Results 11 to 20 of about 712 (189)

Origin of ferroelectric polarization in tetragonal tungsten-bronze-type oxides [PDF]

Physical Review B, 2016
The origin of ferroelectric polarization in tetragonal tungsten-bronze- (TTB-) type oxide strontium barium niobate (SBN) is investigated using first-principles density functional calculations. We study in particular the relationship between the polarization and the cation and vacancy ordering on alkali-earth metal lattice sites.
Gerhard Henning Olsen, Ulrich Aschauer, Nicola A. Spaldin, Sverre Magnus Selbach, Tor Grande   +4 more
openaire   +4 more sources

Effect of B-site Zr and Hf substitution on ferroelectric polar order for tetragonal tungsten bronze ceramic

Journal of Asian Ceramic Societies, 2022
Lead free ferroelectric ceramic Ba4Sm2Hf4Nb6O30(BSHN) with tungsten bronze structure was synthesized and characterized. The effect of B-site cation electron configuration (Hf and Zr) on origin of ferroelectricity and polarization reversal was also ...
Wenbin Feng, Sidi Long, Yi Wan, Dunpu Zhang   +3 more
doaj   +2 more sources

Análise cristalográfica da solução sólida com estrutura tipo Tungstênio Bronze de niobato de potássio e estrôncio dopado com ferro Crystallographic analysis of the solid solution of iron doped potassium strontium niobate with tetragonal tungsten bronze structure [PDF]

Química Nova, 2010
Solid solution of iron doped potassium strontium niobate with KSr2(FeNb4)O15-Δ stoichiometry was prepared by high efficiency ball milling method. Structural characterization was carried out by X-ray diffraction. Crystalline structure was analyzed by
Silvania Lanfredi, Marcos A. L. Nobre, Alan R. F. Lima   +2 more
doaj   +2 more sources

Ordering Principles in Niobium Tungsten Oxides of the Tetragonal Tungsten Bronze Type

Zeitschrift für anorganische und allgemeine Chemie
In the system Nb 2 O 5 /WO 3 , phases with structures related to the tetragonal tungsten bronze (TTB) type occur at three well‐defined compositions: Nb 2 WO
Frank Krumeich, Michael Wörle
openaire   +2 more sources

Mo–W-containing tetragonal tungsten bronzes through isomorphic substitution of molybdenum by tungsten

Catalysis Today, 2010
Mixed metal oxides based in Mo(W)–Nb–V–Te with tetragonal tungsten bronze (TTB) structure have been synthesized by a hydrothermal method from aqueous solutions of the corresponding Keggin-type heteropolyacids and further heat-treatment in N2 at 700 ◦ C. The materials have been characterized by several physico-chemical techniques, i.e. XRD, Raman, FTIR,
BOTELLA ASUNCION, PABLO, López Nieto, José Manuel, Concepción Heydorn, Patricia, Jorda Moret, Jose Luis, Domenech Carbo, Mª Teresa, Solsona Espriu, Benjamin Eduardo   +5 more
openaire   +3 more sources

Ferroelectric-Polarization-Driven Structural Engineering of Bi₃Nb₁₇O₄₇ Anodes for High-Performance Lithium-Ion Batteries. [PDF]

Adv Sci (Weinh)
A transformative ferroelectric‐polarization strategy is employed to overcome the intrinsic limitations of tungsten bronze (TTB)‐type anode materials in metal‐ion batteries, using Bi3Nb17O47 as a model system. By exploiting the non‐centrosymmetric crystal structure and field‐induced ionic displacements, controlled structural engineering with ...
Lou X, Li S, Lin C, Li Y, Sun M, Liu Z, Nie W, Tang X, Wang B, Cao W, Che R.   +10 more
europepmc   +2 more sources

Phonons and relaxations in unfilled tetragonal tungsten-bronzes

OAJ Materials and Devices, 2021
The lead-free unfilled tetragonal tungsten-bronzes SBN and CBN are investigated by Raman, infrared and high-frequency dielectric spectroscopies. The substitution in the different channels affects phonons as well as relaxations. Relaxations in SBN show similar qualitative behaviour on increasing Sr content and relaxor behaviour, but for the extreme ...
Buixaderas, Elena, Dec, Jan
openaire   +4 more sources

Novel polar dielectrics with the tetragonal tungsten bronze structure

, 2013
There is great interest in the development of new polar dielectric ceramics and multiferroic materials with new and improved properties. A family of tetragonal tungsten bronze (TTB) relaxors of composition Ba₆M³⁺Nb₉O₃₀ (M³⁺ = Ga³⁺, Sc³⁺ and In³⁺, and also their solid solutions) were studied in an attempt to understand their dielectric properties to ...
Rotaru, Andrei
openaire   +2 more sources

Structural, Dielectric, and Magnetic Properties of Ba2Bi9-xFe5+xTi8O39 Tetragonal Tungsten Bronze Ceramics

Materials Research Express, 2023
The formulations of Ba _2 Bi _9-x Fe _5+x Ti _8 O _39 (0 ≤ x ≤ 9) (BBFTO) tetragonal tungsten bronze structures were synthesized by the conventional solid-state method.
Sajida Shaikh, Fayaz Hussain
doaj   +1 more source

OPTICAL PROPERTIES OF AMORPHOUS THIN FILMS OF SODIUM-TUNGSTEN OXIDE BRONZES

Физико-химические аспекты изучения кластеров, наноструктур и наноматериалов, 2021
The spectral dependences were measured of the optical density of amorphous thin films of sodium-tungsten oxide bronze of the tetragonal structure and the composition Na0,3WO3, condensed on glass substrates, thermostated at temperatures of 373, 473 and ...
B.M. Khubolov
doaj   +1 more source