Synthesis and Triple Conductive Properties of Ba and Fe Co-Doped Sr2TiO4 Based Layered Perovskite: (BaxSr2-x) (Ti0.9Fe0.1)O4-δ (X= 0.05, 0.10)

2021 ◽  
Vol 888 ◽  
pp. 37-42
Author(s):  
Yutaro Yagi ◽  
Isao Kagomiya ◽  
Ken-ichi Kakimoto
Keyword(s):  
Layered Perovskite ◽  
X Ray Diffraction ◽  
Ion Conductivities ◽  
Conductive Properties ◽  
Fe Ions ◽  
Ba Substitution ◽  
Oxide Ion ◽  
Layered Perovskites ◽  
Proton Defects ◽  
Proton Defect

This study investigated the effects of Ba substitution on protonic conductive properties in the Fe doped Sr2TiO4 layered perovskite. We synthesized sintered samples of (BaxSr2-x)(Ti0.90Fe0.10)O4-δ (x= 0.05, 0.10) (BSTF05, BSTF10). The result of X-ray diffraction suggests that solid solute limitation of Ba is between x= 0.05 and 0.10. BSTF05 at 600 °C shows proton and oxide-ion conductivities as well as elecronic conductivity. It means that BSTF05 is a triple conductor at 600 °C under oxidation atmosphere. The proton conductivities in BSTF05 are lower than that in Ba un-doped Sr2(Ti0.9Fe0.1)O4-δ evaluated in our previous work, suggesting that the effect of the Ba substitution on proton defect generation is small. The redox reaction of Fe ions is more important for creation of proton defects in the layered perovskites.

High oxide-ion conductivity in Si-deficient La9.565(Si5.826□0.174)O26 apatite without interstitial oxygens due to the overbonded channel oxygens

2018 ◽  
Vol 6 (23) ◽  
pp. 10835-10846 ◽  
Author(s):  
Kotaro Fujii ◽  
Masatomo Yashima ◽  
Keisuke Hibino ◽  
Masahiro Shiraiwa ◽  
Koichiro Fukuda ◽  
...  
Keyword(s):  
Single Crystal ◽  
Ion Conductivity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxide Ion Conductivity ◽  
Ion Conductivities ◽  
Lanthanum Silicates ◽  
Oxide Ion ◽  
Apatite Type

Overbonding of the channel oxygens in the apatite-type lanthanum silicates was found to be a key for the high oxide-ion conductivities by the present single-crystal neutron and X-ray diffraction studies.

scholarly journals Strategies for the Optimisation of the Oxide Ion Conductivities of Apatite-Type Germanates

Fuel Cells ◽  
2010 ◽  
Vol 11 (1) ◽  
pp. 10-16 ◽  
Author(s):  
A. Orera ◽  
T. Baikie ◽  
P. Panchmatia ◽  
T. J. White ◽  
J. Hanna ◽  
...  
Keyword(s):  
Ion Conductivities ◽  
Oxide Ion ◽  
Apatite Type

PHASE TRANSITION IN LAYERED PEROVSKITE LIKE MANGANATE Ca3Mn2O7 UNDER HIGH PRESSURE

2001 ◽  
Vol 15 (18) ◽  
pp. 2491-2497 ◽  
Author(s):  
J. L. ZHU ◽  
L. C. CHEN ◽  
R. C. YU ◽  
F. Y. LI ◽  
J. LIU ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Diamond Anvil Cell ◽  
The Other ◽  
Layered Perovskite ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Diamond Anvil

In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca 3 Mn 2 O 7 under pressures up to 35 GPa have been performed by using diamond anvil cell with synchrotron radiation. The results show that the structure of layered perovskite-like manganate Ca 3 Mn 2 O 7 is unstable under pressure due to the easy compression of NaCl-type blocks. The structure of Ca 3 Mn 2 O 7 underwent two phase transitions under pressures in the range of 0~35 GPa. One was at about 1.3 GPa with the crystal structure changing from tetragonal to orthorhombic. The other was at about 9.5 GPa with the crystal structure changing from orthorhombic back to another tetragonal.

scholarly journals Ion Transport Properties and Ionicity of 1,3-Dimethyl-1,2,3-Triazolium Salts with Fluorinated Anions

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1723 ◽  
Author(s):  
Martin Pulst ◽  
Yury Golitsyn ◽  
Detlef Reichert ◽  
Jörg Kressler
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Diffusion Coefficients ◽  
Important Class ◽  
Spectroscopy Data ◽  
Ion Conductivities ◽  
Electrochemical Devices ◽  
Pfg Nmr ◽  
Conductive Properties ◽  
Triazolium Salts

1,2,3-Triazolium salts are an important class of materials with a plethora of sophisticated applications. A series of three novel 1,3-dimethyl-1,2,3-triazolium salts with fluorine, containing anions of various size, is synthesized by methylation of 1,2,3-triazole. Their ion conductivity is measured by impedance spectroscopy, and the corresponding ionicities are determined by diffusion coefficients obtained from 1H and 19F pulsed field gradient nuclear magnetic resonance (PFG NMR) spectroscopy data, revealing that the anion strongly influences their ion conductive properties. Since the molar ion conductivities and ionicities of the 1,3-dimethyl-1,2,3-triazolium salts are enhanced in comparison to other 1,2,3-triazolium salts with longer alkyl substituents, they are promising candidates for applications as electrolytes in electrochemical devices.

scholarly journals OPTICAL PROPERTIES ON Li2O-K2O-WO3-B2O3 GLASS SYSTEM

2013 ◽  
Vol 22 ◽  
pp. 278-283
Author(s):  
A. EDUKONDALU ◽  
M. A. SAMEE ◽  
SHAIKH KAREEM AHMMAD ◽  
SAIR MD. TAQIULLAH ◽  
SYED RAHMAN ◽  
...  
Keyword(s):  
Glass Structure ◽  
Glass System ◽  
Alkali Concentration ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Mixed Alkali ◽  
Absorption Studies ◽  
Mixed Alkali Effect ◽  
Oxide Ion ◽  
B2o3 Glass

Mixed alkali tungsten borate glasses xLi2O–(30–x) K2O–10WO3–60B2O3 (0 < x < 30) were prepared from the melts. These glasses were characterized using X-ray diffraction, differential scanning calorimetry and density measurements. Optical absorption studies were carried out as a function of alkali content to look for mixed alkali effect (MAE) on the spectral properties of these glasses. From the study of ultraviolet absorption edge, the optical band gap energies and Urbach energies were evaluated. The average electronic polarizability of the oxide ion, optical basicity and the interaction parameters were also evaluated for all the glasses. Many of these parameters vary non-linearly exhibiting a minima or maxima with increasing alkali concentration, indicating the mixed alkali effect. An attempt is made to interpret MAE in this glass system in terms of its glass structure.

scholarly journals The Influence of the Ceramic Nanoparticles on the Thermoplastic Polymers Matrix: Their Structural, Optical, and Conductive Properties

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2773
Author(s):  
Ion Smaranda ◽  
Andreea Nila ◽  
Paul Ganea ◽  
Monica Daescu ◽  
Irina Zgura ◽  
...  
Keyword(s):  
Weight Ratio ◽  
Relaxation Processes ◽  
X Ray Diffraction ◽  
Thermoplastic Polymers ◽  
Dipolar Relaxation ◽  
Ceramic Nanoparticles ◽  
Preferential Adsorption ◽  
Conductive Properties ◽  
Ir Bands ◽  
Pl Quenching

This paper prepared composites under the free membranes form that are based on thermoplastic polymers of the type of polyurethane (TPU) and polyolefin (TPO), which are blended in the weight ratio of 2:1, and ceramic nanoparticles (CNs) such as BaSrTiO3 and SrTiO3. The structural, optical, and conductive properties of these new composite materials are reported. The X-ray diffraction studies highlight a cubic crystalline structure of these CNs. The main variations in the vibrational properties of the TPU:TPO blend induced by CNs consist of the following: (i) the increase in the intensity of the Raman line of 1616 cm−1; (ii) the down-shift of the IR band from 800 to 791 cm−1; (iii) the change of the ratio between the absorbance of IR bands localized in the spectral range 950–1200 cm−1; and (iv) the decrease in the absorbance of the IR band from 1221 cm−1. All these variations were correlated with a preferential adsorption of thermoplastic polymers on the CNs surface. A photoluminescence (PL) quenching process of thermoplastic polymers is demonstrated to occur in the presence of CNs. The anisotropic PL measurements have highlighted a change in the angle of the binding of the TPU:TPO blend, which varies from 23.7° to ≈49.3° and ≈53.4°, when the concentration of BaSrTiO3 and SrTiO3 CNs, respectively, is changed from 0 to 25 wt. %. Using dielectric spectroscopy, two mechanisms are invoked to take place in the case of the composites based on TPU:TPO blends and CNs, i.e., one regarding the type of the electrical conduction and another specifying the dielectric–dipolar relaxation processes.

Designing Mixed Oxides Magnetic Nanoparticles for Sensing Applications

2008 ◽  
Vol 1118 ◽  
Author(s):  
Monica Sorescu ◽  
L. Diamandescu ◽  
A. Tomescu ◽  
S. Krupa
Keyword(s):  
Mixed Oxides ◽  
Material System ◽  
X Ray Diffraction ◽  
Gas Concentration ◽  
Sensing Applications ◽  
Ideal System ◽  
Comparative Results ◽  
Xrd Patterns ◽  
Fe Ions ◽  
The Ideal

ABSTRACTZirconium-doped hematite particles of the type xZrO2-(1-x)α-Fe2O3 (x=0.1, 0.5) were synthesized using mechanochemical activation and characterized by X-ray diffraction (XRD) and Mössbauer spectroscopy. XRD patterns yielded the dependence of lattice parameters and particle size as a function of ball milling time for each value of the molar concentration x. The Mössbauer spectra were fitted with one or alternatively, four sextets, corresponding to Zr ions substituting Fe ions in the hematite structure and further required the addition of a quadrupole-split doublet, representing Fe substituting Zr in the ZrO2 lattice. We further correlated the structural properties of the zirconium-doped hematite system with the sensing properties. These were measured as function of temperature, gas concentration (carbon monoxide and methane) and variable humidity of air. The material system was found to be sensitive over the entire range of CO concentrations and the linearity of the sensor signal was not affected by the relative humidity of air, which makes it the ideal system for sensing devices. Comparative results obtained for tin-doped hematite nanoparticles are also presented.

scholarly journals The influence of stereochemically active lone-pair electrons on crystal symmetry and twist angles in lead apatite-2Htype structures

2014 ◽  
Vol 78 (2) ◽  
pp. 325-345 ◽  
Author(s):  
T. Baikie ◽  
M. Schreyer ◽  
F. Wei ◽  
J. S. Herrin ◽  
C. Ferraris ◽  
...  
Keyword(s):  
Single Crystal ◽  
Twist Angle ◽  
Lone Pair ◽  
Structural Data ◽  
Structural Adaptation ◽  
X Ray Diffraction ◽  
Temperature Changes ◽  
Waste Stabilization ◽  
Lone Pair Electrons ◽  
Oxide Ion

AbstractLead-containing (Pb-B-X)-2Hapatites encompass a number of [AF]4[AT]6[(BO4)6]X2compounds used for waste stabilization, environmental catalysis and ion conduction, but the influence of the stereochemically active lone-pair electrons of Pb2+on crystal chemistry and functionality is poorly understood. This article presents a compilation of existing structural data for Pb apatites that demonstrate paired electrons of Pb2+at both theAFandATresults in substantial adjustments to the PbFO6metaprism twist angle, φ. New structure refinements are presented for several natural varieties as a function of temperature by single-crystal X-ray diffraction (XRD) of vanadinite-2H(ideally Pb10(VO4)6Cl2), pyromorphite-2H(Pb10(PO4)6Cl2), mimetite-2H/M(Pb10(As5+O4)6Cl2) and finnemanite-2H(Pb10(As3+O3)6Cl2). A supercell for mimetite is confirmed using synchrotron single-crystal XRD. It is suggested the superstructure is necessary to accommodate displacement of the stereochemically active 6s2lone-pair electrons on the Pb2+that occupy a volume similar to an O2−anion. We propose that depending on the temperature and concentration of minor substitutional ions, the mimetite superstructure is a structural adaptation common to all Pb-containing apatites and by extension apatite electrolytes, where oxide ion interstitials are found at similar positions to the lonepair electrons. It is also shown that plumbous apatite framework flexes substantially through adjustments of the PbFO6metaprism twist-angles (φ) as the temperature changes. Finally, crystalchemical [100] zoning observed at submicron scales will probably impact on the treatment of diffraction data and may account for certain inconsistencies in reported structures.

scholarly journals Ferroelectric fatigue in layered perovskites from self-energy corrected density functional theory

RSC Advances ◽  
2017 ◽  
Vol 7 (35) ◽  
pp. 21856-21868 ◽  
Author(s):  
Kan-Hao Xue ◽  
Leonardo R. C. Fonseca ◽  
Xiang-Shui Miao
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Bismuth Titanate ◽  
Band Alignment ◽  
Layered Perovskite ◽  
Functional Theory ◽  
Self Energy ◽  
Layered Perovskites

We employed GGA-1/2 to investigate the band alignment between platinum and various layered perovskite Aurivillius ferroelectrics. A model is proposed for ferroelectric fatigue in bismuth titanate based on our calculation.

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