在稳定的delta-Bi2O3中增强了氧离子导电性
Rita Punn1, Antonio M Feteira, Derek C Sinclair
1School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, UK.
Journal of the American Chemical Society
|November 30, 2006
概括
新的替代 bismuth 氧化物 (Bi2O3) 材料与兰化物离子具有高氧化物离子导电性. 这些新的delta-Bi2O3相为先进的电化学应用提供了潜力.
科学领域:
- 固态化学 固态化学
- 材料科学是一种材料科学.
- 电化学 电化学 电化学
背景情况:
- 氧化物 (Bi2O3) 以其在固体氧化物燃料电池中的潜力而闻名.
- 在较低温度下稳定高导电性三角形-Bi2O3相仍然是一个挑战.
研究的目的:
- 为了研究三角形-Bi2O3结构的稳定.
- 为了探索新型替代相的氧化离子导电性.
主要方法:
- 用和替代的固态合成Bi2O3.3.
- 使用X射线衍射进行结构性表征.
- 电化学阻抗光谱法用于测量离子导电.
主要成果:
- 成功合成了具有Bi12.5La1.5ReO24.5.5等组成的新型delta-Bi2O3相.
- 观察到异常高的氧化离子导电率 (约. 10-3 S cm-1 在300°C).
- 在间歇性离子位点中发现了与理想化物位置的显著结构偏差.
结论:
- 和兰坦化的共同替代有效地稳定了三角洲-Bi2O3阶段.
- 这些新材料在降低工作温度下显示出有前途的离子导电性.
- 独特的结构特征与增强的离子运输特性有关.
相关概念视频
Colors and Magnetism
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
Diamagnetic Shielding of Nuclei: Local Diamagnetic Current
An applied magnetic field causes the electrons present in the molecule to circulate, setting up a local diamagnetic current within the molecule. The local diamagnetic current arising from circulating sigma-bonding electrons induces a magnetic field, Blocal that opposes the applied magnetic field, B0. The effective magnetic field experienced by these nuclei is given by the difference between the applied and local magnetic fields in a phenomenon called local diamagnetic shielding. Essentially,...
Ionic Strength: Effects on Chemical Equilibria
The addition of an inert ionic compound increases the solubility of a sparingly soluble salt. For example, adding potassium nitrate to a saturated solution of calcium sulfate significantly enhances the solubility of calcium sulfate. Le Châtelier's principle cannot predict this shift in the equilibrium. Instead, this could be explained in terms of changes in the effective concentration of the ions in solution in the presence of added inert salt.
In this solution, the primary cation—the calcium...
In this solution, the primary cation—the calcium...
The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...


