chaudhuri ◽

R.K. Kotnala ◽

D.K. Singh ◽

B.P. Singh ◽

...

Keyword(s):

Single Phase ◽

Solid State Reaction Method ◽

Lead Free ◽

Orthorhombic Symmetry ◽

Dielectric Studies ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

New Phase ◽

Diffusivity Parameter

AbstractIn this work the X-ray diffraction, scanning electron microscopy, Raman and dielectric studies of lead free perovskite (1 – x)Ba0.06(Na1/2Bi1/2)0.94TiO3–xNaNbO3 (0 ⩽ x ⩽ 1.0) ceramics, prepared using a standard solid state reaction method, were investigated. X-ray diffraction studies of all the ceramics suggested the formation of single phase with crystal structure transforming from rhombohedral-tetragonal to orthorhombic symmetry with the increase in NaNbO3 content. Raman spectra also confirmed the formation of solid solution without any new phase. Dielectric studies showed that the phase transition is of diffusive character and diffusivity parameter decreases with increasing NaNbO3 content. The compositional fluctuation was considered to be the main cause of diffusivity.

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Temperature Dependence on Dielectric Response of La0.7Ba0.3Mn0.4Ti0.6O3 Ceramic

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1107.45 ◽

2015 ◽

Vol 1107 ◽

pp. 45-52

Author(s):

Aaliyawani Ezzerin Sinin ◽

Walter Charles Primus ◽

Abdul Halim Shaari ◽

Zainal Abidin Talib ◽

Sinin Hamdan

Keyword(s):

Dielectric Properties ◽

Temperature Dependence ◽

Low Frequency ◽

Sintered Sample ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Conventional Solid State Reaction ◽

Low Frequencies ◽

X Ray ◽

Lcr Meter

Ceramic sample of La0.70Ba0.30Mn0.40Ti0.60O3 oxide has been prepared by the conventional solid-state reaction method. The sintered sample was characterized by using x-ray diffraction (XRD) and low frequency LCR meter. XRD result shows that the sample has a cubic structure with the existence of impurity phase. The dielectric properties of La0.70Ba0.30Mn0.40Ti0.60O3 measured from room temperature to 200°C shows that the dielectric permittivity is temperature dependence with strong dispersion at low frequencies. A circuit model based on the universal capacitor response function is also being used to represent the dielectric properties of the sample.

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MULTIFERROIC MATERIALS Bi1-xSmxFeO3: A STUDY OF RAMAN AND ABSORPTION SPECTROSCOPIES

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863510005248 ◽

2010 ◽

Vol 19 (02) ◽

pp. 247-254 ◽

Cited By ~ 4

Author(s):

NGUYEN VAN MINH ◽

DAO VIET THANG

Keyword(s):

Lattice Dynamics ◽

Optical Band Gap ◽

Solid State Reaction Method ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Conventional Solid State Reaction ◽

X Ray ◽

Lattice Constants ◽

Raman Measurement

Multiferroic Bi 1-x Sm x FeO 3(x = 0.00, 0.05, 0.1, 0.15, 0.2) ceramics were prepared by conventional solid state reaction method. X-ray diffraction measurement was carried out to characterize the crystal structure and to detect the impurities existing in these ceramics. The substitution of rare earth Sm for Bi was found to decrease the impurity phase in BiFeO 3 ceramics. There is strong evidence that both lattice constants a and c of the unit cell become smaller as the Sm 3+ content is increased. The effect of introducing Sm 3+ is shown to decrease the optical band gap for doped sample Bi 1-x Sm x FeO 3. Additionally, the temperature-dependent Raman measurement performed for the lattice dynamics study of Bi 1-x Sm x FeO 3 samples reveals a strong band centered at around 1000–1300 cm-1 which is associated with the resonant enhancement of two-phonon Raman scattering in the multiferroic Bi 1-x Sm x FeO 3 samples. This two-phonon signal is shown to broaden with increasing x. The Raman spectra at low wavenumbers are suggested to be related with magnon in this system.

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