ナイオン電池のナサイトマグニウム置換によるP2構造のカソッド材料の調節
Qin-Chao Wang1, Jing-Ke Meng1, Xin-Yang Yue1
1Department of Materials Science , Fudan University , Shanghai , 200433 , People's Republic of China.
Journal of the American Chemical Society
|December 19, 2018
まとめ
マグネシウム (Mg) イオンは,ピラーとして作用し,充電順序を乱すことで,ナトリウムイオン電池のP2型層状酸化カソッドを安定させます. これは構造的安定性を高め,可逆性酸素還酸化を促進し,より滑らかな電圧プロファイルと性能を改善します.
科学分野:
- 材料科学
- 電気化学
- 無機化学
背景:
- P2型層酸化物は,通常,ナトリウムイオン電池で複数の電圧高位を示します.
- これは,Na-Naの静電相互作用と移行金属の電荷配列から生じるNa+/空位配列の上部構造に起因する.
- これらの問題は,これらの正極材料の電気化学性能と安定性を制限します.
研究 の 目的:
- 改善された電気化学性能を持つナトリウムイオン電池のための新しいP2タイプの層状酸化物カトド材料を設計する.
- Na0.7[Mn0.6Ni0.4]O2の構造と電気化学的性質に対するMgイオンドーピングの影響を調査する.
- リバーシブルな酸素リドックスを促進し,スムーズな電圧プロファイルを達成します.
主な方法:
- MgドーピングされたP2型層酸化物の合成:Na0.7Mg0.05[Mn0.6Ni0.2Mg0.15]O2.
- X線微分法 (XRD) およびその他の技術を用いた構造的特徴化.
- サイクル安定性,速度能力,および電圧プロファイルを含む電気化学性能評価.
主要な成果:
- Naと移行金属の両方に導入されたMgイオンは,層構造を安定させ",柱"として作用し,電荷の順序を乱します.
- Mgドーピングは"Na-O-Mg"と"Mg-O-Mg"の構成を生み出し,イオン的O2p特性と可逆酸素還元性を促進する.
- Mgドーピングされた材料 (Na0.7Mg0.05[Mn0.6Ni0.2Mg0.15]O2) は,スムーズな電圧プロファイル,高い構造的安定性,高い速度および高いカットオフ電圧 (4.2V) で優れた容量保持を示しています.
- 充電後に新しいP2相が形成され,代替材料のO2相とは異なり,
結論:
- Mgドーピングは,ナトリウムイオン電池のP2型層酸化物の限界を克服するための効果的な戦略です.
- 強化された電気化学的性能は,構造的安定化と促進された酸素還元活性に起因する.
- この研究は,高性能ナトリウムイオン電池のための高度な層状カトド材料の設計に新しい道を開きます.
関連する概念動画
Batteries and Fuel Cells
30.9K
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
30.9K
Lewis Structures of Molecular Compounds and Polyatomic Ions
45.2K
To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:
45.2K
Common Ion Effect
46.6K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
46.6K
Formation of Complex Ions
26.1K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
26.1K
DC Battery
1.3K
A conductor needs to be a component of a path that creates a closed loop or full circuit to have a continuous current flowing through it. A current starts to flow if an electric field is created inside an isolated conductor that is not part of a full circuit. The conductor quickly develops a net positive charge at one end and a net negative charge at the other. These charges generate an electric field opposite the direction of the applied electric field, which reduces the current. Eventually,...
1.3K
Precipitation of Ions
30.3K
Predicting Precipitation
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
30.3K


