Structural Characterization of Nano-Crystalline BaTiO3 Powder Prepared Using Hydrothermal Method

2011 ◽  
Vol 324 ◽  
pp. 205-208 ◽  
Author(s):  
Ziyad S. A. Al Sarraj ◽  
Mukhlis M. Ismail ◽  
Sabah M. Ali ◽  
Wan Q. Cao

BaTiO3powders were prepared hydrothermally using TiCl4, Ba(OH)2.8H2O and NH4OH as starting materials at 150°C for 2h. The structure of the prepared nanocystalline BT powders were a metastable cubic perovskite according to XRD and HRTEM analysis, while FT Raman spectra showed that BT powders have a tetragonal structure. Hydroxyl and carbonate groups were observed in all prepared powders that showed in FTIR spectroscopy as vibrational bands. The tetragonal phase of BT powder was identified clearly by slow scan XRD at 2θ between 44.6 to 46°. The crystallite size of BT powders have increased with the increase of annealing temperature from 19 nm at room temperature to 70 nm at 1000°C.

1994 ◽  
Vol 47 (2) ◽  
pp. 391 ◽  
Author(s):  
CJ Kepert ◽  
BW Skeleton ◽  
AH White

The room-temperature single-crystal X-ray structural characterization of the title compound (tpyH2)2[Tb(OH2)8]Cl7.~2⅓H2O is recorded. Crystals are triclinic, Pī , a 17.063(5), b 16.243(3), c 7.878(3) Ǻ, α 84.78(2), β 84.39(3), γ 87.81(2)°, Z = 2 formula units; 3167 'observed' diffractometer reflections were refined by full-matrix least-squares procedures to a residual of 0.057. Notable features of interest of the compound are the 'chelation' of chloride ions by the terpyridinium cations , and the existence of a free [Tb(OH2)8]2+ cation in the presence of an abundance of chloride ions.


2006 ◽  
Vol 118 ◽  
pp. 53-58
Author(s):  
Elisabeth Meijer ◽  
Nicholas Armstrong ◽  
Wing Yiu Yeung

This study is to investigate the crystallite development in nanostructured aluminium using x-ray line broadening analysis. Nanostructured aluminium was produced by equal channel angular extrusion at room temperature to a total deformation strain of ~17. Samples of the extruded metal were then heat treated at temperatures up to 300oC. High order diffraction peaks were obtained using Mo radiation and the integral breadth was determined. It was found that as the annealing temperature increased, the integral breadth of the peak reflections decreased. By establishing the modified Williamson-Hall plots (integral breadth vs contract factor) after instrumental correction, it was determined that the crystallite size of the metal was maintained ~80 nm at 100oC. As the annealing temperature increased to 200oC, the crystallite size increased to ~118 nm. With increasing annealing temperature, the hardness of the metal decreased from ~60 HV to ~45 HV.


2017 ◽  
Vol 31 (02) ◽  
pp. 1750006 ◽  
Author(s):  
Mohammad Hossein Ghorbani ◽  
Abdol Mahmood Davarpanah

Manganese oxides are of more interest to researchers because of their ability as catalysts and lithium batteries. In this research, MnO2nanowires with diameter about 45 nm were synthesized by sol–gel method at room temperature (RT). Effect of increasing the annealing temperature from 400[Formula: see text]C to 600[Formula: see text]C on crystalline structure of nanostructure were studied and average crystallite size was estimated about 22 nm. X-ray Diffraction (XRD) method, Energy-Dispersive X-ray Diffraction (EDXD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) were used to characterize the nanowires of MnO2.


2017 ◽  
Vol 888 ◽  
pp. 57-61 ◽  
Author(s):  
Johar Banjuraizah ◽  
Tinesha Selvaraj ◽  
Zainal Arifin Ahmad

8 mol% of Yttrium oxide doped Zirconia (8YSZ) is one of the most explored compositions which give high ionic conductivities and good power output at 1000 °C. Generally, dopant was added to improve the sinterability of 8YSZ ceramics. In this present study, granulated 8YSZ powders with multimodal size was mixed with ZnO (0,1,2,3 wt%) using mortar and pestle. The mixed powder was compacted and sintered at 1550°C for 2 hours. 2 distinct endothermic peaks were observed in DTA plot of all samples. However, samples contain high amount of ZnO had a broader endothermic peak which resulted from the melting of ZnO. Rietveld refinement results indicate that the tetragonal phase appeared as the dominant phase for all doped and undoped samples, while cubic and monoclinic phase as the secondary phase. The monoclinic phase decreased as the amount of ZnO increased.


1994 ◽  
Vol 47 (1) ◽  
pp. 181 ◽  
Author(s):  
JM Harrowfield ◽  
AM Sargeson ◽  
BW Skelton ◽  
AH White

The room temperature X-ray single-crystal structural characterization of a protonated copper(II) complex of a ligand artefact, L′, of L = N-Me6sar (described in an accompanying paper) is recorded, the new ligand L′ being generated formally by elimination of a CH2CH2 bridge between a pair of nitrogen donor atoms of L. The complex, [ ClCu (H2L′) (ClO4)3.2H2O, is orthorhombic, Pccn , a 22.528(7), b 10.544(3), c 13.748(6) Ǻ, Z = 4 formula units, R being 0.053 for 1133 independent 'observed' [I > 3σ(I)] reflections. The cation, containing five-coordinate square-pyramidal ClCuN4 copper, is disposed with the Cu- Cl bond [2.458(3)Ǻ] lying on a crystallographic 2 axis; Cu-N distances are 2.094(8) and 2.093(8)Ǻ.


Polyhedron ◽  
2011 ◽  
Vol 30 (8) ◽  
pp. 1425-1429 ◽  
Author(s):  
R. Nagarajan ◽  
Neetu Tyagi ◽  
Samuel Lofland ◽  
K.V. Ramanujachary

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2804-2810 ◽  
Author(s):  
LEI MIAO ◽  
SAKAE TANEMURA ◽  
YASUHIKO HAYASHI ◽  
MASAKI TANEMURA ◽  
RONGPING WANG ◽  
...  

ZnO nanobamboos and nanowires with diameters of 10–30 nm and lengths of 2–4 μm have been prepared by laser ablation in vacuum with precisely controlled pressure, growth and post-annealing temperature. XRD results show the annealed sample is hexagonal ZnO . Low-magnified TEM observation reveals the annealed sample includes ZnO nanobamboos and nanowires. High resolution TEM image and electron diffraction pattern confirm that the structure of ZnO nanobamboo is regular stacking of Zn and O layers with high crystal quality. The growth direction is determined as along [001] direction (c axis). TEM observations confirm that the formation of bamboo-shape ZnO is due to the stacking fault and cleavage. The bundle of those stacking faults seems to be the origin of the black contrast at the nodes. The uniformity of chemical composition for the nanobamboos is identified by EDS profiles. A strong-narrow UV band centred at 390 nm and a weak-broad green band centred at 515 nm are observed at room temperature in the PL spectrum recorded from the annealed ZnO nanobamboos and nanowires.


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