Contemporary Apparatus for Single Crystals Growth of Oxide Compounds and Metals by Optical Floating Zone (FZ)

A contemporary apparatus with radiation (light) heating for growth of single crystals of refractory oxides and metals is described. To reduce the dissociation or evaporation of the melt or crystal components, the growth process was carried out in oxygen or an alternative gas at pressures up to 100 bar. The annealing system applied directly in the growth process at 1650 °C under O2 pressure and at temperatures up to 2500 °C under protective gas flow, allows the obtaining of large and perfect single crystals. Many single crystals of oxide materials, including incongruently melting substances, such as Y3Fe5O12, Gd3Fe5O12, BaFe12O19, SrFe12O19, BaFe12-x AlxO19, and many others have been grown, and much more could be grown.

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Growth process of gas bubble in ruby single crystals by floating zone method

Journal of Crystal Growth ◽

10.1016/0022-0248(86)90129-6 ◽

1986 ◽

Vol 74 (2) ◽

pp. 385-390 ◽

Cited By ~ 15

Author(s):

M. Saito

Keyword(s):

Single Crystals ◽

Growth Process ◽

Gas Bubble ◽

Floating Zone ◽

Zone Method ◽

Floating Zone Method

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Effects of Variable Microaccelerations on Distribution of Impurity Inhomogeneities in the InSb: Te Single Crystals Grown by the Floating Zone Melting on the \Foton\" Satellite"

10.2514/6.iac-04-j.3.03 ◽

2004 ◽

Keyword(s):

Single Crystals ◽

Zone Melting ◽

Floating Zone

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Thermochemical Energy Storage Performance Analysis of (Fe,Co,Mn)Ox Mixed Metal Oxides

Catalysts ◽

10.3390/catal11030362 ◽

2021 ◽

Vol 11 (3) ◽

pp. 362

Author(s):

Yabibal Getahun Dessie ◽

Qi Hong ◽

Bachirou Guene Lougou ◽

Juqi Zhang ◽

Boshu Jiang ◽

...

Keyword(s):

Energy Storage ◽

Metal Oxide ◽

Metal Oxides ◽

Redox Reaction ◽

Gas Flow ◽

Oxygen Exchange ◽

Engineering Industry ◽

Oxide Material ◽

Oxide Materials ◽

Uptake Ratio

Metal oxide materials are known for their ability to store thermochemical energy through reversible redox reactions. Metal oxides provide a new category of materials with exceptional performance in terms of thermochemical energy storage, reaction stability and oxygen-exchange and uptake capabilities. However, these characteristics are predicated on the right combination of the metal oxide candidates. In this study, metal oxide materials consisting of pure oxides, like cobalt(II) oxide, manganese(II) oxide, and iron(II, III) oxide (Fe3O4), and mixed oxides, such as (100 wt.% CoO, 100 wt.% Fe3O4, 100 wt.% CoO, 25 wt.% MnO + 75 wt.% CoO, 75 wt.% MnO + 25 wt.% CoO) and 50 wt.% MnO + 50.wt.% CoO), which was subjected to a two-cycle redox reaction, was proposed. The various mixtures of metal oxide catalysts proposed were investigated through the thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), energy dispersive X-ray (EDS), and scanning electron microscopy (SEM) analyses. The effect of argon (Ar) and oxygen (O2) at different gas flow rates (20, 30, and 50 mL/min) and temperature at thermal charging step and thermal discharging step (30–1400 °C) during the redox reaction were investigated. It was revealed that on the overall, 50 wt.% MnO + 50 wt.% CoO oxide had the most stable thermal stability and oxygen exchange to uptake ratio (0.83 and 0.99 at first and second redox reaction cycles, respectively). In addition, 30 mL/min Ar–20 mL/min O2 gas flow rate further increased the proposed (Fe,Co,Mn)Ox mixed oxide catalyst’s cyclic stability and oxygen uptake ratio. SEM revealed that the proposed (Fe,Co,Mn)Ox material had a smooth surface and consisted of polygonal-shaped structures. Thus, the proposed metallic oxide material can effectively be utilized for high-density thermochemical energy storage purposes. This study is of relevance to the power engineering industry and academia.

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The growth of barium tetratitanate (BaTi4O9) single crystals by the floating zone method

Journal of Crystal Growth ◽

10.1016/0022-0248(86)90376-3 ◽

1986 ◽

Vol 76 (2) ◽

pp. 311-316 ◽

Cited By ~ 5

Author(s):

Isao Tanaka ◽

Hironao Kojima ◽

Fumiaki Sudo

Keyword(s):

Single Crystals ◽

Floating Zone ◽

Zone Method ◽

Floating Zone Method

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The growth of tapiolite (FeTa2O6) single crystals by the floating zone method

Journal of Crystal Growth ◽

10.1016/0022-0248(85)90343-4 ◽

1985 ◽

Vol 73 (1) ◽

pp. 175-178 ◽

Cited By ~ 5

Author(s):

Isao Tanaka ◽

Hiroshi Kanai ◽

Hironao Kojima

Keyword(s):

Single Crystals ◽

Floating Zone ◽

Zone Method ◽

Floating Zone Method

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Characterization of Natural and Synthesized FeTiO3 Crystals With RBS/PIXE/XRD

International Journal of PIXE ◽

10.1142/s0129083597000308 ◽

1997 ◽

Vol 07 (03n04) ◽

pp. 265-275

Author(s):

R. Q. Zhang ◽

S. Yamamoto ◽

Z. N. Dai ◽

K. Narumi ◽

A. Miyashita ◽

...

Keyword(s):

Single Crystals ◽

Ion Beam ◽

Pressure Control ◽

Floating Zone ◽

X Ray Diffraction ◽

X Ray ◽

Beam Analysis ◽

Ppm Level

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.

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