Sodium tungsten bronze - Wikipedia
Sodium tungsten bronze is a form of insertion compound with the formula Na x WO 3, where x is equal to or less than 1. So named because of its metallic lustre, its electrical properties range from semiconducting to metallic depending on the concentration of sodium ions present; it can also exhibit superconductivity .
钨青铜型结构 - 百度百科
钨青铜型结构tungsten bronze type structure的化合物中许多具有特殊的电性能，是重要的 电子陶瓷 材料。 化学式为： (A1)4 (A2)2B10O30和 (A1) (A2)2 (A3)4B10O30。 式中A1为 钙 、 锶 、 钡 和 铅 等；A2为 锂 、 钠 和 钾 等；A3为锂和 镁 等；B= 铌 、 钽 和 钛 等。 也可简写成A×Bl0O30。 钨青铜结构有 四方晶系 和 斜方晶系 两种，前者单元原胞都含有10个 [BO6]氧 八面体，它们沿C轴方向共角相连。 另一类为斜方晶系的钨青铜型结构可视为沿四方单胞的对角线进 …
The structure and thermoelectric properties of tungsten bronze ...
2019年9月27日 · Tungsten bronze (TB) structured materials have attracted attention as possible thermoelectrics because of their complex crystal structure. In this work, a new thermoelectric ceramic with a tetragonal tungsten bronze (TB) structure, Ba 6 Ti 2 Nb 8 O 30 (BTN), was prepared by the conventional mixed oxide route with some samples processed by Spark ...
Structural and electrical properties of tetragonal tungsten bronze ...
2024年10月1日 · Tetragonal tungsten bronzes allow for broader compositional engineering compared to perovskites. Here we investigate solid solutions between Ba 4 Na 2 Nb 10 O 30 (BNN) and K 4 Bi 2 Nb 10 O 30 (KBiN). A transition from orthorhombic to tetragonal symmetry was observed at 30–35 % KBiN.
Crystal Structure, Cation Occupation, and Phase Transitions in Ba
4 天之前 · The chemical flexibility of the tetragonal tungsten bronze (TTB) structure offers a large potential for compositional engineering. Cation size and vacancy concentration are known to affect its structure, cation disorder, and functional properties. However, the compositional complexity also makes the TTB structure challenging to understand. Here, we investigate the solid solution between ...
Structural, magnetic, and dielectric properties of tungsten bronze ...
2019年10月25日 · The structural, magnetic, dielectric and optical properties of tungsten bronze Ba 4 Nd 2 Fe 2-x Ni x Nb 8 O 30 (0 ≤ x ≤ 1) ceramics were investigated. The structural refinements indicate that all the samples exhibit the tetragonal structure with the space group of P4bm. Compared with the Ni-free sample with antiferromagnetic state, Ni-doped ...
Electronic structure of sodium tungsten bronzes
2007年4月25日 · The electronic structure of sodium tungsten bronzes, Na x W O 3, for full range of x is investigated by high-resolution angle-resolved photoemission spectroscopy (HR-ARPES). The experimentally determined valence-band structure has been compared with the results of ab initio band-structure calculation.
Structure, dielectric and magnetic properties of Ba6FeNb9O30 tungsten …
2010年10月13日 · The tetragonal tungsten bronze structure in space group P4bm is determined with the lattice parameters: a = 12.597(6) Å, b = 12.597(6) Å, c = 3.989(1) Å. An extremely high dielectric constant is indicated at higher temperatures, and it drops quickly when the sample is cooled down through a critical temperature, and this critical temperature ...
Structural and Raman properties of the tetragonal tungsten bronze ...
2010年3月1日 · Tetragonal tungsten bronze (TTB) oxides with the general formula A x B y C z Nb 5 O 15 are one of the most important classes of ferroelectrics next to perovskites. Their structure can be described as a network of slightly distorted oxygen octahedral NbO 6 linked by their corners in such a manner as to form three different types of tunnel (with ...
[PDF] The structure and thermoelectric properties of tungsten bronze ...
2019年9月27日 · Tungsten bronze (TB) structured materials have attracted attention as possible thermoelectrics because of their complex crystal structure. In this work, a new thermoelectric ceramic with a tetragonal tungsten bronze (TB) structure, Ba6Ti2Nb8O30 (BTN), was prepared by the conventional mixed oxide route with some samples processed by Spark Plasma ...