X-ray powder diffraction structural characterization of Ba1-xEuxTiO3 ternary oxides

Lu, Da-Yong; Sugano, Mikio; Su, Wenhui; Koda, T.

doi:10.1002/crat.200410412

Cited by 19 publications

(6 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These secondary phases are typically observed in Eu 3+ -doped BaTiO 3 ceramics synthesized via high-temperature solid-state reaction. [13][14][15][16] Transmission electron microscopy (TEM) images of a representative Eu:BaTiO 3 nanocrystal sample are shown in Fig. 1b The local crystal structure of the Eu:BaTiO 3 nanocrystals was probed using PDF analysis of X-ray total scattering data.…”

Section: Resultsmentioning

confidence: 99%

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

et al. 2014

View full text Add to dashboard Cite

A structural investigation of sub-15 nm xEu:BaTiO3 nanocrystals (x = 0-5 mol%) was conducted to determine the distribution of the Eu(3+) ion in the BaTiO3 lattice. Pair distribution function analysis of X-ray total scattering data (PDF), steady-state photoluminescence, and X-ray absorption spectroscopy (XANES/EXAFS) were employed to interrogate the crystal structure of the nanocrystals and the local atomic environment of the Eu(3+) ion. The solubility limit of the Eu(3+) ion in the nanocrystalline BaTiO3 host synthesized via the vapor diffusion sol-gel method was estimated to be ∼4 mol%. A contraction of the perovskite unit cell volume was observed upon incorporation of 1 mol% of europium, while an expansion was observed for nominal concentrations between 1 and 3 mol%. The average Eu-O distance and europium coordination number decreased from 2.46 Å and 9.9 to 2.42 Å and 8.6 for europium concentrations of 1 and 5 mol%, respectively. Structural trends were found to be consistent with the substitution of Eu(3+) for Ba(2+)via creation of a Ti(4+) vacancy at low europium concentrations (<1 mol%), and with the substitution of Eu(3+) for both Ba(2+) and Ti(4+) at high europium concentrations (1-3 mol%). The significance of accounting for local structural distortions to rationalize the distribution of lanthanide ions in the perovskite host is highlighted.

show abstract

Section: Resultsmentioning

confidence: 99%

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Lattice parameters and unit cell volume were calculated by MS Modeling (Accelrys) using Cu K 1 radiation ( ¼ 1:540562 A), as described elsewhere. 15) Raman spectra were measured at room temperature using a LabRAM XploRA Raman spectrometer (Horiba Jobin Yvon) with the 532 nm excitation.…”

Section: Methodsmentioning

confidence: 99%

Raman Evidence for Ba-Site Ce³⁺ in BaTiO₃

Han

Sun

et al. 2013

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

To obtain evidence of the existence of Ce3+ at Ba sites in BaTiO3, the nominal (Ba1-x Ce x )Ti1-x/4O3 (BCT) and Ba(Ti1-x Ce x )O3 (BTC) ceramics prepared under different conditions were investigated by Raman spectroscopy. A band at ∼840 cm-1 that appears in all BCT samples is evidence of the existence of Ce3+ at Ba sites in the BaTiO3 lattice. For BTC, Raman scattering experiments give convincing evidence that a small number of Ce ions inevitably enter Ba sites as Ce3+, which can be expressed by (Ba,Ceδ)(Ti,Ce x-δ)O3, where δ≈2 ‰.

show abstract

“…In compounds, Eu may exist as metastable Eu 2þ ions with a half-filled 4f shell (electronic configuration: 4f 7 ), 4) Eu 3þ ions (4f 6 ) 5) or mixed Eu 2þ (4f 7 )/Eu 3þ (4f 6 ) ions. 6,7) For single-phase (Ba 1Àx Eu x )TiO 3 (solid solubility limit up to 40%) prepared by hot pressing, 8) it was found by X-ray photoelectron Spectroscopy (XPS) that mixed Eu 2þ /Eu 3þ coexist and the ratio of Eu 2þ /Eu 3þ is nearly equal to 1. 9) However, for EBT dielectric ceramics, there is still insufficient evidence for clearly understanding the valence state of Eu in BaTiO 3 and defect chemistry owing to the limitation of the lower Eu concentration in EBT to XPS technique and the emergence of the Eu 2 Ti 2 O 7 phase.…”

mentioning

confidence: 99%

Electron Spin Resonance Investigations and Compensation Mechanism of Europium-Doped Barium Titanate Ceramics

Sun

Takada

2006

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

The electron spin resonance (ESR) technique was employed to investigate the point defects and evidence of Eu2+ in Eu-doped barium titanate (EBT) ceramics sintered in air according to the formula (Ba1-x Eu x )Ti1-x/8O3. The charge equilibrium compensation mechanism was discussed on the basis of ESR with the aid of X-ray diffraction (XRD) and differential scanning calorimetric (DSC) techniques. Eu is incorporated into Ba sites of BaTiO3 as Eu3+ up to x=0.02 and as mixed Eu2+/Eu3+ at x=0.03, which is evidenced by Eu3+-induced Ti-vacancy defects with g=2.004 and a broad Eu2+ signal with g=1.98, and a single-phase tetragonal perovskite structure can be retained. When x≥0.04, it is concluded that high density and low porosity in highly insulating and fine-grained EBT ceramics originate from the coexistence of mixed Eu2+/Eu3+; in particular, the increase in the proportion of Eu2+ in the perovskite phase increases ceramic density, but is accompanied by emergence of the Eu2Ti2O7 phase.

show abstract

X-ray powder diffraction structural characterization of Ba1-xEuxTiO3 ternary oxides

Cited by 19 publications

References 16 publications

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

Raman Evidence for Ba-Site Ce³⁺ in BaTiO₃

Electron Spin Resonance Investigations and Compensation Mechanism of Europium-Doped Barium Titanate Ceramics

Contact Info

Product

Resources

About

X-ray powder diffraction structural characterization of Ba1-xEuxTiO3 ternary oxides

Cited by 19 publications

References 16 publications

Local structural investigation of Eu3+-doped BaTiO3nanocrystals

Local structural investigation of Eu3+-doped BaTiO3nanocrystals

Raman Evidence for Ba-Site Ce3+ in BaTiO3

Electron Spin Resonance Investigations and Compensation Mechanism of Europium-Doped Barium Titanate Ceramics

Contact Info

Product

Resources

About

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

Local structural investigation of Eu³⁺-doped BaTiO₃nanocrystals

Raman Evidence for Ba-Site Ce³⁺ in BaTiO₃