STRUCTURAL, SURFACE MORPHOLOGICAL AND MAGNETIC STUDIES OF Zn1−xFexS (x=0.00–0.10) DILUTED MAGNETIC SEMICONDUCTORS GROWN BY CO-PRECIPITATION METHOD

We have fabricated Zn[Formula: see text]FexS ([Formula: see text], 0.02, 0.04, 0.06, 0.08 and 0.10) diluted magnetic semiconductors using co-precipitation method. X-ray diffraction patterns depict that Zn[Formula: see text]FexS appears as a dominant phase with cubic zinc blende structure and nanoscale crystallite size. In addition, a secondary phase of rhombohedral ZnS also appears; however, no additional phase arises that primarily belongs to Fe dopant. Using Debye–Scherrer relation, the crystallite size is found to be in the range of 20–27[Formula: see text]nm, which is in good agreement with the crystallite size calculated using the Williamson–Hall (WH) plot method. The appearance of secondary phase provoked to study the residual strain using Stokes–Wilson equation, which is nearly consistent to that observed using WH plot method. The surface morphology, revealed using scanning electron microscopy, depicts non-uniform surface structure with a variety of grains and void dimensions. Hysteresis loops measured for Zn[Formula: see text]FexS at room temperature (RT) illustrate a paramagnetic behavior at higher fields; however, small ferromagnetic behavior is evident due to the small openings of the measured hysteresis loops around the origin. The measured RT ferromagnetism reveals the potential spintronic device applications of the studied diluted magnetic semiconductors.

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Effect of M-Type Hexaferrites on Mechanical and Magnetic Properties of Hydroxyapatite Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.751.611 ◽

2017 ◽

Vol 751 ◽

pp. 611-616

Author(s):

Rewadee Wongmaneerung

Keyword(s):

Magnetic Properties ◽

Magnetic Hysteresis ◽

Hysteresis Loops ◽

Barium Hexaferrite ◽

Precipitation Method ◽

Strontium Hexaferrite ◽

Ferromagnetic Behavior ◽

Hydroxyapatite Ceramics ◽

Xrd Patterns ◽

Co Precipitation

The overall aim of this study is to establish the inter-relationships between phase formations, mechanical properties and magnetic properties of the novel ceramic in hydroxyapatite system for biomaterial applications. First, barium hexaferrite and strontium hexaferrite powders were prepared as M-type hexaferrite phases. Hydroxyapatite was prepared from cockle shells via co-precipitation method. After that, a combination between hydroxyapatite+barium hexaferrite and hydroxyapatite+strontium hexaferrite was mixed together then shaping and sintering at 1200 °C for 2 h. The sintered samples were characterized phase formation, mechanical and magnetic properties by using X-ray diffraction (XRD), Universal testing and VSM measurements, respectively. XRD patterns for all samples showed a combination between hydroxyapatite and hexaferrite phases. Compressive strength of all samples tends to increase with increasing of the amount of hexaferrite phases due to densification mechanism. However, the increasing of these values, it appears that there is no difference in the statistical significant. For magnetic properties, the coexistence of barium hexaferrite and strontium hexaferrite phases reveals magnetic hysteresis loops, showing the change from diamagnetic to ferromagnetic behavior.

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Fabrication and Characterisation of Diluted Magnetic Semiconductors Thin Films Using Ion Beams

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.2869 ◽

2012 ◽

Vol 706-709 ◽

pp. 2869-2873

Author(s):

M. Ionescu ◽

P. Photongkam ◽

R. Siegele ◽

A. Deslantes ◽

S. Li ◽

...

Keyword(s):

Magnetic Properties ◽

Room Temperature ◽

Diluted Magnetic Semiconductors ◽

Depth Distribution ◽

Magnetic Semiconductors ◽

Ion Irradiation ◽

Research Effort ◽

Critical Parameters ◽

Ferromagnetic Behavior ◽

Diluted Magnetic

The intrinsic n-type (II-VI) semiconductor ZnO may become ferromagnetic at room temperature, by small additions of magnetic ions, resulting in what is called a Diluted Magnetic Semiconductors (DMS). The potential application of DMS in spintronic devices of is driving the research effort to dope magnetic elements into this semiconductors with a depth distribution as uniform as possible. The doping levels and the depth distribution of dopants are critical parameters for the magnetic properties of this material and the possible clustering of dopants can play a significant negative role in its macroscopic magnetic properties. Thin ZnO (0001) films of between 100nm and 500nm, grown on c-Al2O3 by MOCVD were implanted with Co, Eu and Co+Eu by ion irradiation at low energies. In order to improve the depth distribution of dopants, the ion implantation was carried out through a number of appropriately chosen range foils. The results show an increase in the level of dopant homogeneity throughout the entire thickness of the film, and a ferromagnetic behavior above room temperature for Zn0.96Co0.04O, Zn0.96Eu0.04O and Zn0.92Co0.04Eu0.04O.

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THE INFLUENCE OF NANOMETRIC SIZE ON VARIOUS PROPERTIES OF NANOCRYSTALLINE Zn0.9Ni0.1O DILUTED MAGNETIC SEMICONDUCTORS

International Journal of Nanoscience ◽

10.1142/s0219581x11008733 ◽

2011 ◽

Vol 10 (04n05) ◽

pp. 949-954

Author(s):

K. SRINIVAS ◽

P. VENUGOPAL REDDY

Keyword(s):

Crystallite Size ◽

Room Temperature ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Surface Condition ◽

Spectral Studies ◽

Magnetic Clusters ◽

Optical Absorbance ◽

Diluted Magnetic ◽

Nanometric Size

With a view to understand the influence of nanometric size on various properties of nanocrystalline Zn0.9Ni0.1O diluted magnetic semiconductors, a systematic investigation has been undertaken. Samples were prepared for the first time by hydrazine assisted polyol method and are post annealed in air at different temperatures to vary the crystallite size. From the Rietveld refinement of XRD data, the isotropic crystallite size values are found to be in the range, 15–42 nm. Further, the phase analysis of Rietveld refined XRD data, FT-IR and optical absorbance spectral studies revealed that all the samples are having hexagonal wurzite structure without any detectable impurity phases. From AFM topography studies, it has been found that the surface condition of the grains and their distributions clearly depend on the nano size of the materials. From the PL measurements, the local defects of the materials were explored. From magnetization studies which were carried out by using VSM and MFM techniques, it has been found that all the samples are found to exhibit a clear ferromagnetic hysteresis behavior at room temperature without any magnetic clusters. Finally, electrical properties were also undertaken at room temperature to understand the variation of magnetic behavior as a function of nanometric size of these materials.

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Room temperature ferromagnetism in single-phase Zn1−x Mn x S diluted magnetic semiconductors fabricated by co-precipitation technique

Applied Physics A ◽

10.1007/s00339-017-0975-5 ◽

2017 ◽

Vol 123 (5) ◽

Cited By ~ 14

Author(s):

M. Hassan ◽

S. Younas ◽

F. Sher ◽

S. S. Husain ◽

S. Riaz ◽

...

Keyword(s):

Room Temperature ◽

Diluted Magnetic Semiconductors ◽

Single Phase ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Precipitation Technique ◽

Diluted Magnetic ◽

Co Precipitation

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Influence of Lithium Content on Performance of Layered Li1+z[Ni0.45Mn0.45Co0.1]1-zO2 in Lithium Ion Batteries

MRS Proceedings ◽

10.1557/proc-0972-aa06-11 ◽

2006 ◽

Vol 972 ◽

Cited By ~ 1

Author(s):

Jie Xiao ◽

Natasha A. Chernova ◽

M. Stanley Whittingham

Keyword(s):

Lithium Ion Batteries ◽

Single Phase ◽

Hysteresis Loops ◽

Lithium Ion ◽

Precipitation Method ◽

Lithium Content ◽

Magnetic Studies ◽

Cation Disorder ◽

Metal Ratio ◽

Co Precipitation

AbstractLi1+z[Ni0.45Mn0.45Co0.1]1-zO2(0.8≤1+z≤1.2) has been synthesized by the co-precipitation method. It was found that 5% excess lithium must be added to obtain the desired composition. XRD results show that an apparent single-phase structure appears except for the lowest lithium content. The layered character of the structure increases with increasing lithium content and Rietveld refinement reveals that cation disorder decreases rapidly as more lithium is added. This conclusion is further confirmed by magnetic studies in which only Li0.8[Ni0.45Mn0.45Co0.1]1.2O2 and Li0.9(Ni0.45Mn0.45Co0.1)1.1O2 show magnetization hysteresis loops. The electrochemical behavior of this series of samples is compared to figure out the best lithium to transition metal ratio.

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Effect of Oxygen Vacancy on Structural, Optical and Magnetic Behavior of Tin Oxide Nanoparticles

International Journal of Nanoscience ◽

10.1142/s0219581x1850045x ◽

2019 ◽

Vol 19 (01) ◽

pp. 1850045

Author(s):

M. Dinesh ◽

R. Ravindran ◽

V. Rukkumani ◽

K. Srinivasan ◽

M. Saravanakumar

Keyword(s):

Diffraction Method ◽

Magnetic Behavior ◽

Molar Concentration ◽

Precipitation Method ◽

Ferromagnetic Behavior ◽

Magnetic Studies ◽

X Ray ◽

Chloride Dihydrate ◽

Metal Doped ◽

Co Precipitation

Nanocrystalline SnO2powder has been successfully synthesized by using tin(II) chloride dihydrate (SnCl[Formula: see text]H2O), distilled water and liquid ammonia by the simple chemical co-precipitation method at room temperature using different SnCl[Formula: see text]H2O molar concentration of 0.3[Formula: see text]M, 0.4[Formula: see text]M and 0.5[Formula: see text]M. The structural properties of the prepared SnO2and transition metal doped SnO2nanoparticles has been studied using X-ray diffraction method and scanning electron microscope. The composition of the powders has been analyzed using energy dispersive X-ray analysis. The XRD pattern of the SnO2nanoparticles indicates the formation of single-phase rutile tetragonal structure. The grain size is found to be in the range of 3–7[Formula: see text]nm and is found to increase with increasing SnCl2molar concentration. The absorption spectra revealed that the bandgap decreased from 3.74[Formula: see text]eV to 3.59[Formula: see text]eV with increasing SnCl2molar concentration. The photoluminescence spectra of SnO2nanoparticles showed a visible broad luminescence band in the region of 385–430[Formula: see text]nm. The magnetic studies have been carried out using the hysteresis loop obtained from a vibrating sample magnetometer. The SnO2samples using 0.3 and 0.4 SnCl2molar concentration exhibited ferromagnetic behavior whereas the SnO2sample prepared using 0.5[Formula: see text]M SnCl[Formula: see text]H2O exhibited paramagnetic nature.

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ZnO NEEDLE-LIKE STRUCTURES: SYNTHESIS AND CHARACTERIZATION

Kongunadu Research Journal ◽

10.26524/krj88 ◽

2015 ◽

Vol 2 (2) ◽

pp. 13-15

Author(s):

Sugapriya S ◽

Lakshmi S ◽

Senthil kumaran C.K ◽

Chandarshekar B ◽

Ranjithkumar R

Keyword(s):

Crystallite Size ◽

Hexagonal Phase ◽

Secondary Phase ◽

Precipitation Method ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Co Precipitation

We report in this paper, the structural and I-V properties of ZnO nano needle-like structure synthesized by Co-precipitation method. X-ray diffraction (XRD) result shows that the ZnO nano needle-like structure with hexagonal phase and no secondary phase was observed. The crystallite size has been calculated by Scherrer’s equation which was found to be in the range 40-60 nm. SEM images reveal that ZnO nano needle-like structure has the length of ~5.5 µm and base of ~5 µm are consistent with the results from SEM investigations. I-V characteristics have been carried out to study the conducting behaviour of the prepared ZnO nano needle-like structures.

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