Synthesis Behavior of La0.7Ca0.3MnO3 by Hydrothermal Method

2007 ◽  
Vol 26-28 ◽  
pp. 703-706
Author(s):  
Hung Su Im ◽  
Sang M. Lee ◽  
Chan Gyu Lee ◽  
Bon Heun Koo ◽  
Jung Bum Yoon ◽  
...  

We indicated synthesization of LCMO by hydrothermal reaction. The results of transmission electron microscopy revealed that the LCMO particles had wide range in size and various in shapes. The LCMO particles had a perovskite-type crystal structure with some other phases. Magnetic property was measured by physical property measurement system. Their crystallinity and magnetization tended to increased with increasing reaction time.

Materials ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1241 ◽  
Author(s):  
Vilém Bartůněk ◽  
David Sedmidubský ◽  
Štěpán Huber ◽  
Marie Švecová ◽  
Pavel Ulbrich ◽  
...  

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.


2013 ◽  
Vol 634-638 ◽  
pp. 2276-2279 ◽  
Author(s):  
Gang Xu ◽  
Min Zhang ◽  
Ping Ou ◽  
Yi Zhang ◽  
Gao Rong Han

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.


2013 ◽  
Vol 331 ◽  
pp. 522-526
Author(s):  
Jiang Wang ◽  
Jian Li ◽  
You Wen Wang

When the self-made with Teflon lined with stainless steel reaction kettle is used to produce PbTiO3 nanowires with the adoption of hydrothermal reaction , PbTiO3 nanowires with new structure can be made when Pb/Ti equals 2.2. Observed through the Transmission Electron Microscopy (TEM), the bending feature of the PbTiO3 nanowires can be observed for several times when X-ray diffraction (XRD) and Electron Backscattered Diffraction (EBSD) are used to analyse and test the crystal structure of the nanowires. The result of the study shows that the degree of the bending of the PbTiO3 nanowires varies with the intensity of the electron beam from the Transmission Electron Microscopy, and its process can be reversible.


Author(s):  
F.-R. Chen ◽  
T. L. Lee ◽  
L. J. Chen

YSi2-x thin films were grown by depositing the yttrium metal thin films on (111)Si substrate followed by a rapid thermal annealing (RTA) at 450 to 1100°C. The x value of the YSi2-x films ranges from 0 to 0.3. The (0001) plane of the YSi2-x films have an ideal zero lattice mismatch relative to (111)Si surface lattice. The YSi2 has the hexagonal AlB2 crystal structure. The orientation relationship with Si was determined from the diffraction pattern shown in figure 1(a) to be and . The diffraction pattern in figure 1(a) was taken from a specimen annealed at 500°C for 15 second. As the annealing temperature was increased to 600°C, superlattice diffraction spots appear at position as seen in figure 1(b) which may be due to vacancy ordering in the YSi2-x films. The ordered vacancies in YSi2-x form a mesh in Si plane suggested by a LEED experiment.


2015 ◽  
Vol 748 ◽  
pp. 93-96
Author(s):  
Cheng Mei Liu ◽  
Yu Xia Zhao ◽  
Jin Dong ◽  
Lu Hai Li ◽  
Yen Wei ◽  
...  

Using iron-oleate complex as a precursor, oleic acid as a stabilizer and 1-octadecene as a reductant, uniform-sized and highly monodisperse iron oxide nanoparitcles with different diameters were successfully synthesized via solvothermal method by changing reaction time. Transmission electron microscope (TEM), thermo-gravimetric analysis (TGA), fourier transform infrared spectroscopy (FT-IR), physical property measurement system (PPMS) and dynamic light scattering (DLS) was used to characterize obtained iron oxide nanoparticles. These results indicated that iron oxide nanoparitcles with the diameter ranging from 4 to 8 nm can be controllably synthesized.


2014 ◽  
Vol 28 (06) ◽  
pp. 1450045 ◽  
Author(s):  
Arbab Mohammad Toufiq ◽  
Fengping Wang ◽  
Qurat-ul-Ain Javed ◽  
Yan Li

In this paper, single crystalline 1D tetragonal MnO 2 pen-type nanorods were synthesized by varying the dwell time through a facile hydrothermal route at a reaction temperature of 250°C. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies showed that the diameter of MnO 2 nanorods decreases from 460 nm to 250 nm with the increase in hydrothermal reaction time from 5 h to 15 h. Field-emission scanning electron microscopy (FESEM) and TEM studies revealed the evolution of improved surface morphology of MnO 2 nanorods that are prepared with longer hydrothermal reaction time. The magnetic properties of the products were evaluated using vibrating sample magnetometer (VSM) at room temperature, which showed that the as-prepared samples exhibit weak ferromagnetic behavior. The effect of diameter on the magnetization values was observed and discussed in detail.


2011 ◽  
Vol 189-193 ◽  
pp. 1275-1279
Author(s):  
Ying Wang ◽  
Gao Yang Zhao ◽  
Li Yuan

The crystalline phase and morphology of the products formed during the synthesis of yttrium oxide via the hydrothermal treatment yttrium nitrate were characterized by X-ray diffraction, transmission electron microscopy and scanning electron microscopy. Products with high OH/NO3ratios are formed with the increasing of hydrothermal treatment. The crystalline phases are evolved from Y2(OH)5.14(NO3)0.86•H2O toY4O(OH)9(NO3) and finally Y(OH)3. The hydrothermal reaction conditions play an important role in the synthesis of the microstructures. Results show the particle size and final morphology of samples could be controlled by reaction temperature, reaction time, and OH-concentration. Sheets, hexagonal and needle-like Y2O3powders are obtained with the hydrothermal treatment of yittrium nitrate at 180 oC to 200oC for 2-8 hours at pH 9-13.


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