Mixed layered Aurivillius phases

Crystal Engineering of Bi2WO6 to Polar Aurivillius-Phase Oxyhalides

10.26434/chemrxiv.9741701.v1 ◽

2019 ◽

Author(s):

Kazuki Morita ◽

Ji-Sang Park ◽

Sunghyun Kim ◽

Kenji Yasuoka ◽

Aron Walsh

Keyword(s):

Photocatalytic Activity ◽

Crystal Engineering ◽

First Principles ◽

Parent Compound ◽

Aurivillius Phase ◽

Aurivillius Phases ◽

Charge Neutrality ◽

Bismuth Oxides ◽

Structure Surface ◽

Electric Dipoles

The Aurivillius phases of complex bismuth oxides have attracted considerable attention due to their lattice polarization (ferroelectricity) and photocatalytic activity. We report a first-principles exploration of Bi2WO6 and the replacement of W6+ by pentavalent (Nb5+, Ta5+) and tetravalent (Ti4+, Sn4+) ions, with charge neutrality maintained by the formation of a mixed-anion oxyhalide sublattice. We find that Bi2SnO4F2 is thermodynamically unstable, in contrast to Bi2TaO5F, Bi2NbO5F and Bi2TiO4F2. The electric dipoles introduced by chemical substitutions in the parent compound are found to suppress the spontaneous polarization from 61.55 μC/cm2 to below 15.50 μC/cm2. Analysis of the trends in electronic structure, surface structure, and ionization potentials are reported. This family of materials can be further extended with control of layer thicknesses and choice of compensating halide species.

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Crystal structure of Bi2W2O9, the n=2 member of the homologous series (Bi2O2)BVInO3n+1 of cation-deficient Aurivillius phases

Journal of Materials Chemistry ◽

10.1039/a900992b ◽

1999 ◽

Vol 9 (6) ◽

pp. 1319-1322 ◽

Cited By ~ 50

Author(s):

Jean-Claude Champarnaud-Mesjard ◽

Bernard Frit ◽

Akiteru Watanabe

Keyword(s):

Crystal Structure ◽

Homologous Series ◽

Aurivillius Phases

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Continuous Structural Evolution of (Bi2O2)2V2yO4y+2(1 ≤y≤ 4) Aurivillius Phases in the Bi2O3–VO2System

Journal of Solid State Chemistry ◽

10.1006/jssc.1996.0264 ◽

1996 ◽

Vol 125 (1) ◽

pp. 54-62 ◽

Cited By ~ 15

Author(s):

Svetlana Sorokina ◽

Renée Enjalbert ◽

Pierre Baules ◽

Alicia Castro ◽

Jean Galy

Keyword(s):

Structural Evolution ◽

Aurivillius Phases

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Hydrothermal synthesis of ABi2Ta2O9Aurivillius phase: A comparative study of A-site cation size on structure, dielectric, optical properties

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21500302 ◽

2021 ◽

Author(s):

Ilona Bella ◽

Tio Putra Wendari ◽

Novesar Jamarun ◽

Nandang Mufti ◽

Zulhadjri

Keyword(s):

Xrd Analysis ◽

Aurivillius Phase ◽

Hydrothermal Route ◽

Orthorhombic Crystal ◽

Ionic Radii ◽

Aurivillius Phases ◽

Orthorhombic Crystal Structure ◽

A Site ◽

Cation Size ◽

Ferroelectric Transition Temperature

In this study, the double-layered Aurivillius phases CaBi2Ta2O9 (CBT) and PbBi2Ta2O9 (PBT) were prepared through a hydrothermal route with NaOH as a mineralizer. XRD analysis confirmed that the CBT and PBT compounds were successfully formed and adopted an orthorhombic crystal structure with an [Formula: see text]21am symmetry. Le Bail refinements of XRD data indicated that the unit cell volume of CBT was smaller than PBT and is associated with the smaller ionic radius of Ca[Formula: see text] compared to Pb[Formula: see text]. The surface morphology of both samples, as determined using SEM, demonstrated plate-like grains with anisotropic grain growth. It was found that the different ionic radii of [Formula: see text]-site cations (Ca[Formula: see text] and Pb[Formula: see text] strongly affected the structural, optical and electrical properties of the Aurivillius phase. The occupation of smaller Ca[Formula: see text] cations induced a higher structural distortion, which resulted in higher bandgap ([Formula: see text] energy and ferroelectric transition temperature ([Formula: see text] of CBT, compared to those of PBT.

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Optical constants of MOCVD-grown Aurivillius phases in the Bi4Ti3O12–Na0.5Bi0.5TiO3 system measured by spectroscopic ellipsometry

Applied Physics A ◽

10.1007/s00339-011-6581-z ◽

2011 ◽

Vol 105 (1) ◽

pp. 81-88 ◽

Cited By ~ 1

Author(s):

S. Bin Anooz ◽

J. Schwarzkopf ◽

P. Petrik ◽

M. Schmidbauer ◽

A. Duk ◽

...

Keyword(s):

Spectroscopic Ellipsometry ◽

Optical Constants ◽

Aurivillius Phases

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Five Layers Aurivillius Phases Pb2-xBi4+xTi5-xMnxO18: Synthesis, Structure, Relaxor Ferroelectric and Magnetic Properties

ITB journal of Sciences ◽

10.5614/itbj.sci.2011.43.2.6 ◽

2011 ◽

Vol 43 (2) ◽

pp. 139-150 ◽

Cited By ~ 1

Author(s):

Zulhadjri Zulhadjri ◽

B. Prijamboedi ◽

A. A. Nugroho ◽

N. Mufti ◽

Ismunandar Ismunandar

Keyword(s):

Magnetic Properties ◽

Relaxor Ferroelectric ◽

Aurivillius Phases

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Relation between tolerance factor and Tc in Aurivillius compounds

Journal of Materials Research ◽

10.1557/jmr.2001.0433 ◽

2001 ◽

Vol 16 (11) ◽

pp. 3139-3149 ◽

Cited By ~ 174

Author(s):

Donají Y. Suárez ◽

Ian M. Reaney ◽

William E. Lee

Keyword(s):

Room Temperature ◽

Ferroelectric Phase ◽

Structural Phase ◽

Tolerance Factor ◽

Structural Phase Transitions ◽

Aurivillius Phases ◽

Ferroelectric Phase Transition Temperature ◽

Transmission Electron ◽

Octahedral Tilting ◽

Permittivity Measurements

The structures and microstructures of a range of Aurivillius phases were investigated by transmission electron microscopy. Systematic rows of superlattice reflections arising from tilting of octahedra around the c axis were identified, and their intensities at room temperature were shown to diminish as the tolerance factor (t) of the perovskite blocks increased. For compounds with t's approaching 1, no superlattice reflections were observed. the paraelectric-to-ferroelectric phase transition temperature (Tc) was monitored through permittivity measurements as a function of temperature, and Tc was also shown to decrease as t increased. Consequently, the onset of octahedral tilting and Tc appeared to be strongly related Aurivillius phases. Planar defects arising from the structural phase transitions and from stacking irregularities were also discussed.

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Phase Formation Kinetics in Sol-Gel Derived Strontium Bismith Tantalate

MRS Proceedings ◽

10.1557/proc-666-f7.4 ◽

2001 ◽

Vol 666 ◽

Cited By ~ 1

Author(s):

Yun-Mo Sung ◽

Woo-Chul Kwack

Keyword(s):

Activation Energy ◽

Thermal Analysis ◽

Phase Formation ◽

Sol Gel ◽

Avrami Exponent ◽

Fluorite Phase ◽

X Ray Diffraction ◽

Aurivillius Phases ◽

Formation Kinetics ◽

Isothermal Kinetic

ABSTRACTPhase formation characteristics of Sr0.7Bi2.4Ta2O9 (SBT) powder, synthesized via sol-gel and pyrolysis process, was investigated by using thermal analysis. Each of the two exotherms, appearing in differential thermal analysis (DTA) scan curves, was identified as crystallization of fluorite phase and transformation of fluorite to aurivillius phase, respectively by using x-ray diffraction (XRD). By applying non-isothermal kinetic analyses to the DTA results, activation energy values for the formation of fluorite and aurivillius phases were determined as 192 and 375 kJ/mol, respectively and Avrami exponent values for each reaction were determined as 0.91 and 0.96, respectively. These activation energy and Avrami exponent values were discussed in detail to understand phase formation mechanism in SBT system.

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