原子到纳米尺度障碍的协同效益:混合层-脊柱高透氧化物阴极材料的电化学和结构演变
Jessica Luo1,2, Cynthia Huang2,3, Zachary R Mansley4
1Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, United States.
ACS applied materials & interfaces
|December 23, 2025
概括
离子电池中的高氧化物 (HEO) 显示出改善性能的希望. 这项研究表明,稳定的HEO结构 (HEO-H) 通过在循环过程中保持结构完整性来减轻电压衰减,与HEO-L不同.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 高氧化物 (HEO) 为能源应用提供了先进的材料特性.
- 富含和的氧化物中的电压衰减限制了它们在离子电池中的使用.
- 在复杂的高等教育机构中理解结构-功能关系是具有挑战性的.
研究的目的:
- 调查两个具有不同含量 (HEO-L和HEO-H) 的HEO中的结构和化学变化.
- 为了将原子级高设计和纳米级相组合与电化学性能相关联.
- 阐明和丰富的高电极材料中电压衰减背后的机制.
主要方法:
- 两个高氧化物的合成和表征:HEO-L (Li1.5Mn0.6Ni0.1Co0.1Fe0.1Al0.1Oy) 和HEO-H (Li0.5Mn0.6Ni0.1Co0.1Fe0.1Al0.1Oy).
- 用X射线衍射 (XRD) 和电子显微镜进行晶格和微观结构分析.
- 用光谱技术探测化学状态并识别氧气空缺和金属离子减少.
主要成果:
- HEO-L 显示出更高的初始容量,但由于相位转换 (分层到螺旋状),氧气损失和金属减少而降解,导致电压衰减.
- 在100个循环后,HEO-H在最小容量和电压衰减的情况下保持了其分层旋转螺旋混合结构.
- 由于其稳定的结构和可逆的相位过渡,HEO-H的氧气损失和金属离子减少有限.
结论:
- HEO-H的结构稳定性可以防止显著的氧气损失和金属离子减少,从而抑制电压衰减.
- 在HEO-H中的高设计促进可逆相变,这对于离子电池中稳定的电化学循环至关重要.
- 定制HEO的组成和结构是克服电压衰减和增强先进阴极材料的实际应用的关键.
相关概念视频
Valence Bond Theory
8.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
8.9K
Colors and Magnetism
12.1K
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...
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...
12.1K
Electron Configurations
20.3K
Electron configurations and orbital diagrams can be determined by applying the Aufbau principle (each added electron occupies the subshell of lowest energy available), Pauli exclusion principle (no two electrons can have the same set of four quantum numbers), and Hund’s rule of maximum multiplicity (whenever possible, electrons retain unpaired spins in degenerate orbitals).
The relative energies of the subshells determine the order in which atomic orbitals are filled (1s, 2s, 2p, 3s, 3p,...
The relative energies of the subshells determine the order in which atomic orbitals are filled (1s, 2s, 2p, 3s, 3p,...
20.3K
Atomic Nuclei: Nuclear Spin State Overview
1.9K
NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...
1.9K
Atomic Nuclei: Nuclear Relaxation Processes
1.1K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
1.1K


