ChemInform Abstract: EFFECT OF ADDITIONS OF TRANSITION-METAL OXIDES ON THE CORROSION KINETICS OF A POTASSIUM OXIDE-SODIUM OXIDE-BARIUM OXIDE-SILICON DIOXIDE GLASS IN AQUEOUS POTASSIUM HYDROXIDE SOLUTIONS

AbstractIn the present paper the theoretical basis and experimental verification of a method, enabling the calculation of defect concentration and their mobility in transition metal oxides and sulphides have been described. The idea of proposed method consists in determination of both these parameters in indirect way, i.e. in studying the influence of aliovalent metallic additions on the oxidation kinetics of a given metal (doping effect). It has been shown that from the results of oxidation kinetics of binary alloys, the enthalpy and entropy of defect formation and their migration can be calculated. These data, in turn, can be used for the calculation of defect concentration and defect mobility in pure, undoped oxides. Such a possibility has been illustrated on the example of nonstoichiometric nickel oxide, Ni

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Synergetic Effect of Oxides on Hydrogen Reaction Kinetics of Magnesium Hydride

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1605 ◽

2007 ◽

Vol 561-565 ◽

pp. 1605-1608

Author(s):

Aep Patah ◽

Akito Takasaki ◽

Janusz S. Szmyd

Keyword(s):

Transition Metal ◽

Metal Oxides ◽

Reaction Kinetics ◽

Transition Metal Oxides ◽

Hydrogen Absorption ◽

Catalytic Effect ◽

Synergetic Effect ◽

Desorption Kinetics ◽

Absorption Kinetics ◽

Kinetics Of

The kinetics of hydrogen reaction (absorption and desorption) on the MgH2 have been reported to be improved significantly by addition of transition metal oxides as catalysts. Among the oxides reported previously, Cr2O3 seems to improve hydrogen absorption kinetics and Nb2O5 for desorption kinetics. The catalytic effect of addition of more than one oxide, however, has not been reported yet. We investigated the hydrogen reaction kinetics of ball milled MgH2 powders added with either Cr2O3 or ZnO together with Nb2O5. In absorption reaction, the hydrogen contents reached 6 wt% and 5.3 wt% in 5 min for the powders added with 1 mol% ZnO + 1 mol% Nb2O5 and with 1 mol% Cr2O3 + 1 mol% Nb2O5, respectively. Those powders desorbed hydrogen up to about 4.5 wt% in 20 min. The significant improvement was not expected if one of the oxides was added separately. The combination of two kinds of oxides might play an important role for improvement of reaction kinetics.

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Toward the rational design of non-precious transition metal oxides for oxygen electrocatalysis

Energy & Environmental Science ◽

10.1039/c4ee03869j ◽

2015 ◽

Vol 8 (5) ◽

pp. 1404-1427 ◽

Cited By ~ 959

Author(s):

Wesley T. Hong ◽

Marcel Risch ◽

Kelsey A. Stoerzinger ◽

Alexis Grimaud ◽

Jin Suntivich ◽

...

Keyword(s):

Fuel Cells ◽

Transition Metal ◽

Metal Oxides ◽

Transition Metal Oxides ◽

Rational Design ◽

Artificial Photosynthesis ◽

Solar Fuels ◽

Oxide Catalysts ◽

Perovskite Oxide ◽

Kinetics Of

The rational design of non-precious transition metal perovskite oxide catalysts holds exceptional promise for understanding and mastering the kinetics of oxygen electrocatalysis instrumental to artificial photosynthesis, solar fuels, fuel cells, electrolyzers, and metal–air batteries.

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Dehydriding kinetics of mechanically alloyed mixtures of magnesium with some 3d transition metal oxides

International Journal of Hydrogen Energy ◽

10.1016/0360-3199(91)90019-f ◽

1991 ◽

Vol 16 (4) ◽

pp. 265-270 ◽

Cited By ~ 8

Author(s):

M TERZIEVA ◽

M KHRUSSANOVA ◽

P PESHEV

Keyword(s):

Transition Metal ◽

Metal Oxides ◽

Transition Metal Oxides ◽

Mechanically Alloyed ◽

Kinetics Of

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High permittivity dielectrics

Semiconductor Physics ◽

10.1093/oso/9780198759867.003.0018 ◽

2020 ◽

pp. 618-631

Author(s):

Sandip Tiwari

Keyword(s):

Transition Metal ◽

Silicon Dioxide ◽

Metal Oxides ◽

Transition Metal Oxides ◽

Hafnium Oxide ◽

Field Effect ◽

Low Frequency ◽

Phonon Energy ◽

High Permittivity ◽

Ionic Polarization

This chapter discusses high permittivity dielectrics such as hafnium oxide and zirconium oxide and how the phonons of such materials, their band and polarization behavior and silicon interact. High permittivity materials are used as dielectrics with semiconductors. A prominent use for these materials is in suppressing tunneling while enhancing the field effect. High permittivity arises strongly from ionic polarization. So, the low frequency response for high permittivity materials is very different from that of silicon dioxide. Transition metal oxides’ high permittivity comes together with soft phonons. With phonons soft, that is of low phonon energy, the interactions and transport behavior of semiconductors can change significantly through a modified Fröhlich interaction, because of the presence of high permittivity materials nearby. These various issues are analyzed.

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