MAGNETIC PROPERTIES OF Co-FERRITE AND SiO2-DOPED Co-FERRITE THIN FILMS AND POWDERS BY SOL–GEL

2004 ◽  
Vol 03 (04n05) ◽  
pp. 463-470
Author(s):  
Y. C. WANG ◽  
J. DING ◽  
B. H. LIU ◽  
Y. SHI

Thin films and powders of Co -ferrite and SiO 2-doped Co -ferrite were fabricated via the sol–gel method. The structural and magnetic properties of the films and powders were investigated with X-Ray Diffractometer (XRD), Vibrating Sample Magnetometer (VSM), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). VSM measurements showed an enhancement of coercivity by SiO 2-doping for Co -ferrite powders and thin films (coercivity of 3.5 kOe in SiO 2-doped thin films). XRD and SEM investigations revealed a nanostructure of the thin films. Low surface roughness was observed in our AFM study.

2012 ◽  
Vol 501 ◽  
pp. 236-241 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah ◽  
Ramadan E. Shaiboub

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.


Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4962
Author(s):  
Pawel Pietrusiewicz ◽  
Marcin Nabiałek ◽  
Bartłomiej Jeż

This paper presents the results of an investigation into rapidly quenched Fe-based alloys with the chemical formula: Fe61Co10B20W1Y8−xPtx (where x = 3, 4, 5). In these alloys, a small quantity of Pt was added, and the Y content was reduced concurrently. Samples of the aforementioned alloys were injection-cast in the form of plates with the dimensions: 0.5 mm × 10 mm × 10 mm. The resulting structure was examined using X-ray diffractometry (XRD), Mössbauer spectroscopy and scanning electron microscopy (SEM). The results of the structural research reveal that, with a small addition of Pt, areas rich in Pt and Y are created—in which Fe-Pt and Pt-Y compounds, with different crystallographic systems, are formed. It has also been shown that an increase in Pt content, at the expense of Y, contributed to the formation of fewer crystalline phases, i.e., it allowed a material with a more homogeneous structure to be obtained. Magnetic properties of the Fe61Co10B20W1Y8−xPtx (where x = 3, 4, 5) alloy samples were tested using a vibrating sample magnetometer (VSM). The magnetic properties of the investigated materials revealed that the saturation magnetisation increased with increasing Pt content, at the expense of Y. This effect is due to the occurrence of different proportions of crystalline magnetic phases within the volume of each alloy.


2012 ◽  
Vol 151 ◽  
pp. 314-318
Author(s):  
Ching Fang Tseng ◽  
Cheng Hsing Hsu ◽  
Chun Hung Lai

This paper describes microstructure characteristics of MgAl2O4 thin films were deposited by sol-gel method with various preheating temperatures and annealing temperatures. Particular attention will be paid to the effects of a thermal treatment in air ambient on the physical properties. The annealed films were characterized using X-ray diffraction. The surface morphologies of treatment film were examined by scanning electron microscopy and atomic force microscopy. At a preheating temperature of 300oC and an annealing temperature of 700oC, the MgAl2O4 films with 9 μm thickness possess a dielectric constant of 9 at 1 kHz and a dissipation factor of 0.18 at 1 kHz.


2008 ◽  
Vol 8 (4) ◽  
pp. 1757-1761 ◽  
Author(s):  
Ajeet Kaushik ◽  
Jitendra Kumar ◽  
M. K. Tiwari ◽  
R. Khan ◽  
B. D. Malhotra ◽  
...  

Polyaniline (PANI)–ZnO nanocomposite thin film has been successfully fabricated on glass substrates by using vacuum deposition technique. The as-grown PANI–ZnO nanocomposite thin films have been characterized using X-ray diffraction, Scanning Electron Microscopy, Atomic Force Microscopy, UV-visible spectrophotometer and Fourier Transform Infrared (FTIR) spectroscopy, respectively. X-ray diffraction of as-grown film shows the reflection of ZnO nanoparticles along with a broad peak of PANI. The surface morphology of nanocomposite films has been investigated using scanning electron microscopy and atomic force microscopy. The hypsochromic shift of the UV absorption band corresponding to π–π* transition in polymeric chain of PANI and a band at 504 cm –1 due to ZnO nanoparticles has been observed in the FTIR spectra. The hydrogen bonding between the imine group of PANI and ZnO nanoparticle has been confirmed from the presence of the absorbance band at 1151 cm–1 in the FTIR spectra of the nanocomposite thin films.


2014 ◽  
Vol 21 (06) ◽  
pp. 1450081 ◽  
Author(s):  
ZOHRA NAZIR KAYANI ◽  
SAIRA RIAZ ◽  
SHAHZAD NASEEM

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.


2013 ◽  
Vol 744 ◽  
pp. 315-318
Author(s):  
Wei Rao ◽  
Ding Guo Li ◽  
Hong Chun Yan

Cobalt ferrite (CoFe2O4) thin films have been prepared on Si (001) substrates, with different calcined temperatures (Tcal=400°C~800°C). The films structure was studied by X-ray diffraction (XRD) and their surface was examined by scanning electron microscopy (SEM). The magnetic properties were measured with a vibrating sample magnetometer (VSM). For low calcined temperatures, the films presented a mixture of a CoFe2O4phase, with the cubic spinel structure, and cobalt and iron antiferromagnet oxides with CoO and FeO stoichiometries. As the calcined temperature increased, the CoO and FeO relative content strongly decreased, so that for Tcal=800°Cthe films were composed mainly by polycrystalline CoFe2O4. The magnetic hysteresis cycles measured in the films were horizontally shifted due to an exchange coupling field originated by the presence of the antiferromagnetic phases.


2018 ◽  
Author(s):  
Kseniia Lushcheva

SrRuO3 is an itinerant ferromagnet with a Curie temperature of ~160K. There has been a sharp increase in scientific interest towards this material and its intriguing features, such as its magnetic anisotropy, and anomalous transport properties which are incompatible with Drude model. In this study, several thin films of strontium ruthenate were grown and characterised in quality and quantity, employing techniques such as X-ray diffraction and atomic force microscopy. The results are presented and described as crystallographic and topographic findings; finally, based on the findings, adjustments and further study are proposed.


2015 ◽  
Vol 814 ◽  
pp. 39-43 ◽  
Author(s):  
Lei Lei Chen ◽  
Hong Mei Deng ◽  
Ke Zhi Zhang ◽  
Ling Huang ◽  
Jian Liu ◽  
...  

Cu2MnSnS4 thin film was successfully prepared by a sol-gel technique on soda lime glass substrate from metal salts and thiourea. The structural and morphological properties of the fabricated film were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and atomic force microscopy. The combination of the X-ray diffraction results and Raman spectroscopy reveal that this obtained layer is composed by Cu2MnSnS4 phase and has a stannite structure with preferential orientation along the (112) direction. The scanning electron microscopy and atomic force microscopy results show that the synthesized thin film is smooth and compact without any visible cracks or pores. The band gap of the Cu2MnSnS4 thin film is about 1.29 eV determined by the UV-vis-NIR absorption spectra measurement, which indicates it has potential applications in solar cells.


2005 ◽  
Vol 475-479 ◽  
pp. 3693-3696
Author(s):  
Wen Xiu Cheng ◽  
Ai Li Ding ◽  
Ping Sun Qiu

Amorphous and crystalline (Zr0.8,Sn0.2)TiO4 (ZST) thin films deposited on Si(100) substrates have been prepared by a sol-gel process. The crystal structure and surface morphologies of the thin films have been studied by X-ray diffraction and atomic force microscopy. The crystalline ZST films on Si(100) substrata with a (111) orientation The refractive index n and extinction coefficient k of the amorphous and crystalline thin films were obtained by spectroscopy ellipsometry as a function of phone energy in the range from 0.7 to 5.4 eV. The absorption edges for amorphous and crystalline ZST are 3.83 and 3.51eV of indirect–transition type respectively.


2017 ◽  
Vol 07 (04) ◽  
pp. 1750029 ◽  
Author(s):  
Jing Zhang ◽  
Peng Shi ◽  
Mingmin Zhu ◽  
Ming Liu ◽  
Wei Ren ◽  
...  

We report the preparation of epitaxial La[Formula: see text]Sr[Formula: see text]MnO3 thin films grown on (001)-oriented 0.72Pb(Mg[Formula: see text]Nb[Formula: see text]O3-0.28PbTiO3 substrates by the sol–gel technique. The phase structure, magnetic properties and magnetoresistance of the samples are investigated by using high solution X-ray diffraction, atomic force microscopy, physical property measurement system, respectively. The La[Formula: see text]Sr[Formula: see text]MnO3 thin films display a well-defined hysteresis loop and typical ferromagnetism behavior at lower temperature. High magnetoresistance at 5[Formula: see text]T of 42% appears at 227[Formula: see text]K for La[Formula: see text]Sr[Formula: see text]MnO3 thin film.


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