Magnetic Properties of Sm3+ Doped Zinc Phosphate Glass Containing Nickel Oxide Nanoparticles

2016 ◽  
Vol 846 ◽  
pp. 80-84
Author(s):  
Siti Amlah Mohamad Azmi ◽  
M.R. Sahar

Nickel nanoparticles are incorporated in Sm3+ doped zinc phosphate glass having a composition of 40ZnO-(58-x)P2O5-1Sm2O3-xNiO, with x = 0.0 and 2.0 mol% prepared by melt quenching technique. Sample characterizations are made by means of X-ray diffraction, transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). X-ray diffraction shows that the glass is in amorphous state. The transmission electron microscopic (TEM) image reveals the existence of Nickel nanoparticles having a particles size in the range of 5.5 – 21.8 nm. The magnetization M(H) curve reveals that the glass displays an anomalous hysteresis behavior at room temperature. It is observed that the initial curve of magnetization lies positively as a function of magnetic field under 1000 H (O.e).

2019 ◽  
Vol 290 ◽  
pp. 41-45
Author(s):  
Puzi Anigrahawati ◽  
M.R. Sahar ◽  
Sib Krishna Ghoshal

Erbium ions (Er3+) doped zinc phosphate glass system with varying contents of natural ferrite (Fe3O4) nanoparticles were prepared using melt quenching method. The glass is characterized by x-ray diffraction (XRD) and UV-VIS NIR spectrometer. It is observed that the amorphous nature of the glass is confirmed by x-ray diffraction. The absorption spectra of the glass are recorded in the UV-Visible in the range of 400-1600 nm. The UV-VIS NIR spectra reveal ten absorption peaks centered at 376, 406, 420, 486, 522, 546, 652, 798, 976 and 1534 nm, correspond to the transitions from the ground state 4I15/2 to higher 4I13/2, 4I11/2, 4I9/2, 4F9/2, 4S3/2, 2H11/2, 4F7/2, 4F3/2, 2H9/2, 4G11/2 levels, respectively. Effects of natural ferrite oxide nanoparticles on the absorption and emission properties of the synthesized glasses were analyzed via Judd-Ofelt (J-O) theory. The J-O intensity-parameters (W2, W4, W6) analysis demonstrate a significant increase of spectroscopic quality factors.Keywords: Fe3O4 NPs, Absorption, Judd-Ofelt.


2011 ◽  
Vol 80-81 ◽  
pp. 217-220 ◽  
Author(s):  
Xue Qing Yue ◽  
Hai Jun Fu ◽  
Da Jun Li

Graphite encapsulated nickel nanoparticles were prepared by ball milling andsubsequently annealing a mixture of expanded graphite with nickel powders. The products were characterized by transmission electron microscope and X-ray diffraction. The formation mechanism of the products was discussed. Results show that the products have a size range of 20-150 nm. The graphite and nickel in the products all exhibit a high crystallinity.


2004 ◽  
Vol 19 (10) ◽  
pp. 2905-2912 ◽  
Author(s):  
Tokeer Ahmad ◽  
Ashok K. Ganguli

Nanoparticles of barium orthotitanate (Ba2TiO4) was obtained using microemulsions (avoiding Ba-alkoxide). Powder x-ray diffraction studies of the powder after calcining at 800 °C resulted in a mixture of orthorhombic (70%) and monoclinic (30%) phases. The high-temperature orthorhombic form present at 800 °C was due to the small size of particles obtained by the reverse micellar route. Pure orthorhombic Ba2TiO4 was obtained on further sintering at 1000 °C with lattice parameters a = 6.101(2) Å, b =22.94(1) Å, c = 10.533(2) Å (space group, P21nb). The particle size obtained from x-ray line broadening studies and transmission electron microscopic studies was found to be 40–50 nm for the powder obtained after heating at 800 °C. Sintering at 1000 °C showed increase in grain size up to 150 nm. Our studies corroborate well with the presence of a martensitic transition in Ba2TiO4. The dielectric constant was found to be 40 for Ba2TiO4 (at 100 kHz) for samples sintered at 1000 °C. The dielectric loss obtained was low (0.06) at 100 kHz.


2010 ◽  
Vol 09 (05) ◽  
pp. 439-445
Author(s):  
DHIRAJ KUMAR ◽  
SUNIL KUMAR ◽  
H. S. BHATTI

In this paper, addition of aluminum in zinc oxide is incorporated using low-temperature chemical synthesis route. Aluminum ions help in crystallization of zinc oxide nanoparticles. Characterization of the synthesized nanoparticles of zinc oxide has been done using Transmission electron microscope (TEM), and X-ray diffraction (XRD) analysis, Energy-resolved photoluminescence (PL) spectra and Time-resolved laser-induced photoluminescence (TRPL) at room temperature. Transmission electron microscopic observations and X-Ray diffraction studies indicate highly crystalline nature and particle size of the order of 20 nm in ZnO:Al . Time-resolved laser-induced photoluminescence measurements have been done using pulsed nitrogen laser as an excitation source, operated at wavelength 337.1 nm and having high peak output power of 1 MW. The results show that at higher concentrations of Al doping in host ZnO phosphor, emission intensity is more by several orders of magnitude and lifetime shortening indicates that these nanoparticles are more efficient as compared with lower concentrations of dopant.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Manoj Pudukudy ◽  
Zahira Yaakob

α-Mn2O3 microspheres with high phase purity, crystallinity, and surface area were synthesized by the thermal decomposition of precipitated MnCO3 microspheres without the use of any structure directing agents and tedious reaction conditions. The prepared Mn2O3 microspheres were characterized by Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) and photoluminescence (PL) studies. The complete thermal transformation of MnCO3 to Mn2O3 was clearly shown by the FTIR and XRD analysis. The electron microscopic images clearly confirmed the microsphere-like morphology of the products with some structural deformation for the calcined Mn2O3 sample. The mesoporous texture generated from the interaggregation of subnanoparticles in the microstructures is visibly evident from the TEM and BET studies. Moreover, the Mn2O3 microstructures showed a moderate photocatalytic activity for the degradation of methylene blue dye pollutant under UV light irradiation, using air as the potential oxidizing agent.


2002 ◽  
Vol 01 (05n06) ◽  
pp. 477-481 ◽  
Author(s):  
LEE DON KEUN ◽  
YOUNG SOO KANG

Silver nanoclusters have been formed by thermal decomposition of Ag-oleate complex. Transmission electron microscopic (TEM) images of the particles showed two-dimensional assembly of particles with diameter of 10.5 nm. Energy-dispersive X-ray (EDX) spectrum and X-ray diffraction (XRD) peaks of the nanoclusters showed the highly crystalline nature of the silver structures. The decomposition of silver-oleate complex was analyzed by Thermo Gravimetric Analyzer (TGA) and the crystallization process was observed by XRD. The removal of the surfactant surrounding silver nanoclusters was measured by FT-IR and SEM images.


1990 ◽  
Vol 5 (9) ◽  
pp. 1871-1879 ◽  
Author(s):  
L. C. Chen ◽  
F. Spaepen ◽  
J. L. Robertson ◽  
S. C. Moss ◽  
K. Hiraga

Scanning and isothermal calorimetry, together with x-ray diffraction and high resolution transmission electron microscopy (TEM), have been used to characterize Al–Mn and Al–Mn–Si films sputtered onto substrates at 60 °C, 45 °C, and −100 °C. In the case of Al0.83Mn0.17, the monotonically decreasing isothermal calorimetric signal, characteristic of a grain growth process, has proved decisive in identifying the as-sputtered “amorphous” state as microquasicrystalline, with an average grain size of ∼ 20 Å, in agreement with an estimate of correlation range from the x-ray pattern. The TEM at 400 keV reveals well-defined atomic or lattice images in annealed films but only barely resolved grains (ordered clusters) in the as-sputtered films. The relation between the metallic glass and the microquasicrystalline state in these alloys is discussed.


1998 ◽  
Vol 547 ◽  
Author(s):  
L. Ledig ◽  
D. Hough ◽  
C.-G. Oertel ◽  
J. Eckert ◽  
W. Skrotzki

AbstractThe solid state reaction of YNi2B2C by mechanical alloying of elemental powders has been investigated by X-ray diffraction, transmission electron microscopy and susceptibility measurements. Depending on the ball milling parameters either nanocrystalline YNi2B2C or an amorphous phase can be produced. Crystallization of the amorphous phase by annealing at 893 K produces YNi2B2C as major and Ni2B as minor intermetallic compound. Superconductivity is only observed in the annealed state. However, the transition temperature is much lower than in arc-melted samples. This is discussed with respect to the nanocrystalline and amorphous state as well as deviations from stoichiometry produced by impurities introduced during milling.


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