澄清离子电池石固态电解质中剂局部结构和对离子导电性的影响
Sundeep Vema1,2, Astrid H Berge1, Supreeth Nagendran1
1Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
Chemistry of materials : a publication of the American Chemical Society
|December 4, 2023
概括
富含的石榴石 (Li7La3Zr2O12) 中的和补充剂主要是形成副产品,不占据格子位置. 在合成过程中过量的消耗了这些剂,影响了固态电池的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 电化学 电化学 电化学
背景情况:
- 富含的石榴石 (Li7La3Zr2O12) 是固态电池的有希望的固体电解质,由于其高离子导电性和电化学稳定性.
- (Al) 和 (Ga) 兴奋剂是稳定室温Li7La3Zr2O12立方相的常见策略.
- 尽管进行了广泛的研究,但在Al和Ga化Li7La3Zr2O12中,精确的局部结构和剂位的占用程度仍然不太清楚.
研究的目的:
- 为了明确地确定Li7La3Zr2O12.3中的Al和Ga配剂的位点占用率.
- 调查观察到的NMR共振的起源及其与剂配置的关系.
- 阐明合成条件的作用,特别是过量的,在剂的行为和相位形成上.
主要方法:
- 魔术角度旋转核磁共振 (MAS NMR) 谱学用于分析局部结构和化学环境.
- 电化学阻抗光谱 (EIS) 用于测量离子导电性.
- 合成副产品的分析及其对最终材料结构的影响.
主要成果:
- 以前归因于网格位点上的兴奋剂的高频NMR共振被确定为来自γ-LiAlO2和LiGaO2副产品.
- 和两种剂都在Li7La3Zr2O12网格中的24d晶体位点上占据.
- 在合成过程中使用的过量的消耗了Al/Ga补充剂,导致这些副产品的形成和四相的稳定.
结论:
- 由过量消耗的兴奋剂形成的 γ-LiAlO2 和 LiGaO2 副产品的存在,显著影响了 Li7La3Zr2O12 网格中的实际兴奋剂度.
- 这些副产品即使在烧结后仍然存在,并影响固体电解质的离子导电性.
- 精确控制合成条件至关重要,以最大限度地减少副作用的形成,并优化Li7La3Zr2O12固体电解质的性能.
更多相关视频
相关概念视频
02:58Crystal Field Theory - Octahedral Complexes
26.6K
Crystal Field Theory
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...
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...
26.6K
02:54Trends in Lattice Energy: Ion Size and Charge
23.9K
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:
23.9K
02:42Ionic Crystal Structures
14.4K
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...
14.4K
01:19Ionic 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
02:42Valence Bond Theory
8.6K
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...
8.6K
02:51Metal-Ligand Bonds
20.8K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
20.8K