在MgCr2O4中进行非传统的电荷传输以及对电池间隔主机的影响
Ian D Johnson1,2, Aashutosh N Mistry1,2, Liang Yin2,3
1Chemical Sciences & Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
在MgCr2O4阴极中离子的传输受到导电性的限制,而不是扩散性. 一个扩展的理论解释了这些相互作用,对于设计先进的多价离子电池至关重要.
科学领域:
- 材料科学
- 电化学
- 固态离子
背景情况:
- 固态阴极中的离子传输限制了电池的充/放电速度.
- 离子电池具有高能量密度的潜力,但在阴极材料性能方面面临挑战.
- MgCr2O4是一个有前途的阴极材料,但它的电化学行为显示了传统的离子传输理论无法解释的局限性.
研究的目的:
- 研究MgCr2O4的远程离子传输机制.
- 开发和验证一种扩展的离子运输理论,该理论解释了物种间相互作用和非理想的自由能量.
- 将MgCr2O4与离子材料的离子传输特性进行比较.
主要方法:
- 密集的MgCr2O4颗粒的电极化.
- MgCr2O4的电化学表征
- 一个扩展的纳斯特-爱因斯坦理论的发展,包括摩擦相互作用.
主要成果:
- 在MgCr2O4中,Mg的化学扩散性与离子电极材料中的扩散性相当.
- 发现MgCr2O4的总离子导电率是电池性能的限制因素.
- 提出的扩展理论准确地描述了观察到的离子运输行为,与传统模型不同.
结论:
- 不同于离子系统,MgCr2O4中的能量储存受到粒子尺度电压下降的限制.
- 在多价离子系统中,物种间相互作用显著影响连续运输特性.
- 未来的阴极材料设计应纳入离子电池和其他多价离子电池性能改善的扩展理论的原则.
更多相关视频
10:03Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
相关概念视频
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Ionic Bonding and Electron Transfer
Ionic Crystal Structures
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...
Ions and Ionic Charges
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Trends in Lattice Energy: Ion Size and Charge
