関連する実験動画
Updated: Jun 28, 2026

06:44
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
格子ダイナミクスは,固体酸化イオン導体における低温酸素の移動性を誘発する
Werner Paulus1, Helmut Schober, Stefan Eibl
1Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes1, Inorganic Materials: Soft Chemistry and Reactivity of Solids, Campus de Beaulieu, F-35042 Rennes, France. werner.paulus@univ-rennes1.fr
Journal of the American Chemical Society
|November 7, 2008
まとめ
ストロンチウム鉄酸化物 (SrFeO ((2.5)) は,鉄酸化カルシウム (CaFeO ((2.5)) と異なり,格子ダイナミクスにより,低温の酸素流動性が顕著である. この発見は,高度な酸素イオン導管の設計に新たな道を開く.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- 無機化学 無機化学とは
背景:
- ストロンチウム鉄酸化物 (SrFeO ((2.5)) とストロンチウムコバルト酸化物 (SrCoO ((2.5)) は,室温で反転的に酸素を間接し,立方ペロフスキットを形成します.
- 鉄酸化カルシウム (CaFeO ((2.5)) は,酸化のために極端な条件を必要とし,酸素の移動性における重要な違いを強調します.
研究 の 目的:
- カフェオ (CaFeO) と比較して,SrFeO ((2.5) の低温酸素の移動性が顕著である理由を解明する.
- 酸素不足のペロブスキートにおける酸素拡散を促進する格子ダイナミクスの役割を調査する.
主な方法:
- 温度に依存する酸素同位体交換実験で, (18) O/(16) O. を使った.
- 不弾性中性子散射 (INS) 研究. 不弾性中性子散射の研究.
- アブ・イニシオ (密度関数理論) 分子動的計算.
主要な成果:
- 600K以下の SrFeO (x) において,自由酸素の移動性が確認されました.
- 低温の酸素の移動性は,特定の低エネルギー格子モードと関連しています.
- SrFeO (((3-x) のフォノン・アシストされた強化された酸素拡散は,頂点酸素原子の弱まったFe-O-Fe結合に起因する.
結論:
- 格子ダイナミクスは,酸素不足のペロブスキット,特にブラウンミレライト構造を持つペロブスキットにおける酸素の移動性に大きく影響します.
- フォノン補助拡散のようなダイナミックに誘発された現象は,オキシドイオン移動を容易に可能にします.
- これらの発見は,低温酸素イオン導管の設計と調整のための新しい概念を提供します.
関連する概念動画
Trends in Lattice Energy: Ion Size and Charge
An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure of the strength of this attraction. The lattice energy (ΔHlattice) of an ionic compound is defined as the energy required to separate one mole of the solid into its component gaseous ions. For the ionic solid sodium chloride, the lattice energy is the enthalpy change of the process:
Lattice Energies of Ionic Crystals
Lattice energy represents the energy released when gaseous cations and anions combine to form an ionic solid, reflecting the strength of electrostatic interactions within the crystal. This process is fundamentally governed by Coulombic attraction between oppositely charged ions, where the potential energy varies inversely with the interionic distance and directly with the product of ionic charges. As ions approach one another, the electrostatic energy becomes increasingly negative, indicating a...
Molecular and Ionic Solids
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
The Born-Haber Cycle
Lattice Energy
Theory of Metallic Conduction
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...

