scholarly journals Association of oxygen vacancies with impurity metal ions in lead titanate

2007 ◽  
Vol 76 (17) ◽  
Author(s):  
Paul Erhart ◽  
Rüdiger-Albert Eichel ◽  
Petra Träskelin ◽  
Karsten Albe
Keyword(s):  
Metal Ions ◽  
Lead Titanate ◽  
Oxygen Vacancies ◽  
Impurity Metal

Incorporation of Impurity Metal Ions in Electrolytic Manganese Dioxide

1994 ◽  
Vol 141 (8) ◽  
pp. 2035-2040 ◽  
Author(s):  
Hiroki Tamura ◽  
Kenji Ishizeki ◽  
Masaichi Nagayama ◽  
Ryusaburo Furuichi
Keyword(s):  
Metal Ions ◽  
Manganese Dioxide ◽  
Electrolytic Manganese Dioxide ◽  
Electrolytic Manganese ◽  
Impurity Metal

Phase Transitions, Dielectric and Piezoelectric Properties of BiScO3-PbTiO3 Ceramic Solid Solutions

2012 ◽  
Vol 512-515 ◽  
pp. 1363-1366 ◽  
Author(s):  
Ekaterina D. Politova ◽  
Galina M. Kaleva ◽  
Alexander V. Mosunov ◽  
Andrei G. Segalla ◽  
Jiang Tao Zeng
Keyword(s):  
Phase Transitions ◽  
Dielectric Loss ◽  
Solid Solutions ◽  
Lead Titanate ◽  
Oxygen Vacancies ◽  
Piezoelectric Properties ◽  
Total Conductivity ◽  
Temperature Dependences ◽  
System 1 ◽  
Dielectric And Piezoelectric Properties

Dielectric and piezoelectric properties of ceramic solid solutions based on the compositions close to the MPB in the system (1-x)BiScO3 – xPbTiO3 (x- 0.63, 0.635, 0.64) have been studied. The 1st order phase transitions were observed at temperatures near 700 K. Increase in the lead titanate content stimulates slight increase in the TC value. Cr2O3 additives in amounts up to 0.2 w. % favor to the decrease of total conductivity and dielectric loss at high temperatures. Increase in the d33 and kt piezocoefficients was observed in modifed ceramic. Besides peaks in temperature dependences of dielectric permittivity and dielectric loss marked ferroelectric to paraelectric phase transitions, effects of dielectric relaxation, determined by oxygen vacancies were revealed.

Oxygen vacancies related electrical response in modified lead titanate ceramics

2009 ◽  
Vol 149 (45-46) ◽  
pp. 2082-2084 ◽  
Author(s):  
A. Peláiz-Barranco ◽  
Y. González-Abreu
Keyword(s):  
Lead Titanate ◽  
Oxygen Vacancies ◽  
Electrical Response ◽  
Titanate Ceramics

Unveiling the benefits of potassium doping on the structural integrity of Li–Mn-rich layered oxides during prolonged cycling by dual-mode EPR spectroscopy

2019 ◽  
Vol 21 (43) ◽  
pp. 24017-24025 ◽  
Author(s):  
Jianyin Wang ◽  
Mengchu Yang ◽  
Chong Zhao ◽  
Bei Hu ◽  
Xiaobing Lou ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Epr Spectroscopy ◽  
Oxygen Vacancies ◽  
Structural Integrity ◽  
Transition Metal Ions ◽  
Layered Oxides ◽  
Dual Mode

The migration of transition-metal ions and oxygen vacancies in the Li1.2Mn0.6Ni0.2O2 cathode is mitigated after K+ bulk doping.

scholarly journals Hybrid-RRAM toward Next Generation of Nonvolatile Memory: Coupling of Oxygen Vacancies and Metal Ions

2018 ◽  
Vol 5 (2) ◽  
pp. 1800658 ◽  
Author(s):  
Gilbert Sassine ◽  
Cécile Nail ◽  
Philippe Blaise ◽  
Benoit Sklenard ◽  
Mathieu Bernard ◽  
...  
Keyword(s):  
Metal Ions ◽  
Nonvolatile Memory ◽  
Oxygen Vacancies ◽  
Next Generation

HREM Study of electron-induced surface radiation damage in ReO3

1991 ◽  
Vol 49 ◽  
pp. 636-637
Author(s):  
R. Ai ◽  
H.-J. Fan ◽  
L. D. Marks
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Metal Oxides ◽  
Electron Irradiation ◽  
Transition Metal Oxides ◽  
Carbon Film ◽  
Transition Metal Ions ◽  
Surface Radiation ◽  
Valence Transition ◽  
Electron Microscopes

It has been known for a long time that electron irradiation induces damage in maximal valence transition metal oxides such as TiO2, V2O5, and WO3, of which transition metal ions have an empty d-shell. This type of damage is excited by electronic transition and can be explained by the Knoteck-Feibelman mechanism (K-F mechanism). Although the K-F mechanism predicts that no damage should occur in transition metal oxides of which the transition metal ions have a partially filled d-shell, namely submaximal valence transition metal oxides, our recent study on ReO3 shows that submaximal valence transition metal oxides undergo damage during electron irradiation.ReO3 has a nearly cubic structure and contains a single unit in its cell: a = 3.73 Å, and α = 89°34'. TEM specimens were prepared by depositing dry powders onto a holey carbon film supported on a copper grid. Specimens were examined in Hitachi H-9000 and UHV H-9000 electron microscopes both operated at 300 keV accelerating voltage. The electron beam flux was maintained at about 10 A/cm2 during the observation.

ELNES of Iron Compounds

1990 ◽  
Vol 48 (2) ◽  
pp. 28-29
Author(s):  
Hiroki Kurata ◽  
Kazuhiro Nagai ◽  
Seiji Isoda ◽  
Takashi Kobayashi
Keyword(s):  
Energy Loss ◽  
Metal Ions ◽  
Energy Resolution ◽  
Transition Metal Oxides ◽  
Local Symmetry ◽  
Iron Compounds ◽  
Fine Structures ◽  
Electron Energy Loss ◽  
Fe Ions ◽  
Electron Energy Loss Spectra

Electron energy loss spectra of transition metal oxides, which show various fine structures in inner shell edges, have been extensively studied. These structures and their positions are related to the oxidation state of metal ions. In this sence an influence of anions coordinated with the metal ions is very interesting. In the present work, we have investigated the energy loss near-edge structures (ELNES) of some iron compounds, i.e. oxides, chlorides, fluorides and potassium cyanides. In these compounds, Fe ions (Fe2+ or Fe3+) are octahedrally surrounded by six ligand anions and this means that the local symmetry around each iron is almost isotropic.EELS spectra were obtained using a JEM-2000FX with a Gatan Model-666 PEELS. The energy resolution was about leV which was mainly due to the energy spread of LaB6 -filament. The threshole energies of each edges were measured using a voltage scan module which was calibrated by setting the Ni L3 peak in NiO to an energy value of 853 eV.

Conditions for atomic imaging of mullite

1989 ◽  
Vol 47 ◽  
pp. 418-419
Author(s):  
T. A. Epicier ◽  
G. Thomas
Keyword(s):  
Oxygen Vacancies ◽  
High Resolution Electron Microscopy ◽  
Ceramic Materials ◽  
Work Conditions ◽  
Real Space ◽  
Potential Candidate ◽  
Silicate Mineral ◽  
Resolution Electron ◽  
The Subject ◽  
Aluminium Silicate

Mullite is an aluminium-silicate mineral of current interest since it is a potential candidate for high temperature applications in the ceramic materials field.In the present work, conditions under which the structure of mullite can be optimally imaged by means of High Resolution Electron Microscopy (HREM) have been investigated. Special reference is made to the Atomic Resolution Microscope at Berkeley which allows real space information up to ≈ 0.17 nm to be directly transferred; numerous multislice calculations (conducted with the CEMPAS programs) as well as extensive experimental through-focus series taken from a commercial “3:2” mullite at 800 kV clearly show that a resolution of at least 0.19 nm is required if one wants to get a straightforward confirmation of atomic models of mullite, which is known to undergo non-stoichiometry associated with the presence of oxygen vacancies.Indeed the composition of mullite ranges from approximatively 3Al2O3-2SiO2 (referred here as 3:2-mullite) to 2Al2O3-1SiO2, and its structure is still the subject of refinements (see, for example, refs. 4, 5, 6).

Sign in / Sign up

Export Citation Format

Share Document