在Mica接口的稀土选择性和电潜
Michael D LaCount1, Tanya Prozorov2, Shawn M Kathmann3
1National Security Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
ACS applied materials & interfaces
|January 16, 2025
概括
在米卡中的化学替代物显著改变了当地的电潜,增强了稀土元素 (REE) 的吸附. 这种理解对于开发先进的REE分离材料至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
- 物理化学 物理化学
背景情况:
- 稀土元素 (REEs) 的选择性吸附对于高效的分离过程至关重要.
- 了解局部电位对REE吸附的影响对于材料设计至关重要.
研究的目的:
- 为了研究在米卡中的化学替代如何影响局部电潜和REE吸附.
- 为了将REE吸附能量与替代物电荷和静电电位变化相关联.
主要方法:
- 马斯科维特和花科维特的计算平均内部潜力.
- 评估了天然替代对电潜和REE吸附能量 (Ead) 的影响.
主要成果:
- 计算的潜能与实验值 (+10.6 V) 一致得很好.
- 替代剂显著改变了基底表面电位和REE吸附.
- 低电荷替代剂提高了Nd3+和Yb3+吸附能量的20-30 kcal/mol.
结论:
- 当地电潜和替代物电荷是控制REE离子吸附和米卡的选择性的关键因素.
- 电位的原子尺度变化对于优化REE分离材料很重要.
- 高分辨率电子全息/断层扫描可以提供对这些现象的见解.
相关概念视频
Trends in Lattice Energy: Ion Size and Charge
23.7K
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:
23.7K
Magnetostatic Boundary Conditions
862
An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...
862
Crystal Field Theory - Octahedral Complexes
26.1K
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...
26.1K
Ferromagnetism
2.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.4K
Metal-Semiconductor Junctions
286
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
286
Crystal Field Theory - Tetrahedral and Square Planar Complexes
41.4K
Tetrahedral 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,...
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,...
41.4K


