石盐氧化物的结构设计原理,用于过剩的阴极材料
Qinwen Cui1,2, Yi Li1,2, Yining Li1,2
1State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050, China.
ACS nano
|January 11, 2024
概括
研究人员开发了一种描述器来设计过量氧化物阴极. 这导致了一种具有高容量,良好的循环稳定性和速率能力的新Li过量阴极材料.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 固态化学 固态化学
背景情况:
- 过量的氧化物阴极通过阴离子和阳离子氧化还原提供高容量.
- 层状和离子失序的过量氧化物具有像容量衰变和不稳定性等局限性.
研究的目的:
- 通过组合分层和无序相来设计具有多余阴极材料,以提高性能.
- 开发一种用于控制氧化物过剩中的晶体结构的预测描述器.
主要方法:
- 关联离子半径和电子配置来预测晶体结构.
- 过剩氧化物阴极材料的实验合成.
- 电化学性能,循环稳定性和速率能力的表征.
主要成果:
- 一个描述符成功地预测了分层,无序和共存的结构.
- 合成的Li1.2Ni0.4Mn0.2Nb0.2O2呈现出一个纳米级层层层的无序共存结构.
- 实现高特异性容量 (312 mAh g-1) 具有出色的循环稳定性和速率能力.
结论:
- 开发的描述器使过量阴极材料的合理设计成为可能.
- 同时存在的纳米结构战略有效地结合了不同阶段的优势.
- 这种方法为开发先进的多余阴极材料提供了宝贵的途径.
相关概念视频
Ionic Bonding and Electron Transfer
41.6K
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
41.6K
Ionic Crystal Structures
14.3K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
14.3K
Voltaic/Galvanic Cells
57.3K
Spontaneous Chemical Reactions
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
57.3K
Electrolysis
26.4K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
26.4K
Formation of Complex Ions
23.6K
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...
23.6K
Ionic Strength: Effects on Chemical Equilibria
1.5K
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...
In this solution, the primary...
1.5K


