scholarly journals The Structural and Magnetic Properties of the Double Rearth Elements La1−xNdxFeO3 Nanoparticles

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Nguyen Thi Thuy ◽  
Bach Thanh Cong ◽  
Dang Le Minh
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Magnetic Property ◽  
Room Temperature ◽  
Sol Gel ◽  
Ferromagnetic Behavior ◽  
Orthorhombic Structure ◽  
Nanosized Powders ◽  
Structural And Magnetic Properties ◽  
20 Nm

The double rearth elements La1−xNdxFeO3 (0≤x≤0.5) nanosized powders with orthorhombic structure were prepared by sol-gel method. The particle size of the La1−xNdxFeO3 powder is about 20 nm. The doping of the second rearth element in the A position of the compound ABO3 influenced the crystalline structure and magnetic property of the samples. The M(H) dependence shows that the nanosized La1−xNdxFeO3 samples exhibit ferromagnetic behavior in the room temperature and the M(H) curves are well fitted by Langevin functions.

scholarly journals Structural and Magnetic Properties of Mn Doped BiFeO3 Nanomaterials

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
V. Srinivas ◽  
A. T. Raghavender ◽  
K. Vijaya Kumar
Keyword(s):  
Magnetic Properties ◽  
Doping Concentration ◽  
Structural Changes ◽  
Sol Gel ◽  
Rietveld Analysis ◽  
Ferromagnetic Behavior ◽  
Structural Formation ◽  
Mn Doping ◽  
Structural And Magnetic Properties ◽  
Mn Doped

Nanocrystalline Bi1-xMnxFeO3  (0≤x≤0.3) materials were synthesized using sol-gel technique. The structural and magnetic properties were investigated in detail. Rietveld analysis from XRD revealed the structural formation of BiFeO3. As the Mn doping concentration was increased, the structure of BiFeO3 changed from rhombohedral to tetragonal. All the M-H loops showed the ferromagnetic behavior in the prepared samples. Magnetization was observed to enhance as the Mn doping concentration was increased. The enhanced magnetization may be due to the collapse of the space modulated spin structure as observed from the structural changes.

Hydrothermal Synthesis of CoFe2O4 Nanoparticles and their Magnetic Properties

2013 ◽  
Vol 821-822 ◽  
pp. 1358-1361 ◽  
Author(s):  
Fan Zhang ◽  
Rui Liang Su ◽  
Li Zhi Shi ◽  
Yang Liu ◽  
Yan Na Chen ◽  
...  
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Spinel Ferrite ◽  
Synthesis Method ◽  
Ferrite Nanoparticles ◽  
Particle Sizes ◽  
Naoh Solution ◽  
20 Nm

CoFe2O4 (CFO) nanoparticles was synthesized by a simple hydrothermal method using NaOH solution as a mineralizer at 200 °C for 4 h. It was found that CFO particle sizes decreased firstly and then increased with the increasing of NaOH concentration, and had a minumum value about 10-20 nm when selected 4 mol/L NaOH solution, indicating the NaOH concentration played an important role in controlling the particle size of CFO powders. The room temperature magnetic measurements showed that the saturation magnetization value was 48 emu/g, which is less than the bulk value. The synthesis method is possible to be a general approach for the preparation of other spinel ferrite nanoparticles.

STRUCTURAL AND MAGNETIC PROPERTIES OF THE THIN FILM OF COBALT NITRIDE

2014 ◽  
Vol 21 (06) ◽  
pp. 1450081 ◽  
Author(s):  
ZOHRA NAZIR KAYANI ◽  
SAIRA RIAZ ◽  
SHAHZAD NASEEM
Keyword(s):  
Magnetic Properties ◽  
Sol Gel ◽  
Magnetic Memory ◽  
Vibrating Sample Magnetometer ◽  
Orthorhombic Structure ◽  
X Ray ◽  
Cu Substrates ◽  
Gel Technique ◽  
Structural And Magnetic Properties ◽  
Memory Applications

Cobalt nitride has been prepared and studied for magnetic memory applications. Sol–gel technique is used to prepare thin films of cobalt nitride. The films were deposited onto Cu substrates by spin coating at 3000 rpm for 30 s. The films were then air dried and heated at 300°C for 120 min. As-deposited and heated samples were characterized for their structural and magnetic properties using X-ray diffractometer (XRD) and vibrating sample magnetometer (VSM) techniques. The grain size was in the range of 22.7–30.10 nm. Their surface was studied by scanning electron microscopy (SEM). Orthorhombic structure can be seen in SEM micrographs. This orthorhombic structure is also confirmed by XRD.

scholarly journals The Structural and Magnetic Properties of Gadolinium Doped CoFe2O4Nanoferrites

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Qing Lin ◽  
Jinpei Lin ◽  
Yun He ◽  
Ruijun Wang ◽  
Jianghui Dong
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Crystallite Size ◽  
Room Temperature ◽  
Cobalt Ferrite ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Lattice Parameter ◽  
Cubic Phase ◽  
Structural And Magnetic Properties

Gadolinium substituted cobalt ferrite CoGdxFe2−xO4(x= 0, 0.04, 0.08) powders have been prepared by a sol-gel autocombustion method. XRD results indicate the production of a single cubic phase of ferrites. The lattice parameter increases and the average crystallite size decreases with the substitution of Gd3+ions. SEM shows that the ferrite powers are nanoparticles. Room temperature Mössbauer spectra of CoGdxFe22−xO4are two normal Zeeman-split sextets, which display ferrimagnetic behavior. The saturation magnetization decreases and the coercivity increases by the Gd3+ions.

Structure and Magnetic Properties of (Al, Co) Co-Doped ZnO Thin Films

2012 ◽  
Vol 531-532 ◽  
pp. 299-302
Author(s):  
Ping Cao ◽  
Yue Bai
Keyword(s):  
Magnetic Properties ◽  
Sol Gel ◽  
Ferromagnetic Behavior ◽  
X Ray Diffraction ◽  
Al Doping ◽  
X Ray ◽  
Free Carriers ◽  
Structural And Magnetic Properties ◽  
Co Doped ◽  
Main Factor

In this study, Zn0.99Co0.01Al0.015O thin film has been prepared by sol-gel method. The structural and magnetic properties of the sample were investigated. X-ray diffraction spectroscopy analyses indicate that the Co and Al codoping can not disturb the structure of ZnO. No additional peaks are observed in the Zn0.99Co0.01AlxO and Al3+ and Co2+ substitute for Zn2+ without changing the wurtzite structure. The resistance measurements confirm that Al ions increase the free carriers concentration. Based on the above experiments we think the ferromagnetic behavior of the sample could not originate from Co nanoclusters. The presence of free carriers and localized d spins is a prerequisite for the appearance of ferromagnetism. As the result, the carriers generated by Al doping is considered a main factor to induce the ferromagnetic phenomenon.

Structure and Magnetism of Nanocrystalline KδMnO2

1999 ◽  
Vol 602 ◽  
Author(s):  
R.M. Stroud ◽  
E. Carpenter ◽  
V.M. Browning ◽  
J.W. Long ◽  
K.E. Swider ◽  
...  
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Sol Gel ◽  
Blocking Temperature ◽  
X Ray Diffraction ◽  
Surface Layers ◽  
Mixed Valency ◽  
Transmission Electron ◽  
Typical Particle ◽  
20 Nm

AbstractThe structure and magnetic properties of sol-gel-synthesized, nanocrystalline KσMnO2 were investigated. The nanoparticles were determined by x-ray diffraction and high-resolution transmission electron microscopy to be single-crystal rods of the cryptomelane phase of MnO2, with a typical particle size of 6 nm × 20 nm. The field and temperature dependence of the magnetization indicates superparamagnetic behavior, with a blocking temperature of 15K. The dependence of the magnetic properties on particle size, surface layers and mixed valency is discussed.

Structural and Magnetic Properties of Cr- and Fe-Doped CeO2 Nanoparticles Prepared by Sol-Gel Method

2016 ◽  
Vol 848 ◽  
pp. 682-687 ◽  
Author(s):  
Sheng Hong Yang ◽  
Yue Li Zhang
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Magnetic Measurements ◽  
Physical Property Measurement System ◽  
Sol Gel ◽  
Physical Property ◽  
Ferromagnetic Behavior ◽  
Sem Images ◽  
Uniform Size ◽  
Structural And Magnetic Properties

A study of the structural and magnetic properties of Cr-and Fe-doped CeO2 nanoparticles produced by the sol–gel-based method was undertaken. The crystal structure and phase, morphology, and magnetic properties of the sample were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy (Raman) and physical property measurement system (PPMS). XRD and Raman studied showed that Cr-and Fe-doped did not change CeO2 original cubic fluorite crystal structure, and no ferromagnetic secondary phase was observed. SEM images showed that Cr-and Fe-doped CeO2 nanoparticles were spherical, uniform size, and good dispersion. The particle size was about 20 nm. The magnetic measurements showed that the Cr-and Fe-doped CeO2 nanoparticles presented ferromagnetic behavior at 10 and 300 K, indicating the Curie temperature was above room temperature. The magnetization diminished with the increase of the temperature. The saturation magnetization and coercivity of Fe-doped CeO2 nanoparticles were higher than that of Cr-doped CeO2 nanoparticles. Combined with the results of XRD and Raman, the ferromagnetic behavior can be attributed to the intrinsic properties of Cr-and Fe-doped CeO2 nanostructures.

Effect of pH on the Structural and Magnetic Properties of Magnetite Nanoparticles Synthesised by Co-Precipitation

2011 ◽  
Vol 324 ◽  
pp. 129-132 ◽  
Author(s):  
Wegdan Ramadan ◽  
Marwa Kareem ◽  
Béatrice Hannoyer ◽  
Shanta Saha
Keyword(s):  
Particle Size ◽  
Raman Spectroscopy ◽  
Magnetic Properties ◽  
Magnetite Nanoparticles ◽  
Room Temperature ◽  
Ph Value ◽  
Magnetite Fe3o4 ◽  
Aqueous Method ◽  
Structural And Magnetic Properties ◽  
Co Precipitation

Magnetite, Fe3O4, nanoparticles were synthesized using co-precipitation aqueous method at room temperature and at different pH, from 8 to 12.5. The pH value was found to influence greatly the resulting phases and has no significant effect on the particle size. In all cases, magnetite was found to be the main phase but the contribution of Goethite phase was identified clearly with the increase in pH. Significant reduction in saturation magnetization was evident. Structural and magnetic properties of the nanoparticles were examined using; XRD, TEM, Raman Spectroscopy and SQUID.

Photoluminescence and Magnetic Properties of Undoped and (Mn, Co) co-doped ZnO Nanoparticles

2020 ◽  
Vol 16 (4) ◽  
pp. 655-666
Author(s):  
Mona Rekaby
Keyword(s):  
Magnetic Properties ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Structural Defects ◽  
Ferromagnetic Behavior ◽  
Secondary Phases ◽  
Antiferromagnetic Ordering ◽  
Doped Zno ◽  
Co Doped

Objective: The influence of Manganese (Mn2+) and Cobalt (Co2+) ions doping on the optical and magnetic properties of ZnO nanoparticles was studied. Methods: Nanoparticle samples of type ZnO, Zn0.97Mn0.03O, Zn0.96Mn0.03Co0.01O, Zn0.95Mn0.03 Co0.02O, Zn0.93Mn0.03Co0.04O, and Zn0.91Mn0.03Co0.06O were synthesized using the wet chemical coprecipitation method. Results: X-ray powder diffraction (XRD) patterns revealed that the prepared samples exhibited a single phase of hexagonal wurtzite structure without any existence of secondary phases. Transmission electron microscope (TEM) images clarified that Co doping at high concentrations has the ability to alter the morphologies of the samples from spherical shaped nanoparticles (NPS) to nanorods (NRs) shaped particles. The different vibrational modes of the prepared samples were analyzed through Fourier transform infrared (FTIR) measurements. The optical characteristics and structural defects of the samples were studied through Photoluminescence (PL) spectroscopy. PL results clarified that Mn2+ and Co2+ doping quenched the recombination of electron-hole pairs and enhanced the number of point defects relative to the undoped ZnO sample. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer (VSM). (Mn, Co) co-doped ZnO samples exhibited a ferromagnetic behavior coupled with paramagnetic and weak diamagnetic contributions. Conclusion: Mn2+ and Co2+ doping enhanced the room temperature Ferromagnetic (RTFM) behavior of ZnO. In addition, the signature for antiferromagnetic ordering between the Co ions was revealed. Moreover, a strong correlation between the magnetic and optical behavior of the (Mn, Co) co-doped ZnO was analyzed.

Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

2012 ◽  
Vol 501 ◽  
pp. 236-241 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah ◽  
Ramadan E. Shaiboub
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Garnet Phase ◽  
Sol Gel Process ◽  
Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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